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About Google Book Search Google's mission is to organize the world's information and to make it universally accessible and useful. Google Book Search helps readers discover the world's books while helping authors and publishers reach new audiences. You can search through the full text of this book on the web at |http : //books . google . com/ MILITARY '-* ^' • . > OBSERWION Lm^ ^m^- • # ^ D.Van Nostrand Company 1 Digitized by Googl ■hWT' Digitized by Google \ \ Digitized by Google Digitized by Googk Digitized by Google Digitized by Google MILITARY OBSERVATION BALLOONS (CAPTIVE AND FREE) A COMPLETE TREATISE ON THEIR MANUFACTURE, EQUIP- MENT, INSPECTION, AND HANDLING, WITH SPECIAL INSTRUCTIONS FOR THE TRAINING OF A FIELD BALLOON COMPANY By EMIL J. WIDMER 3 FLATB8 AND 38 JLLUSTSATIOXS NEW YORK D. VAN NOSTRAND COMPANY 25 Park Place 1917 Digitized by Google Copyright, 1917, by D. VAN NOSTRAND COMPANY Digitized by Google PUBLISHER'S NOTE The value and importance of a volume covering the field of mSitaiy balloons becomes obvious since keen students of the present world war have declared that the struggle will be won in the air. This book on the man- ufacture, equipment, inspection and handling of military observation balloons gives a complete survey of the field. It is based on the Balloon Manual of the German Army, including drill and equipment in use at the beginning of the war. 371697 Digitized by VjOOQIC Digitized by Google CONTENTS CHAPTIt PAOB I. Description of a Kite BaDoon i n. Equipment of a Kite Balloon i6 m. The Crew of a Kite Balloon, Officers and Men. The Infla- tion. Selection of the Anchoring Site. Preparation for Ascension. The Ascension 28 IV. Training of the Field Balloon G>mpany 44 ^ V. Inflating and Handling of a Kite Balloon during Maneu- vers. Duties of the Balloon Squad. Duties of the Car Squad; of the Rope Squad. Balloon Transport, with Ascension Ropes; Transportation Ropes. Aid of Crew. High Transportation. Marching Order of the Balloon Transportation. Lifting over Obstacles. De- flation and Refilling of the Balloon 65 _ VI. The Use of a Kite Balloon in Time of War 80 VIL The Rules for Examining and Accepting the Goth to be Used in the Manufature of a Kite Balloon. The Care of Material and Its Repair 94 Vin. Materials Used 103 ' IX. The Spherical Captive Balloon. Equipment; Inflation; Anchoring; Ascension 125 X. The Free Balloon. Equipment. Preparation for Ascen- sion. The Ascenaon. 145 VU Digitized by Google Digitized by Google MILITARY OBSERVATION BALLOONS CHAPTER I Description of a Kite Balloon The kite balloon is a cylindrical gas bag with hemispheri- cal ends, that sets itself, diagonally, like a kite, to the direc- tion of the wind. The shape is maintained by the use of an air bag, or ballonet, which is situated inside the balloon proper, and at the rear or lower end. By means of an ingeniously arranged inlet and valve, air is automatically forced under pressiure into the ballonet by the wind. Suppose the balloon to be inclined to the horizontal at an angle of from 30® to 40®, and that a horizontal plane is taken which passes through the center point around which the hemispherical end is formed. The ballonet is now made by extending an inner skin down around the lower end of the bag, below the edges of this horizontal plane. It is seciu^ly sewed and cemented to the body of the balloon along its edges. It is therefore joined to both the cylin- drical and hemispherical portions, forming a sort of an inner envelope, leaving, however, a space between the two into which the air can be driven by the wind. When the balloon is fully inflated, the inner envelope extends down- Digitized by Google 2 MIUTARt OBSERVATION BALLOONS waid and at its smallest possible distance from the outer envdope. As soon as the ballocm rises the gas eipands^ and the pressuie on the envelope would increase to the bursting point if the gas were not allowed to escape. A valvei however, which is situated at the upper end of the ballo(m, is automatically opened by means of a chain, which extends from this valve to the center point on the innar envelope of the ballonet. This chain becomes taut and pulls the valve open when the airbag becomes empty. The careful adjustment of this chain is, therefore, a matter of great importance. As soon as the balloon begins to contract, air enters through the opening to the air bag, and the valves closes of its own accord. In the ballonet a non-return valve prevents the air from escaping. The air is slightly compressed by the action of the gusts of wind, and this pressure extends to the gas and reacts upon the envelope. This is resisted by an internal pressure equal to that on the outside, and also by the static pressure acting on the top of the balloon. If there is a sufficiency of gas the envelope will always retain its shape. As soon as the gas expands and the pressure in- creases, the air is forced out of the air bag through a third non-return valve. This valve opens into an outside air bag, or steering bag, as it will be termed hereinafter. The wind therefore automatically supplies any deficiency which may arise. As mentioned above, the balloon assumes an inclined position of about 30^ or 40° to the horizontal. This position is affected through the method by which the cable is attached. It is held captive not by a rope connecting Digitized by Google DESCRIPTION 8 to the basket, as in the case of cylindrical or pear-shaped balloons, but by a series of branch ropes which extend from the main cable to a girdle nmning around the body of the balloon, on a line parallel to and at a short distance below its longar axis. By this method of attachment the pull of the cable is distributed along the balloon and prevents any tendency to bend or buckle. As it is important that the longer axis of the balloon should be kept pointing in the direction of the wind, a steering bag or rudder is provided. This is attached to the Iowa: end of the gas bag and extends about half way around the hemispherical end and for several feet along the bottom of the cylindrical portion. The wind enters the steering bag throu^ a non-return valve at its forward end and escapes through another valve at the back toward the top. These valves are so adjusted that there is alwajrs a slight excess of pressure in the steering bag over that of the outside atmosphere, but it must always be less than that in the ballonet itself, which discharges into it The steering bag, having a slight excess of pressure in it, is kept extended and its effect on the entire t)alloon is similar to that of the large end of a weather vane, which always keeps the smaU end pointing into the wind. In orda: that these movements should not take place too suddenly, a tail is fastened on behind, and is secured to the main body of the balloon by branch ropes which extend to either side and fasten to a girdle. This tail consists of a long rope to which wind-catchers are fastened at certain intai^; these tail cups somewhat resemble inverted umbrellas. The wind, catching in these, tends to check any movement of the balloon, and a part of the kite effect Digitized by Google 4 MILITARY OBSERVATION BALLOONS is lost. To neutralize this disadvantagei two saib are placed one on either side and toward the rear end of the balloon. In addition to offsetting the dragging-down effect of the tail, these sails increase the stability. The basket is fastened to the girdle of the balloon by a separate siiq>ension from that of the holding cable. A telephone connection is made with the gromid by means of a wire which runs up inside of the main cable and, coming out of the upper end, runs in a long loop to the basket. A valve-control rope extends from the basket up to the gas valve, so that in case a quick descent is desired the operator may allow the gas to escape by giving a strong tug on this rope. This valve, therefore, has two controls, one of which extends to and is fastened to the ballonet as previously described, and which opens the valve automatic- ally, and one which nms to the basket, enabling the pilot to open the valve quickly. A further means for a quick descent is provided by the use of a ripping panel This is nothing less than a patch on the gas bag which, by a strong pull on the rope running to the basket, can be ripped off, thus leaving a hole through which the gas rapidly escapes. Experience shows that a captive balloon of the kite type maintains its position in the air with very little oscil- lation and that accurate observations are possible, and that maximum comfort is afforded to the observer. Detailed Description The kite consists of the envelope, rigging and the car. Envelope. The envelope, which is cylindrical in shape and has hemispherical ends (Plate I), is made of yellow Digitized by Google . — Kite Balloon. (To face page 4) Google Digitized by Digitized by Google Digitized by Google Digitized by Google DESCRIPTION 6 rubberized diagonal cloth, and is put togethar by means of gores and segments. It consists of the gas bag G (Figs. 3 and 4), the ballonet B (Figs. 3 and 4), and the steering ballonet S (Plate I, Figs. 3 and 4). Gas Bag. The gas bag constitutes the greater part of the envelope and contains the gas for lifting the balloon. It is cylindrical in shape; the front end is bordered by the OcenoN*. hemispherical nose and the rear by the ballonet wall which is sewed to the gas bag along Bw (Figs. 3 and 4). Valve. The valve is set in the nose of the balloon. This valve serves for the escape of the gas and regulates the pressure; it is set to work either automatically or by a rope control from the car. It consists of the wooden valve body B (Fig. i), th^ aluminum disk D, together with the valve cord VI (Plate I, Figs, i, 3 and 4), the valve chain Vc (Figs. I, 3 and 4), and the springs 5, with the elbow Digitized by Google 6 MILITARY OBSERVATION BALLOONS (Figs. I and 2), the butterfly screws F, with the washer and the two rubber packing rings. ^ The leather valve cup Vk (Fig. i) serves as a protector to the valve and is to be taken off only when the balloon ascends. Digitized by Google DESCRIPTION Digitized by Google 8 MILITARY OBSERVATION BALLOONS Operating the Valve. By drawing in on the valve disk the valve opens and causes the spring to expand. Valve Chain. The valve chain Vc (Figs, i, 3 and 4) is made of steel, covered with light-weight cloth. It runs from the valve and, branching off near its rear end, connects the ballonet wall at three different points. When the gas bag is completely inflated it e:q>ands and the valve is opened automatically. Valve Rope. The valve rope VI (Plate I, Figs, i, 3 and 4) is of a yellow color and runs from the disk through an opening in the balloon. To prevent gas from leaking out around this rope at the balloon wall, a conical re- versing bag Bh (Figs. 3 and 4) is provided. In order to prevent the opening of the valve by accident the rope is formed in a loop immediately outside of the conical re- versing bag, and is fastened to the gas bag at point a (Figs. 3 and 4) . This loop must be opened only when it is absolutely necessary. By giving a strong pull on the rope, from the car, the fastening at point a (Figs. 3 and 4) is torn off and the valve can then be pulled open. Appendix. The appendix / (Plate I, Figs. 3 and 4) is in the shape of a cylindrical bag and is attached to the cyKn- drical part of the gas bag. It serves as a lead for the in- flating tube into the balloon. After the balloon is inflated the lower end of the appendix is folded upward, and the whole is securely and tightly woimd with a soft cord in order to prevent the gas from escaping. Ballonet and Ballonet Wall. The ballonet wall sepa- rates the gas bag from the ballonet and is made of the same material as the envelope. It is sewed to the cyHn- drical and the rear hemispherical part of the balloon along Digitized by Google DESCRIPTION Digitized by Google 10 MILITARY OBSERVATION BALLOONS the seam Bs (Figs. 3 and 4). When the balloon is entirely inflated the ballonet wall stands 4 inches away from the hemi^herical end at the rear of the envelope. a. The ballonet B (Hgs. 3 and 4) is situated in the back lower part of the envelope and serves the purpose of holding the shape of the balloon in case the gas bag is not completely inflated and in the event of a wind. It is connected with the outside air by means of an air inlet Si (Plate I, Figs. 3 and 4). b. This air inlet, the q)ening of which is funnel-shaped, has a flap valve in the inside made of doth which allows the air to enter into the ballonet space. It also keeps the air from escaping through this opening. c. When the gas bag is fully inflated the balloon is extended to its true shape. In order to retain this shape when there is an insufficiency of gas, the air which has been forced into the ballonet by the wind pushes the ballonet wall upward until the gas is under the same pressure as the air itself. d. When the gas expands, in order that the pressure may not become too great on the envelope, a non-return valve Bv (Figs. 3 and 4), which is adjusted by an elastic band instead of springs, allows the air to escape from the ballonet into the steering bag. Steering Bag. The steering bag S (Plate I, Figs. 3 and 4) is fastened to the rear end of the balloon and serves the purpose of holding it, by means of its steering effect, in the direction of the wind. a. The steering bag is made of standard balloon doth and is sewed on to iht lower part of the gas bag. It is further hdd in place by means of rigging, which Digitized by Google DESCRIPTION 11 f Jf^ V ' ID \ "^ ■^ yfi ; hone with a ground conductor. This is obtained by means of a non-insulated wire, running from the iron binding screw to the conductor stuck in the earth (a sword or bayonet), and in that way connects the free line terminal of the telq>hone with the ground. When the last method of connection (of the second station) is to be considered, the cable drum and the non- insulated binding screw offer a better circuit when the ground is damp. Optical Signals. The equipment of visible signals by day consists of a red and a white hand-signaling flag; at night an electrical signah'ng apparatus is used. Electrical Signaling Apparatus. The electrical signal- ing apparatus consists of a battery case, an electric lamp, and the circuit cables. The battery furnishes the current for the lamp. It consists of a hard-rubber case with a cover, which is divided into six cells and placed in a small wooden box. Six pairs of electrodes are fastened onto the cover in conformity with the cells of the rubber case. The positive electrode of every element consists of two carbon plates, which are separated by a small space. The n^ative electrode of every element consists of a Digitized by Google EQUIPMENT 27 tough zinc plate covered with linen, which fills in the space between the carbon plates. The carbon electrodes of a cell are connected with the zinc electrode of the next element by means of a brass piece and two binding screws. By this arrangement we have a free positive and negative electrode, and make there- by the battery poles which are connected with the circuit cable of the lamp by means of its binding screws and wire. The fluid for charging a battery consists of a composition of one part double strength chromate of potassium, three parts water and one part muriatic add. The cells are to be filled a little over half full, and after the electrodes have been installed the battery is in working order. The connecting wires of the lamp are fastened in the free terminal of the battery. To light the lamp a button is pressed with the resultant flow of current. In operating the signaling apparatus, it is essential that the various screws and plates be kept clean and held fiimly in place. Also the linen covers of die zinc plates must not be torn or injured in any way, as they supply the necessary insulation for zinc and carbon. When the zinc plates have become much worn through long service they i^ould be replaced by new ones covered with iM:epared linen. The lamp will bum eight hours from a battery charge of 33 quarts of solution. Digitized by Google CHAPTER m The Crew of a Kite BaUoon, Officers and Men. The Inflatioii. Selection of the Anchoring Site. Preptnttion for Ascension. The Ascension* Assigning of Officers and Men. The commander of the balloon squad assigns the officers according to his own judgment. The balloon observer is stationed in the car and reports the outlook. The pilot with the car squad supervises the installation and working of the telephone and the other apparatus. He must assbt the observer. The officer in chai::ge directs the work of the balloon; that is, he sees to the couplings, the ascension, tranqx)rt- ing, anchorage, etc. The commander of the ground station supervises the laying out and anchoring of the mooring cable and the establishment of the ground station and is responsible for the maintenance of service. The commander of the next station lays the conductor and supervises it. A petty officer may be made commander of this station. The officers in reserve can be appointed for service at the groimd station or for mapping out the next station. The Crew. There are at least forty-eight men required for a kite balloon. They are divided into eight squads 28 Digitized by Google OPERATION 29 which consist of five men and one leader each. K there are more then forty-eight men the rest form a reserve group. The squads i to 6 are detailed for the balloon, squad 7 for the car, and squad 8 for the ropes. The men in a squad are numbered i to 6, the leader being No. i. The balloon squads are used for the balloon only. Those who have the imeven numbers are placed on the left side and those having the even numbers are on the right. To determine the left or right side of a balloon one looks from the car toward the safety valve. The duties of the car squad are the equipment of the car, its fastening, the fastening of the mooring cable to the balloon, and the connection of the telephone station in the car. The rope squad must lay out the mooring cable and fasten it and establish a ground station. The reserves help to lay out the mooring rope, and in case it is necessary, assist in constructing the telephone circuit to the second station and do guard duty when transporting the balloon, and are called upon to help out whenever necessary. Inflation of a Ejcte Balloon Examination. An officer must examine every balloon and when he has pronounced the envelope to be faultless and decided that the rigging and valve are in perfect order, the balloon is inflated. Inflating Gas. A kite balloon is usually inflated with hydrogen. Any balloon which has a capacity of over 35,000 cubic feet can also be inflated with illuminating gas. Place of Inflation. The inflating of a balloon should Digitized by Google 30 MILH^ARY OBSERVATION BALLOONS be done out of sight and beyond the gun range of the enemy, and in a place shielded from the wind. The car group must dear the space of all pointed stones, glass and other objects which might puncture the balloon and then lay the blanket upon that clearing. The carrying and spreading out of the balloon must be done by the balloon squad, during which time the rope squad must fill the sand bags. Gas Squad. The men with the exception of those classed as tradesmen are divided into groups of fourteen to sixteen men each. The division of o&cers and the re- lieving men are regulated. Preparation. Tlie balloon is placed upon the rectangu- lar blanket with the valve in the direction of the wind, and is q)read out so that the belt is on the drcmnference and that the cloth of the envelope is smooth. As the belt runs under the equator it is necessary to make several vertical folds in the upper material. The sand bags are to be evenly distributed aroimd the balloon and are to be attached to the ropes on the belt. The valve chain is so placed that it lies perfectly straight and the valve rope lies free. The valve must be examined; then the tin pipe is placed in the appendix and is tied on (gas tight), by means of a soft cord; the other end is connected in like manner with the filling hose of the gas apparatus when the gas is let in. Completed Inflation. The inflation is completed when the valve opens automatically. After the inflation is completed the tin pipe is removed from the appendix and the latter is securely tied up so as to be gas tight. It must be equipped with a safety cap. Digitized by Google OPERATION 31 The Selection of the Anchoring Site Site. The anchoring place should be out of the range of the firing of the enemy and also out of their sight, and shielded from the wind. The best places are roomy hol- lows, quarries, unused highways, and behind houses and groups of trees. On a flat, improtected plain, wagons can be placed on the windward side to give the neces- sary protection from the wind. Afterward, the earth is thrown up by trenching on that side in the direction of the wind. This embankment is fonned in the shape of the balloon. The use of improvised balloon sheds and wooden walls on the windward side is of advantage. The preparation of an anchoring place is the same as that of an inflation place. The balloon is to be anchored on the blanket in an imcoupled condition, fastened and weighed down by sand bags. Balloon Watch. A balloon watch must always be ready at the anchoring place, and have mallets, stakes, and ropes at hand. Under normal weather conditions and when the bal- loon is anchored near its storing place, the watch should con- sist of at least one commander and three men, and they must serve as a day and night guard. In unpleasant weather and when the balloon is far away from its storing place the number of men is increased according to the judgment of the commander of the balloon squad and an officer must stay with the balloon at all such times. The watch commander should see that the following pomts are covered: Digitized by Google 32 MILITARY OBSERVATION BALLOONS Under rising temperature and corresponding gas ex- pansion the holding lines must be slackened. Under falling temperature the same lines must be tightened. It is best to dry the rope first in case it has become wet In anchoring during an increasing wind, the anchorage is to be strengthened accordingly. Should the wind become 80 severe as to threaten to tear the balloon from the moor- ings, the officer at the balloon must as a last resort order the balloon to be cut open. • • • 35 — f y • f t ± Fig. 14.— Layout for Mooring. This work is done by those men who are not at a given post, or the relief squad can be called upon to do it. Salutes are not given during the work, but after its completion. Anchoring. The anchoring of a kite balloon is divided as follows: 1. The laying out of the mooring place is done by the reserve squad by means of two mallets and twenty stakes (Kg. 14). 2. Stretching the rectangular blanket with its long side toward the direction of the wind, or in a direction best suited for the conditions of the place. Digitized by Google OPERATION 33 3. Transporting the balloon with the valve in the direc- tion of the wind onto the blanket, throwing over the anchor- ing bands (by means of the pliumnet) by the car groups. 4. Fastening the anchor bands to the stakes, placing the valve cap on the valve, arranging the tackling and weighing down the balloon with sand bags, by the car squad and lead- ers (No. i) of the balloon squad. 5. Arranging the mooring rope by the rope squad, the car by the car squad, the equipment of the car by the reserve squad (car squad). Preparation for the Ascension of a Kite Balloon Preparation of Equipment. During the inflation of the balloon, before the division of the men, the officer, together with those leaders No. i of the car and rope squads, must see that a hand wagon or a rack wagon is loaded in the following manner: The car squad must see that it has, for the equipment of the car, a cross rope with a running pulley, tow rope, 8 tail cups, I roll of the traction rope, i rope pulley, 2 red and 2 white hand flag signals. The rope squad must have i complete mooring rope, 3 rope clamps, 3 tree ropes, 2 rope pulleys, i completely packed telephone-box equipment, 3 receivers for micro- phone telephone case, 4 drvans vnth 3300 feet telephone wire, 3 conductors, i telephone wire dnun frame. If the place of ascension is distant or in case a rack wagon or a farm wagon must be packed, the blanket, the anchoring material (20 stakes, 50 sand bags, 3 anchor bands, 4 mallets), — ^in fact a complete set of tools and a hand wagon — ^must be taken along. Digitized by Google 34 lOUTARY OBSERVATION BALLOONS Activity. The preparation for ascension of an anchored kite balloon consists of: 1. The lifting of the moorings. 2. Transporting the car to the place of ascension; equipment of the car station. 3. Laying out the cable clamp of the mooring cable and equipment of the telephone station. 4. Transporting the balloon to the place of ascension. 5. The coupling together. Arrangement of the Crew. Upon the command of '^ Report for Service '' all men step in front of the balloon in the manner shown in Fig. 15. The oldest petty officer fills in the missing numbers with men taken from the reserve squads and gives the report. The officers are assembled with the coimnanders of the various squads. In order to divide the men, the command " To the balloon " is given, whereupon the squads take their places as shown in Fig. 15 and the men seize the rigging ropes. Balloon Squad. When the balloon is to be transported for a considerable distance, the officer orders the men of squad No. i and squad No. 2 to fasten five sand bags along each side of the balloon. These bags are distributed at equal distances along the long sides, and remain so fastened until the site of ascension is reached. Upon com- niiand of the officer the same men remove the bags. Car and Rope Squad. The command for the forward march of the cai» and rope squads is given before that of " report for duty." They march in a body to the destined place and take charge of and push the packed hand or Digitized by Google OPERATION 35 Fio. 15.— Layout for Ascent and Arrangement of £?b^Google 36 MILITARY OBSERVATION BALLOONS other wagons to the place of ascension. They are then ready for the commands of the officer for the preparation. Ascension of a Kite Balloon The Car Squad. On arrival at the place of ascension the material for the balloon squad is unloaded. The car is placed with the long side in the direction of the wind. Nos. I and 2 take the cross ropes and the ascension ropes out of the car^ Nos. 3 and 4 the rope pulley and six coils of pulley lines. Nos. 5 and 6 take the tow line and the tail cups and place them as shown on Fig. 16. No. 4 is detailed to fasten the mooring cable in the cable clamp and the cable damp to the ring of the pulley shackle. The Rope Squad. The mooring cable should, when possible, lie along the ground in a straight line and in the direction of the wind. If this is impracticable it should be either stretched out in a line as straight as possible or else wound aroimd some firm object The laying out of the cable can be accomplished by one of the following three methods: 1. No. 4 of squad No. 8 holds the cable clamp end of the cable, standing at the ascension site, and the cable is unwoimd from the drum by transporting it by the hand wagon from the ascending to the anchoring site. 2. The rope drum is placed at the anchoring site, and No. 4 of squad No. 8, assisted by three men of the rope reserve squad, carries the cable damp end to the ascen- sion site. 3. This method is the same as the first except that the drum is carried by the reserve squad instead of being Digitized by Google OPERATION 37 T Digitized by Google 38 MIUTARY OBSERVATION BALLOONS transported on the hand wagon. This third method is rarely used. Whichever method is used, No. 4 of squad No. 8 gives the cable clamp to No. 4 of squad No. 7 immediately after the cable is laid out The Ascension by Means of a Movable Pulley. (Fig. 16.) Under the supervision of the commander of the ground station the following preparation for ascension with a movable pulley must be made: Nos. i^ 5 and 6 fasten the tree rope to some indicated firm object, such as a tree, or the back axle of the gas wagon. The tree rope is to be wrapped around the object several times until the strain of the balloon falls upon the long sling of the rope, which has an iron ring on it The end of tlie rope is to be fastened for safety to this iron ring by means of a snap hook. The short sUng of the rope has no strain on it Nos. 3 and 4 lay the leather rope lock in the direction of the mooring cable. The damp is then closed and the screws tightened. The ring is connected by means of the S hook to the tree rope. This is done in such a manner that the S hook has the mooring cable beneath it. Nos. I and 3 attend to the installation of the ground station. When the mooring cable is ready for ascension and the telephone connections are made, the commander of the ground station reports to the commander of the car station, " Ascension Clear." Stationary Pulley. (Fig. 17.) For preparation for as- cension with the stationary pulley all numbers march with Digitized by Google OPERATION 89 the hand wagon to the ground station. From 50 to 80 meters of rope are laid out. Two tree ropes are generally used, one for the pulley and one for the damp. The rope drum is about 50 to 100 meters from the rigid pulley. The rigid pulley is handled by No. 3 of Squad No. 7. He ad- justs it and does all other necessary work. The rope lock of the mooring cable is handled by No. 4 of Squad No. 7, Nrr I I I I II I I I I I *■/ •-•-•■o-o-o ^ ^ssJte- ^ Wind DimicnoN ' I ■ t I MooPtiN^ Caamb Rope Fig. 17.— Ascension of a Kite Balloon by Means of a Stationary Pulley. and is held ready about 6 to 10 meters from the stationary pulley imtil the arrival of the balloon. The preparations are the same as those for the movable pulley. No. 6 mans the handle of the rope drum. No. 5 mans the brake band of the rope drum. Nos. 3 and 4 lay the clamp ready and damp at the com- mand. When a strong wind is blowing the mooring cable is laid back of the clamp and is wrapped aroimd a tree or Digitized by Google 40 MIUTARY OBSERVATION BALLOONS other soUd anchorage. The cable can be doubled between the n^ dan^ and the drum and then wrapped around a finn object The rope loop is held with a stake. Two tree ropes and two damps are used. The second damp is handled by No. 4 of squad No. 8. If necessary four men from the reserve squad can be called upon to prepare for ascension. These men, under the supervision of an officer, handle all the '^ by-connections.'^ One man takes charge of the tdephone case and recdvers. Another man follows at a distance of 100 meters with the wire and unreels it. Still another man follows at a distance of 10 meters with insulation materials and testing instruments. His work is to test the connections and repair any trouble. A fourth man with a tree fork and climbing q)urs places the wire in the trees. This line has to be connected to the groimd station while this work is in progress. If it is necessary to aoss roads, a guard must be stationed at such points. Coupling. (Fig. 18.) After the balloon is over the car, and the coupling ring over the toggle of the cross rope, Nos. 5 and 6 of the car squad couple the tail line at the command, " Ready, Couple for ascension." The balloon then ascends until the coupling rings are breast high. If sand bags have been hooked on they are taken off at the command " Uncouple." Balloon Squad. (Fig. 18.) Nos. i of squads 3 aud 4 couple the forward toggles to the cross rope. Nos. i of squads 5 and 6 connect the rear toggles to the coupling rings by means of a knot in the rope loops. After this the same numbers toggle the ascension rope at the command of "couple." Digitized by Google OPERATION 41 291 19 » -AdCCNSION ROF Wind CATCHC^d Fig. 18.— Coupling for Ascension by the Balloon Squad. Digitized by Google 42 MILITARY OBSERVATION BALLOONS Nos. I and a take the forward adjusting ropes and pun them under the cross rope to the car. They then tie them to the loops on the car. Nos. 5 and 6 fix the rear adjusting ropes to the car; this is done by means of the ring. For the coupling of the car to the loop ropes No. i puts the ring on the forward edge of the car and fixes the large toggles. No. 2 gets the forward adjusting ropes and puUs them over the cross rope to the ring and gives it to No. I for coupling. No. i toggles the forward adjusting ropes and the middle toggle. No. 2 helps with the other lines. No. 5, left middle adjusting wpes. No. 5, left rear adjusting ropes. No. 5, left flank adjusting ropes. No. 6, right middle adjusting ropes. No. 6, right rear adjusting ropes. No. 6, right flank adjusting ropes. No. I of squad 2 carefully opens the packed-in rqpping- panel rope and gives it to No. i of Squad No. 7, who pulls it through a ring to the car. Nos. 5 and 6 of squad 7 handle the tail cups, watch the car, and collect the car message-carriers. For the ascension with a movable pulley No. 3 lays the mooring cable in the movable pulley. He puts the pulley about ten paces from the rope lock and then stations himself at that point No. 4 couples the rope lock. Nos. 3 and 4 lay the pulley line in the rope pulley. When ascending with the stationary pulley No. 3 puts the mooring cable in the pulley and the rope squad has the rope ready and hooks it on. Digitized by Google OPERATION 43 After Nos. i and 2 have coupled the car station con- nectionSy they have to see that Uie telephone connections are well insulated at the rope lock. At the command ^' To the ascension ropes/' Nos. i, a, 3, 4, 5, and 6 are arranged in groups at the ascension ropes. Squads i-III and i-IV seize the forward and squads 5-Vn and 6-VII the rear ascension ropes. Digitized by Google CHAPTER IV Tnining of flie Field BaUoon Compaiiy Field Tnmsportatioii and PuUng. The park of a field balloon company consists of: Six gas wagons. One balloon wagon. One rope wagon. One requisition wagon. One ladder wagon. Two provision wagons. The gas wagon and rope wagons are driven, in time of war, by six horses; in time of peace, by four; the requisition wagon is always driven, by a team of saddle horses. The line of march is formed, two abreast, in the following wagon procession: The gas wagons i and a, the first team. The gas wagons 3 and 4, the second team. The gas wagons 5 and 6, the third team. The balloon and rope wagons, the fourth team. Each team is under the command of a subaltern officer; thay are ranked according to the judgment of the com- mander of the balloon company. A reserve squad of men and horses is provided with each company. The nonnal position of a field balloon company is in a 44 Digitized by Google COMPANY TRAINING 46 T ^—w ja aa^ ♦ 4 MouNTeDSAvteiehrr Fio. XQ.-— Posted Compeny. BL H Digitized by Google 46 MnJTARY OBSERVATION BALLOONS dosed line, with the men and drivers mounted, as shown m Fig. 19. The four teams of the company stand in numeri- cal order (that is, the number they have in general service), from right to left, with six paces between, and in every team the wagons must stand next to each other. The span between is to be measiured from the point of one axle to that of the other. The commander stands thirty paces distant from the middle of the company and faces it The team officers stand two paces from the middle of their teams and face the commander. The mounted officer rides behind, then in advance of wagon No. i. The reserve squad and provision wagons are ten paces behind the first line. The reserve squad consists of one immounted corporal and fourteen men who serve as grooms for the saddle horses of the wagons, and the imhamessed reserve horses. Besides these, there are one saddle maker, one blacksmith, reserve drivers, and the servants of the officers. The balloon squads and the immounted drivers are formed in two files, on the right flank. Six paces from these the reserve horses stand, facing the right flank. The corporal stands two paces from the right flank facing forward. The accoimting officer stands one pace to the right of the reserve squad. Duties of Team O&cers. The commander of the balloon company stays at that place where he can best pass judgment upon the formation and maneuvers of his divi- sion. The team commanders must lead the way according to Digitized by Google COMPANY TRAINING 47 the given cominands and stay within a given space^ but they can leave their places if necessary. They give cominands when marching by waving their hands, and make them still clearer by turning their horses, or by changing the pace. Exceptionally they give their directions moderately loud by command; during certain conditions of fighting, such as a sudden attack, the com- manders must use their own judgment to full extent. This holds true also of the squad officers of the second line. Commands, Sword Signals, and Signals. The move- ments of the company are regulated by the conunands, sword signals or signals. The conmiander must, at the beginning of the training, give both the commands and the sword signals. When the training has advanced to a certain degree only sword signals are used. In case the commander wishes to direct by means of sword signals only, he can give these while riding or upon halting. They must be given at a certain distance from the company and from the right place. They are given slowly and dearly, so that they are easily under- stood. The sword signals are as follows: Holding the sward at arm^s length, with the point up- ward, means " Attention.'* For emphasizing, the handk of the lifted sward is turned often in the hand, a little ta the left or right. This signal is to be given before every command, as well as before every sword signal. If the lifted sward is suddenly lowered, with the paint ta the ground, that means ** March, step-march, or halt." Digitized by Google 48 MILITARY OBSERVATION BALLOONS Eveiy oommand is to be accompanied by the swofd signal. The direction of march is given by means of the suford, with arm ouistrdched in the direction to be tahen^ and with the sworffs edge turned downward. For changing to a trot the arm with the sword is extended upward. For changing horn a quick march to that of the usual pace, the arm is held in the same way as for the trot signal^ only that the point of the sword is downward. To change from a trot to a gallop the arm is held in the same way as for the trot signal, but the sword is pointed in the direction to be taken. To slacken the pace the sword is brought forward with outstretched arm in the horizontal position with the blade down and swung slowly backward in a quarter circle. This signal toward the left (right) means the slackening of the pace of the left (right) flank; when given to both sides, that the entire company should slacken its pace. In order to increase the pace of one or the other flanks accordingly, the sword is held out with outstretched arm in the direction of that wing, and is slowly swung backward in a quarter circle. If this signal is given to both sides it means that the pace of the entire company should be in- creased. For swinging toward the ri^t, the commander swings Ms sword in a semicircle over his horse^s head, and swings in curves in the air several times. For swinging toward the left, his sword is swung in curves in the air several times. Should the balloon company turn to the left, then the Digitized by Google COMPANY TRAINING 49 sward is held with outstretched arm aver the heady and swung in curves in the air several times. Should the turn be toward the right then his direction must be first indicated by the outstretched arm and sword. For advancing to the inflating position, the com- mander indicates the direction, lifts the sword to a vertical position and swings the sword sUndy at arm^s length, down- ward several times to the left and right. For marching up a balloon company from the rear on both sides of the balloon the commander must point his sword to the left or the right in front of the center of the front to be taken. For drawing up on the flank the comxnander goes to that side and gives the direct signal for drawing up. After each command and each sword signsd the s^al for execution is to be given, whereupon the execution of the signal immediately follows. For forming a column from the dosed lines toward the front the commander indicates with his sword the line along which the colimm is to be formed and at the same time commands the direction. If the coliunn is to be formed on the flank then this is to be conmianded and the direction signals are to be given en the flank. For forming the march column the conmiander indicates with his sword the wagon from which it is to be formed and at the same time gives the command. If the sword is swung at arm's length once to the left and right of the body, it signifies "Dismoimt or Mount," according to whether the men are mounted or dismounted. Digitized by Google so MILITARY OBSERVATION BALLOONS Applieatioii of Different Pftces. A successful opera- tion of the balloon company can be obtained only when it is able to arrive at the desired place on time. The result is therefore partly based on the training and en- durance of the horses. If the balloon company goes along with regiment bear- ing arms, then the regiment regulates the pace of the balloon company. If it marches alone, then the pace is regulated by the distance to be covered and by the existing conditions in the country to be traveled. The marching pace is the one usually used for marches. The gunners follow their wagons two abreast Upon the command of their officers they march to the right or left or both sides of the wagons, all according to the order of their numbers. y- When preparing for an attack alone, and if the condition of the ground permits, it moves into a trot When advancing to the place of battle, long distances can be covered by intermittent trotting and marching at the rate of about four miles per hour. Diujng the trotting the gunners must be seated on the wagons. The trotting pace is to be maintained as long as conditions permit Tlie gallop is only to be gotten into from the trotting pace. The steadiness of the pace is of great importance. Therefore a pace-regulating officer must be always on hand. Mounting and Dismounting. The mounting and dis- mounting of the details is ordered by the contunands of '' Mount and Dismoimt" All mounted men mount or dismount accordingly. All those who have room for dis- mounting slip two paces sidewise and after the command Digitized by Google COMPANY TRAINING 51 of ** Mount/' take their places again. Should the gunners only take their places, then the command of ** Gunners mount or dismount " is given. The Nos. i, 2 and 3 sit in the front No. i moimts from the right; 2 and 3 bam the left; 4, 5, and 6 sit facing the back; 5 and 6 mount from the left side and 4 from the right side. Every man holds his gun in the outer hand, holds on to the handle of the wagon with the hand toward the wagon, places the forward foot on the running step and then on the footboard of the wagon, and then sits down. The gun is placed between the feet with the muzzle upward and is held with both hands. When the march commences, those sitting on the outer side seize the lines and the middle man links his arms through the one next to him, etc., and they then place their feet firmly against the foot- board. Upon the command of ^^ Gunners Dismount " the men get down on the same side that they were sitting, those on the outside getting down first. Maneuvering. The dressing of a front line of a balloon company must always be done toward the front. For that reason the men of a company must halt at least a wagon's distance behind the front line which is to be overtaken. The command of ** Right or Left Dress " is then given. The company dresses according to the guides. Upon the sword signal of march the wagon columns precede the commanders and take the distance at intervals according to their column leaders. Line No. 2 closes up to line No. i and takes the distance and direction. The indicated direction of march is given by the commander of the company by means of any perceivable object, or Digitized by Google 6& MILITARY OBSERVATION BALLOONS by outstretched ann and riding in the desired direction. The other column commanders must follow at the same pace as that of the direction commander, and at the same interval. The mounted wagon drivers of every column must overtake the distance and interval of their commanders. They must follow the pace and direction of the column com- manders. The middle and perch men must see that the pace of their horses is increased or slackened and that outriders follow the column commanders at the right pace. During a front march less attention is paid to the exact direction than to the straightness of the march. The front march must be done by marching and trotting. This is to be practiced as much as possible. Land obstacles which cannot be gotten over by the single teams or wagons must be driven around under the com- mand of the conmiander without interrupting the proces- sion of the neighboring ones, and must come back into their places as quickly as possible. For carrying out the front march the command of " Forward March," either step or trot, is given. The commander of the front wagon column takes charge of the direction of the march. If the commander must, which is very rare, give the commands for the direction of another column, then the command of " Direction — Column Step, Trot, March," is given. The commander supervises the keeping up of the direction of the march through the commanders of the colimms, as well as the proper driving of the colimm and wagons. This is done best from a position in the rear. Digitized by Google COMPANY TRAINING 53 The holding in of the front and an even swift marching pace are best supervised from the side. In order to change the line of march from a straight one to that of a 45^ angle the command of right or left " obKque " is given. The commanders of the coliunns at the same time make a half turn and march in the direction of the column, so that aHsassHn r 1 T 1 r 1 r 1 T 1 r i r 1 r i Fig. 20.— Right-Oblique Movement. the column, wagons and commanders remain parallel to the former front line. (Fig. 20.) Upon the conwnand of " Forward March " the former attitude is to be taken in the new direction. Wheeling. The changing of direction of march by means of wheeling is done at the most convenient angle, which must not be over 90°. For wheeling in closed lines, the commander gives the Digitized by Google 54 MILITARY OBSERVATION BALLOONS balloon company during the march the command, ** Right, left (half right) wheel, step, trot, march.'' During the right wheding the right, and during the left wheeling the left wing, is called the pivoting wing; the other is called the fluctuating wing. FiQ, ai.— Wheeling Movement The pivot turns upon a circle whose diameter to the inner advance horse measmres 20 paces. The groimd which is covered by this circle is determined by the new direction of the march in view. (Fig. 21.) The other teams turn, led by their commanders, keep- ing the before-mentioned interval from the pivot Digitized by Google COMPANY TRAINING 55 MiM f f 9 f Fio. 33.— Turning Axoiind. Digitized by Google 66 MnJTARY OBSERVATION BALLOONS Tlie wagon procession of the fluctuating wing must proceed a certain space at the beginning of the pivoting, so as to prevent a shortening of the interval. The commanders of the team stand facing the front during most of the pivoting. The pivot must during this movement keep in step to increase or slacken the pace. In a column the back part of the column swings aroimd to the pivoting point of the front When the wheeling wing is at horse's distance from the new front line, the commander gives the command, ** Direc- tion." Whereupon the march is resumed at the original pace in a straight direction. Turning Around. The turning or formation of the front in a closed line is done upon the command of ''Turn, right, step, trot, march. For ending the turning or for- mation it must be done in time by the seasonable command of " Forward." (Fig. 22.) Inflation Place. The formation of the company for inflating and placing of the balloon is called the place for inflation. (Fig. 23). The company forms itself into two divisions: The first three teams and the gas wagons i to 6 stand in front in order of niunbers: the fourth with i balloon and rope wagon in a closed line about 50 paces in the rear of the gas wagons. 1. The first team stands in front in a closed line with one step interval in the direction given out by the com- manders. 2. The second team rides to the right. 3. The third team to the left of the first Digitized by Google COMPAI^ TRAINING 57 5V\ Fio. 23.— Inflating Position. Digitized by Google 68 MILITARY OBSERVATION BALLOONS The distance between the teams and between wagons must measure one pace from aide to aide. The commanders of the teams stand two paces in front of the middle of their teams. The drawing up of the four teams is to be adjusted to the groimd condition. For drawing up upon a small space no definite formation is given — and the best formation is left to the judgment of the commander. During the inflation the commanders of the first three teams must dismount and give their horses to the outrider of their team. The driving up to the inflation position is done from the march-column to a column. In necessary cases it can be formed upon a place out of the dosed lines, in which case the fourth team drives back to the line and the other teams proceed to their places. The commander directs from his position the direc- tion and the middle of the drawing up of the first division. The drawing up takes place upon the command of '' Step, trot, — ^march, forward " of the company commander with the simultaneous sword signal. Following this command the first wagon of the marching column must halt upon the signal of the commander of the balloon company; the second is ordered to advance to the right forward with one pace interval. The rest of the wagons drive singly into their positions. The changing from the column position into the inflat- ing is done in teams. The four teams march in a closed line, advance 30 paces in the same direction as before, and are then ordered by the Digitized by Google COMPANY TRAINING 59 commanders of the teams to turn aroimd and proceed to their places. Direction for the Column. The colmnn can be formed upon one of the flanks to the front or side, upon standing or during the march. The coliunns form a dosed line when standing in sections, according to the space and in the commanded place, one after another. During the move- ment the leading column keeps its own pace or takes the pace as ordered. The rest of the sections await the last, remaining standing, and line up slowly in back of the lead according to their order. In case the formation is done during the marching in trot, sidewa3rs, then the head colxmm to prevent the others from getting behind, must advance forward a wagon's length before the swinging is begun. The formation of the coliunns from the inflating posi- tion is analogous to that of the closed line. During the movements of the coliunns the leader of the first section of the column gives the direction. During the march, the distances (intervals) can be changed by the command, " Distance, interval in steps, step, trot, march." The intervals are to be adjusted in comparison with the team commanders. When the road is narrow the mounted charges march in front of the wagons. The development of the column is usually done in trot. During the movement the leader marches in time or slackens his pace. The single sections of the columns, after they have formed, take the pace of the lead and after the advance has been completed they take the former pace, at the same time as the commanders of the " Direction Teams." Digitized by Google COfi MIUTARY OBSERVATION BALLOONS i>a The commanders of the teams must see to the direction and be assured that the front line is correct, leading their teams the shortest way to the front. The March Cohsnms. (Fig. 24.) The wagons in the march columns follow singly at a distance of three paces; the distance is to be measured from the back of one wagon to the head of the advance horse of the following wagon. The wagons in the march colimm are num- bered from front to back; disregarding their service numbers, using whichever number happens to fall to them according to their momentary position. For formation of the march colmnn in iSank to the front or side there are given the commands of March Colunms f right, left, forward. \ right, left. Step, trot, march, direction. Out of a closed line or out of an inflating position the wagon in question takes the direc- tion; the other wagons start the movement when there is room to file into the marching colimm. The change from the col- umn to the march column is made in a similar way; every following team files itself at the necessary distance behind the le^ team. . 24.— Marcb C^umn, Digitized by Google COMPANY TRAINING -61 ^, , _ . f forward. C^°^^^l right, left forward Trot, march, direction. The team commanders go quickly in front of their wagon teams, cause these to draw up, and lead them to the front. The head wagon proceeds straight forward at the same pace as the team commanders. The second wagon ad- vances to the front in a trot to the drawing-up side, slowly, to the before-mentioned interval, and takes the same pace as the team commander. The following wagons must take the corresponding tuming'for crosstQg to the drawing-up side. During the development, i and 2 team march to the right forward and 3 and 4 left forward, and the teams move to their corresponding drawing-up side to the front. The development on a flank is done upon the command of ^^^^^ ^^M Half left and half right Step, trot, march, direction. In a closed Une at the order of commander of head team the first wagon turns in the given direction and goes quickly to the new position. The second wagon proceeds straight ahead tmtil it arrives by taking the corresponding txun, at the prescribed interval, in the new front Une, when it takes, like the first wagon, the pace of the team com- manders. The other wagons march up in teams to the side com- Digitized by Google 62. MILITARY OBSERVATION BALLOONS mand and are led by the corresponding turning to the new front From crossing into the inflating position on a flank, the lead is commanded to swing in the required direction and then the commands for marching up and for placing for inflation are given. Columns. In the columns the single teams follow ten paces apart This distance is measured from the back of the front wagon to the head of the advance horse of the following wagon. In every team the two wagons drive next to each other at an interval of six paces. The team commanders ride two paces in front of the middle of their respective teams. The first (front) team commander has the command; the other mounted charges, eventually divided, remain in their places. For forming of the colxmm upon a flank forward or to a side, the command is given nr.u.^r. I "8*^^' ^^^^> forward. ^^^"^1 right, left Step, trot, march, direction. The remaining columns swing according to their niun- ber to the given side and follow the lead. The wagons denote the necessary interval. For passing from the march colimms to the squad coliunns the column commanders go to their coliunns and proceed in the given direction. During development the first colxmm marches during the pivoting. The other column completes the advance and pivots only at the pivoting point of the head colxmm. For developing forward toward both sides or to one side the command is given: Digitized by Google COMPANY TRAINING 63 Closed Line {J^^^fjj^^^ Step, trot, march, direction. The command of the colimm division of the lead goes straight ahead or takes the new direction. These two wagons set the interval during the procedure. The rest of the wagons are led to the side imtil they have reached the corresponding interval, whence they proceed straight ahead. The leading team swings immediately in the closed Une, while the remaining teams march off, in order that enough time may be allowed for turning in the new direc- tion and the lead to the front. When drawing up before a sloping (or oblique) place, the teams settle the distance to the left diuJng the drawing up toward the right wing team. For development into full position in a wing, the leading team is ordered to turn in the direction in question, and then the command is given to draw up in the full position. Ceremonies. The balloon division is formed in a dosed line for reviews. In case a balloon division stands with other troops, if there is room enough, it takes a position at a distance of fifty paces from the latter. In a dosed line,the commander stands thirty paces in the coliunn, ten paces in front of and fronting the division. When the reviewer arrives, the commander of the troops orders the bugler to soimd " Attention," and as soon as they are thirty paces from the reviewer, commands ''right dress"; whereupon the commander reports the number of wagons. Digitized by Google 64 . MILITARY OBSERVATION BALLOONS n the rank of the reviewer demands the sounding of the general march, then the bugler must at the command of ** dress " start the same and may only stop when the commander commands '' Halt/' or orders this by a sword signal. The division commander salutes after he has commanded the turning of heads and takes his place after the reviewer is thirty paces past the division. In case the reviewer wants to inspect the back lines of the balloon division the conmiander must give the command at the same time of the head-turning. " Second line, left (right), dress." Marching Past In marching past, the balloon division forms a dosed Une or into colimms. The commander of the division is two paces in front of the middle of the line of the team commander. The division commander gives the command of " March past, right, left," according to the formation. The commander commands the turning of the head at about thirty paces from the passing point whence the bugle starts to blow the general march and continues imtil " Care " is commanded, which must take place when the balloon division has gone thirty paces past the reviewing point. The team commander does not execute the turning of the head at the reviewing point. Charges and privates take the described position, and in passing face the reviewer. Digitized by Google CHAPTER V Inflating and Handling of a Elite Balloon During Maneuvers. Duties of the Balloon Squad. Duties of the Car Squad; of the Rope Squad. Balloon Transport, with Ascension Ropes; Transportation Ropes. Aid of Crew. High Trans- portation. Marching Order of the Balloon Transporta- tion. Lifting over Obstacles. Deflation and Refilling of the Balloon. Inflating and Attendance of a Kite Balloon The attendance of a balloon is the same as that described in Chapters VI, VII, VIII. Inflation. For inflation the men march up and dis- moimt. The dismoimting must take place at a level place which is sheltered from the wind and hidden from the enemy. Balloon Squads. Upon the command ^' Lay out bal- loon" Nos. I, 2 and 3 must do the following: No. I opens the locks and throws back the box cover. No. 2 lets down the tail piece. No. 3 takes the back footboard and puts it on the right back wheel; i, 2 and 3 take the back seat off and put it the same way on the left back wheel. No. 2 takes the hand mallet, the screws and valve keys and places them on the cover of the valves. Then Nos. i, 2, and 3 make hose connections with the joining pipe by means of a wrench. In case the connect- 65 Digitized by Google 66 MILITARY OBSERVATION BALLOONS ing hose does not reach from the wagon to the joining pq>e, then the hose Nos. 2 and 3, if necessary must connect the wagon to the joining pipe and the reserve hose. In connecting the hose the hand mallet must first be siezed by No. i, the coupling being done by light blows, and then given to No. 2 and to No. 3. Then No. i stands to the right of the gas wagon, while No. 3, after having placed the hand mallet upon the cover of the requisition box, stands to the left of the connecting hose and back of the wagon, facing the hose. Then No. 2's step to their groups, No. i and 2 of Squad 6, after they have finished with the work of their wagons, go to the joining pipes and take with Nos. 4, 5, and 6 of the car squad, the laid-down reserve hose, the inflation hose, inflating pipe, reserve filling hose, and the soft ropes. Upon the command of *' Lay out Balloon," Nos. 4, 5, and 6 of the various balloon squads go to the balloon wagon, taking their places according to Fig. 25, in three sections facing each other, so that like niunbers are placed in order. Under the supervision of the balloon officers, and with the aid of squad No. 7, they imload the balloon, together with the blanket, in such a way that Nos. 4 of the I and 2 squads seize the balloon near the valve and pull it toward the given direction from the wagon. The remain- ing numbers of the z and 2 squads place themselves at three-pace intervals under the balloon; the; irest of the squads then follow. The men must stand under the balloon in pairs and place their inner hands upon the shoulders of their com- panions. In this way they make the carrying of the balloon easier. The balloon, whidi has been lifted from the wagon. Digitized by Google MAMEUVERING 67 vmi anna so 40 60l o--« *o 4TBAM Fig. as. — ^Iiifl»dan I Digitized by Google 68 MILITARY OBSERVATION BALLOONS is brought in such a way to the free end of the inflating hose that the filling pipe, after the balloon has been laid out and the hose stretched, can be shoved into the appendix. The balloon officer commands " Halt," as the balloon stands with its valve toward the wind. Then " Put up," when the envelope is stretched open. Then ^Xower the Balloon." The folded envelope is let down, the squads kneel upon both knees and are ready to unfold the balloon. The unfolding takes place upon the conmiand of ^^ Lay out right (left)," in such a manner that the upper layer of goods together with the blanket is unfolded by the men who are kneeling at the right and left After unfolding, the loops must be pulled in and laid ready. Nos. I and 3 of the sixth wagon buckle the inflating hose to the connecting pipe in the meanwhile. The other end of the inflating hose, together with the filling pipe, is shoved as far as possible into the appendix of the balloon, and is tied with a soft cord. The filling hose must not become kinked and should be stretched only a little. The reserve inflating hose is placed next to the inflating hose. The men stay imder the balloon during the inflation. (Fig. 26.) During the inflation No. i of Squad i serves as inspec- tor and stays upon the side farthest from the wagons. The gas tank of the first wagon is opened by No. 2 of Squad No. i. When all preparations have been made the balloon officer gives the command of " Inflate." Nos. I of the first five gas wagons open the valves of the right gas tanks of the upper rows. The next valve is Digitized by Google MANEUVERING 69 Digitized by Google 70 MILITARY OBSERVATION BALLOONS to be opened only when the preceding one has been partly emptied. In case a valve blows very strongly it is to be dosed without necessary commands. The tanks can never be entirely emptied on accomit of the diminishing pressure from within. The balloon officer regulates the inflation by a signal whistie and by waving his hand. By a shrill whistie he calls the attention of the men at the valves. The lifting of the right hand commands the hastening of the inflation. The lowering of this hand is an order to inflate more slowly. When he whisties twice and at the same time swings his hand over his head the inflating must be stopped. Every man is ordered to report a serious gas leak as soon as he notices it. The inflation is to be suspended when there are still 50 cubic meters lacking for the entire volume. This is because the gas coming from the tanks has a considerably lower temperature than the surrounding air. In case five gas wagons are not enough for inflating, then No. 6 must be pulled up in line. During the inflation the balloon squad must gradually let the balloon up on the rigging, according to the increasing inflation. For ending the inflation the same signal is given as that for continuing inflation. Duties of the Car Squad. Upon the command of ^' Seize the Requisitions " the locks are opened by No. i; No. 2 lowers the hull lock. Nos. 4, 5, and 6 fasten the reserve inflating hose^to the joining pipe and place it upon the right Digitized by Google MANEUVERING 71 side of the wagon. Then Nos. 2 and 3 pull the p^ out of the back footboard so that it falls down. Nos. I and 2 open the cover of the wagon, No. 3, takes off the back seat and uses it as a prop for the cover. No. 4 takes the filling pipe, the inflating hose, reserve inflating hose, and soft cord from the wagon and places them, together with the joining pipe and the reserve hose, at the same place where Nos. 5 and 6 had placed the connecting pipes. As soon as the envelope of the balloon has been taken out of the wagon the backboard is placed in again, and the cover of the wagon is locked by Nos. i and 2. The back seat is put up by No. 3 The car squad marches to the rope wagon and carries the car and its equipment to the balloon, pladng it where indicated by the commander of the division. It is set with its long side to the wind, when preparations for coup- ling are started. The Rope Squad. Upon the command of '^ Seize the requisitions " the locks are opened by No. i. No. 2 lets down the sprag and with No. 3 pulls the bolt out of the back footboard so that it hangs down. Then Nos. I, 2, and 3 open the lid, propping it with the back seat, take off the backboard and place it upon the front foot- board. Then these numbers unload the car and its equip- ment. Nos. 4, 5, and 6 put it upon the ground next to the wagon from where the car squad take it The commander of the second groimd station leads the rope wagon to the spot a^^inted for the anchoring of the mooring rope, which is then laid out. The coupling for ascension is done as previously de- Digitized by Google 72 MILITARY OBSERVATION BALLOONS Bcribed, or by two men from the balloon squad who must be replaced during this time. Balloon Tr/insportation Ways. The transportation of an inflated balloon can be done in the following ways: Bigji transportation with or without car. On the ascension ropes. On the transportation ropes. Eigji transportation by means of the mooring rope. Carrying Out the Transportation. Upon the command of " Balloon, transport, direction, march," the movement for transport is begun. The halting of the movement follows the command of " Halt/' The speed for transporting is decided by the strength of the wind, the condition of the terrain, and the strength of the crew. In order to have reserve and anchoring material at hand, under difficult conditions, every transported balloon must be followed by a hand wagon loaded for these re- quirements. This wagon must be sent out for the preparing of the anchoring, only when it is seen that the baUoon is reaching its destination. Should the weather or the terrain conditions make it impossible for the full crew to complete the transport the balloon should be temporarily anchored. The cutting open of the balloon is allowed only at a time of great danger and only when the order is given by the Balloon Officer. Digitized by Google MANEUVERING 73 Low Transport In makbg a low transport the ground must be free from obstacles, especially during a high wind. Low transporting in a high wind is done only for short distances. This method of transporting is used when it is desired to conceal the movements from the enemy. The balloon is weighed down by sand bags, and when transporting a kite balloon the crew seize the rigging when moving a spherical balloon, the crow-foot netting. The kite balloon is transported with its head in the direction of the wind. No. i-i holds the head in the wind. No. 1-2 carries the valve and ripping line. Nos. 5 and 6-5 and 5 and 6-6 prevent the torus from dragging. When transporting the spherical balloon, No. i-i takes the direction and No. 1-2 carries the ripping line, the valve line and exchange cord. The nimibers 1-3, 1-4, and 1-5 carry the ring and the ascension (lifting) ropes. No. 1-2 has to see that the ropes are not pulled. This detail must hold the ropes under all conditions, and in the moment of danger, has to be ready, upon command, to rip open the balloon. Transportation with Ascension Ropes The transport with the ascension ropes is done only for short distances and when the car has been coupled on. The balloon is let up with ascension ropes to the required height, and then the transportation follows. Digitized by Google 74 MILITARY OBSERVATION BALLOONS Transport with the Transportation Ropes, with An) OF Crew The transporting of a balloon with the tranq>ortation Topes is the usual way of moving an inflated balloon for a long distance. The transport of a kite balloon is done with or without the car. When the balloon is conveyed without the car it must be weighted down with sand bags, to assure main- taining its kite position. The sphericEd balloon is usually tranq>orted with the car coupled and fastened onto it and its crew in place. Three tranq>ort ropes, 50 meters long, for kite balloons are fastened in the ring at the hoop of the pulley; in a spherical balloon to the coils of the ring by means of a secure knot The ascension ropes are left on the balloon. The preparation for transporting with the ropes is done by the car squad. (See Fig. 27.) The tranq)ortation ropes are laid out in acute angles in the direction of the wind, placed at the necessary dis- tance from the desired transport height, and with two traction ropes. The balloon is then let up until the transportation rope is taut when the crew are ordered accordiog to their nrnn- bers. Upon the command of ''Up with the transport line," the balloon is raised and lastly the crew is arranged at the traction ropes, according to their number. With, the Aid of a Vehicle. For relieving the men the transportation ropes may be fastened to a heavily har- nessed wagon. If the wind is blowing from the side, the Digitized by Google MANEUVERING 76 "^^s^Z^X^.. Fig. 27. — Preparation for Transport Digitized by Google 76 MILITARY OBSERVATION BALLOONS force of the wind must be lessened by holding the r(^>es toward that side. High Transportation with Mooring Rope Kgh tranq>ortation with the mooring rope is done when the observation of the ascended balloon is not to be inter- rupted, when the balloon is shot at, or when the transporta- tion leads through woods, in which case it would be diffi- cult to advance with the use of transportation ropes. For accomplishing high tranq>ortation with the mooring rope, the eyelets of the clamps, which hold the mooring rope by means of S hooks, are to be equipped with traction ropes which are held by several of the crew. After the movable pulley in front of the damp has been held by a sufficient force the tree rope is loosened, after which, with the aid of the extra help, the balloon is held fast to the traction rope of the damp and pulley. The rope drum, the tree rope, and the telephone con- nections are brought by the rope squad on the hand wagon. In case a harnessed heavy wagon is at hand, the damp can be fastened to the back axle by means of a tree rope, which will make transportation easier. Marching Order of the Balloon Transportation A mounted officer precedes the balloon and indicates the way by signaling or by calling out The advance patrol, composed of the reserve or car party, proceeds at 100 paces, with climbing irons, mallets, ladders, and plum- mets. The advance i>atrol must remove any obstade which has been pointed out by the officer. Digitized by Google MANEUVERING 77 The commander in chaige goes with the balloon. Ten i>aces back of the balloon is a petty officer who has to keep the marching discipline and to watch the back part of the balloon. LnriNG THE Balloon over an Obstacle The lifting over telephone wires and similar obstacles during transportation with the transportation ropes Is done as follows: The balloon is brought as near the obstruction as possible and after removing the traction rope from the transportation ropes, the latter are lifted over singly, either with the aid of the plunmet, the two^ pieced fork, or the three-pieced ladder. Two transporta- tion lines are to be held taut at each side. In a spherical balloon the car squad takes the free transportation line into the car and throws it over the obstacle. The arrangement of the crew of the balloon squads at the ropes is to be regulated by the officer in charge. In case of necessity during the throwing of the free rope over the obstacle, the crew of the other transportation lines can be called upon. After the rope has been thrown over and after the trac- tion ropes have been fixed, the crew are ordered to their previous positions. The last rope which is still free is brought over the obstacle as were the others, or it can be thrown over the obstacle by the crew, who march in and then pull it over. This is done when the telephone wires are crossed. Sometimes, when balloons are brought across by high transport, telegraph or telephone wires are pulled down, and afterward repaired by four men, two of whom have Digitized by Google 78 MIUTARY OBSERVATION BALLOONS climbing irons. Sometimes it is advisable to change the course of the telephone wires. When the wires cany elec- tric power, the commander must see that the necessary precautions, such as disconnection of the circuity etc, are taken. When a number of such places are to be crossed it is best to have a wagon at hand which is equipped with the material necessary for repairing of wires. In case the telegraph wires must be crossed, in high tranqx)rtation, the wires can either be cut or their course changed, in which case they are to be put back again as soon as possible. Deflation and Refilling of the Balloon The deflation of the balloon is for the purpose of letting out the gas which has become useless by losing its power of lifting. For deflating a kite balloon the two deflating openings on the sides are opened. The balloon is pulled up in front and let down in the back by the men stationed around it. The valve must never be opened. This valve is to be covered with a cap before deflation. It can be covered with a car blanket and rolled up from the front toward the back. For deflating a spherical balloon the ripping panel is to be opened. In case the carrying gas of one balloon is to be emptied into another, the one which is to be filled should be pre- pared as for an ordinary inflation. The appendices of both are to be connected by the filling and refilling hose and made gas tight by tying up with a soft rope. Four men must do this filling. Digitized by Google MANEUVERING 79 A kite balloon is deflated by rolling it up, a spherical balloon by pulling evenly on the net meshes. In transfusing a spherical balloon the ends of the large crow-foot lacings are tied together with a rope in order to lock the net at the lower end. The sand bags on the balloon being filled are to be spaced equally and the same process is followed as for deflating another balloon. Digitized by Google CHAPTER VI The TTie of a Kite Balloon in Time of War. Purpose of a Balloon. The balloon is a high-moving observation station, which can change its place whenever required, and can be used on the battlefield as well as in other positions. On account of the limited horizon and on accoimt of the dq>endence upon the weather conditions, the balloon cannot replace the activity of the other arms; but can surpass them in some important wajrs. The main purpose of the balloon is to report the con- dition of the battlefield and after battle. Balloon reports do not show the results of a battle, but call the attention of the commanders to the existing situation. The reports have the character of a situation report The general results of the artillery fire can be judged from the balloon. For the purpose of observing the artillery situation and reporting the results of artillery fire^ the balloon is an im- portant factor. The Observation Horizon. The observation horizon is dependent upon the ascension height of the balloon and the weather conditions. Kite balloons ascend under favorable weather conditions (wind blowing up to lo meters per second and fresh gas) to a distance of 500 meters and spherical balloons with wind at 5 meters per second to 600 meters. 80 Digitized by Google IN ACTION 81 With strong windi especially a gale (over lo meters per second) the kite balloon goes to 300 meters but the spheri- cal balloon cannot be used at all. When the wind is blow- ing over 15 meters per second the balloons cannot be used During clear weather an observation in the circum- ference of 10 kilometers can be expected. The finding and distinguishing of stationary troops must be done at a much nearer distance. Diuing a heavy fog, rain or snow, observations cannot be madeJ Balloon Observations. Balloon observations in gen- eral meet with various difficulties. In a dosed country they are greatly hindered. In woods and distant places the observer has no clear view. With the sun in the back the observation is easier then when facing the sim. Station- ary or hidden troops are much harder to find than those marching or stationed in a clearing; dust or smoke and dark backgrounds hide the observation. The observer is frequently misled through the fact that such things as plants, swaying hedges, bushes, orchards, etc., are oft^ mistaken in gloomy weather or misty atmos- phere for troops or fortification lines. Doubtful cases are decided only after renewed observations from both sides of the car, and comparing with the coimtry. The uncer- tam reports, charts, or maps, are to have a question mark placed after them. The observation can be reported in stationary places by ^ving the fitting balloon signals. In order to use a balloon to advantage the conditions of the observer's side as well as that of the enemy's must be known. In stationary positions the balloon observer must especially during the preparations make frequent ascen- Digitized by Google 82 MIUTARY OBSERVATION BALLOONS sions to obtain an exact idea of the terrain to be observed. The acxniracy of boundary reports and reliability of obser- vation of results of artillery fire are essential to success. A balloon observer must have strength of vision, resbt- ance against the swinging motion, be quick at getting his bearings, be able to understand the situation, cahn and conscientious in sending oS his reports. He distinguishes the essential from the non-essential. Balloon reports must never contain secondary details. Only that which has been dearly seen is to be reported. Uncertain reports are to be marked as such. The using of rough sketches and marking on maps is of advantage, as mistakes cannot be made as easily as by telephoning. Usually two officers can be taken up, the observer and the balloon commander. The latter must have been trained for airship service. To him falls the care of the balloon and the correspondence service. A balloon observer can be appointed if necessary. The balloon commander must aid the observer according to the feasibility of the observation. In case only one person can be taken up, he must be an officer trained in the airship service. He proceeds upon these two named duties, hence the observation from the balloon must naturally be interrupted occasionally. It is the duty of the observer to change the height and place of the balloon. In case the officer is wounded or becomes unfit for service he must be relieved. Relieving the observers natiurally causes an interruption in the observation, as the new observer requires time to get his bearings. Service for the Car Station. The conditions seen are Digitized by Google IN ACTION 83 to be reported by sketches or cutting pieces out of maps. These are to be enclosed and thrown off in the carriers or they are telephoned or signaled by the balloon pilot to the ground station. Services of the Ground Station* The ground station must alwajrs, without interruption even during the balloon's transportation, be ready for receiving the reports, which are to be picked up by an officer and rq)eated, as a record to the car station. The names of the locations are to be looked up on the map. A report by telephone does not have to be changed. The maps must always be handy on the ground station, for marking the reported situation. The ground station must, if necessary, make several copies and dispatch them. Petty officers are to be used only occasionally as clerks, and then with great discretion. No one is allowed to question the observer except the com- mander to whom the balloon is entrusted and the com- manders ot the balloon division. Calling the observer should not be pennitted, as it interrupts the observation. The dispatching of reports must receive careftil attention. Next Station. In fortification warfare better service for the commanders is made possible by the establishing of additional stations by the superior commander, or by a connection with an existing telephone network. In field warfare the telephone connection is likewise to be tried; if not, the reports are to be dispatched by officers, messen- gers (mounted), or bicyclists of their own squad. All the officers in service in the balloon division must study the plan of the battlefield before the balloon is put into service, so that the observation and dispatching can be readily accomplished. Digitized by Google 84 MILITARY OBSERVATION BALLOONS Signals. The visual signals are given mostly for artil- lery purposes from the balloon car, and are limited only to the control the firing. They are as follows: Red disk (flag), up. "W/' Red disk (flag), down. "K." Red disk (flag), turning in a drde, gunner aiming straight. White disk, turned toward the right, "r." White disk, turned toward the left, "L" Both flags turned up, higher. Both flags turned down, pull in. Both flags turned horizontally, halt. In case the air is misty or the balloon is at a great distance, or for lengthy reports, or in case it cannot be done by telephoning, the signals are ^ven from the ground station in the customary way with fort artillery. Changing of Position. One stays as long in a place as the progress of the battle necessitates. In case this changes its position or in case one wishes to get another view- point, the change must be made quickly. If the order of the commander is not received in time^ the change of position must be made known to the command. The commander of the balloon division must change upon his own responsibility the position when the battle starts, or in case of a sudden decision for the purpose of discovery or to make the hitting of the balloon more difficult for the marksmen, and must report such change. The shooting of a balloon can very often be made very difficult by simple maneuvers such as ascending and descending. In case a change in position is to be made at such a time, it must be done quic^y and when possible in high transportation. Digitized by Google IN AcnoN 86 The technical manipulations for leaving and going to another place, colliding with troops, and the interrupted observations, are things which are carefully to be con- sidered. Balloon Transport* Diuing war it is often necessary to transport the inflated balloon long distances. The manner of transportation is decided by the existing situation — the weather conditions as well as the strength of the men. It is done as shown in Chapter V. During the transport the balloon and rope wagon (with the balloons for forts, the wagons with the necessary equipment) must follow the balloon. Balloon Escort and Dispatches. Every troop com- mander to whom a balloon is entrusted must under all conditions see to its safety. The squads, if not the balloon division, must be assigned the necessary escort. In danger- ous conditions men whose arms are to be brought to them by wagons may be added for strengthening the escort of the balloon squads. The commander of the balloon division has to take charge of, and is not relieved under any conditions from, safe transport on his own responsibility, whether the regular escort of the balloon is in attendance or whether men from the next troops have been added. An infantry detachment is usually sufficient for an escort. The balloon escorts guard the ground station against a sudden attack and must also guard the wagon division within that district. The commander of the balloon escort studies the loca- tion and posts the guards at the most advantageous places for the protection of the balloon from the sudden attacks Digitized by Google 86 MIUTARY OBSERVATION BALLOONS and in the best protected places from the enemy's fire. He also dispatches small patrols. If there is no infantry in front of the balloon, the ad van ce of the enemy is to be stopped by the escorting patrol ad- vancing about 600 feet in front of the balloon. In case the balloon division retreats after an attack, the escort must protect the balloon until it is safe. Dispatch riders can be demanded when necessary. Technical Preparations and Directions. The time required for the technical arrangements depends upon the training of the men and the weather conditions. The usual time is a. Fortification Balloon Division: Equipment for the inflating station about 6 hr. Inflating the balloon 12 hr. G>upling and ascension 10 min. Descension 10 min. Uncoupling and placing the equipments. . 120 min. Disconnecting an inflating station 3 hr. Balloon transport per kilometer 15-20 min. During a wind over 10 meters per second it can be done only on open ground. b. Field Balloon Division: Spreading balloon, about 5 min. Inflating, about 15 min. Coupling and ascension, about 10 min. Descent, about 5 min. Uncoupling, about 5 min. Placing the equipments, about 15 min. Every balloon division must have a day book. Digitized by Google IN AcnoN 87 Uses of the Balloon Division in FoRxmcAiiONS a. General determination. During battle at a fort, the fortification balloon division can be used. It is an economic administrative subdivision of the fort artillery, stationed at that place and in service under the orders of either the commander of the fort or the commander of the defenders, who use it for artil- lery observation, as well as for tactical piuposes. For the artillery purpose the division is disposed according to the demands of the individual section artillery commanders, eventually to the entire appointed battery division. The oldest ranking commander of the balloon division serves at the same time as relief to the fort commanders. The following must be considered when using a balloon of the fortification balloon division. a. Choosing and establishing an inflation station. b. Choice and reconnaisance of ascension place. Inflation Station. For the establishment of an inflating station the same rules hold as described in Chapter V. In winter it is feasible to place the gas apparatus in a shed. The commander of the fort balloon division regulates the service of an inflating station. Inflation stations which are equipped with steel tanks containing mixed gas, such as are often found in forts, do not require long preparations. Ascension Place. The place of ascension is decided upon from tactical requirements after clearing, the special demands at the time, and also the condition of the coim- try and weather. The place for ascension should be in- visible to the enemy, allow free movements, and be on Digitized by Google 88 MILITARY OBSERVATION BALLOONS obstacle-free ground, so that the balloon can if necessary change its place. The place for assembling should be out of range of the shrapnel of the enemy; that is, at least 4000 meters distant from him. In case it is necessary for closer observation, and in case the battle conditions demand it, the ascended balloon can be brought nearer to the enemy. For clearing up a tactical situation, or to determine the results, it is wise to keep the balloon as near as possible to its escorting troops. For observing the results of gunfire, the best position for the balloon is in the rear of the middle of the firing battery. The firing can be done by night and by electrical illuminaticm of the goal. Then the place of ascension can be chosen nearer to the goal and in the (^posite direction from the searchlights. Choice of Inflation Station and Ascension Place. The commands for choosing an inflating station must be given in time to the commanders of the balloon division, so that all material can be brought to the inflating place twenty- four hours before the balloon is to be used. The commander of the fort must make the following known to the commanders of the sections: The service of the balloon division, time and place for preparation, and the necessary transportation material. The superior commander reports the saf eness and the incidental conditions of the inflating station. The commander of the balloon division with another officer locates the position and notes all detaOs for the placing of the inflating station, and the way of reaching it, and sends a sketch of it to the higher commander. The superior commander then arranges the establishment Digitized by Google IN ACnON 89 of the inflation station and decides when, where and for what purpose the balloon is to be used, and from where and how the necessary material is to be transported. Enough time remains during the inflation of the balloon for the reconnoitering of the ascension place and the trans- port poles for the inflated balloon. The telephone con- nections can also be made during this time. Exploring. The commander of the balloon division, the observer, and the pilot must know the exact situation and the pxupose to be attained by the balloon. During an attack on a fort the necessary directions are usually given by telephone. Attack In GeneraL The divided balloon division at a fort must during the first part of the attack do observation duty only. A regular balloon observing service is installed only upon the arrival of the fortification balloon division, which is due with the besieging artillery. Duties of the Kite Balloon. The first duty of the balloon is to find the best point for the front field where the supplies, etc., may be stacked, and for the newly placed commimi- cations of the fortifications. Further reports as to the conditions of the fort and its surroimdings as well as its guns are made, and lastly to obtain the tactical measures of the defenders. The reports gathered during the preparation will make the choosing of the place of attack easier. When the place for attacking is decided upon, a general observation ser- vice for the attacking front is started, and the balloons Digitized by Google 90 MILITARY OBSERVATION BALLOONS for artOIery range-finding and those for observing the results of the firing are put into service. Defense In GeneraL The defender usually has enough balloons to make a general observation from the f ort| which can be done at night, with good results. The bdloon can find out the important advance ground positions. Duties of the Kite Balloon. The balloon must obtain, for the fort commander, the data of the strength and arrangement of the besieging anny in the advance field. They must espy the camping place, the field trains and other used commimications as well as their activity, and lastly, the arrangement of the attacking ground and the tactical condition of the advance line. All these reports together with those obtained in other ways offer points for fimding the probable main direction of the attack. In addition the balloon must do observation duty for the artillery and also during the battle for the front ground of the fort. Uses of the Field Balloon Division in Time of War Field Balloon Division. The field balloon divisions are separate minor divisions, which are directly under the com- mand of the anny or the aimy corps. Field balloon di- visions cannot be separated and can only serve the balloon. Those divisions bring the necessary compressed hydrpgen in steel cylinders to the place of inflation. Using the Balloon. The balloon is used in field war, for tactical observation and only rarely for artillery pur- Digitized by Google IN ACTION 91 poses. The time for putting a balloon into service is to be considered carefully since an inflated balloon can follow a marching army only when the weather and land condi- tions are favorable; one inflation is good for only three or four days, and little inflating material can be kept in reserve. The inflation of a balloon is to be done only on important occasions. Divisions during Marches. The dividing of the balloon divisions is taken charge of by the general. When march- ing to battle the balloon division is formed into troop colmnns, if their employment is probable, and they are used as a vanguard to the leading division. The Reconnoissance. A thorough establishment by the balloon observer of the situation of the enemjr's and his own lines is the main f oimdation for a successful balloon observation. Otherwise, a mistaking of his own troops for those of the enemy cannot be avoided. Diuing the advance, the balloon observer must know the strength and marching routes of his own colmnns. During the attack he must be informed of the conditions of his own battle front, the strength of the flanks, and the preparedness of the reserves. He receives this information through the general staff chief or a general staff officer directly and in time; it is not to be given out inmiediately before ascen- sion, but should be received sooner, so that the observer may have time to study his field. Orders should not be given when the balloon is up, except when absolutely necessary, since the imparting of the instructions interrupts the observation. Uses of a Balloon during Battle. The general gives the command for ascension. He decides upon the ascension Digitized by Google 92 MILITARY OBSERVATION BALLOONS place and the time when the balloon is to be let up and when the carriers are to be sent The place of the corps supplies b to be made known to the commanders of the divisions. In counter attacks it will be of advantage to let the balloon ascend as soon as possible in order to obtain a definite idea of the strength and devdojanents of the enemy. During a stationary attack the balloon is to be used in that place from where the best \dew of the strength, position and actitiyy of the enemies' reserves can be obtained. During an attack the best opportimity for balloon maneuvering is given. The balloon can ascend from the shed near the place of attack and a telephone connection between the balloon and the general can be arranged to advantage. To report the advance of the beseiger, the grouping of the men for the attack, and lastly the attack against the flank and the advance of his own troop, com- pose the main duties of the observer. Inflation Place. The inflation place must be outside the gun range of the enemy's artillery and should be in a place sheltered from the wind and near the place of ascen- sion. Ascension Place. The selection of a place for the ascen- sion depends upon the tactical conditions and the bases which were selected for attacks against fortifications. During open warfare, ascension places cannot alwajrs be chosen away from the enemy's range. Commander of the Balloon Division. The commander of the balloon division must always be in communication with the superior commanders, and kept informed as to the aims of the generals and the results of the battle. Digitized by Google IN ACnON 93 During an attacking march he must march in the same Staff as the observer or be represented by an officer of the division. The division is led by the oldest team com- mander. The commander of the balloon division must, before the ascension, see that the observer understands the exact location, so that the observations will be taken from the right place. During the march the commander of the division watches for a satisfactory place for the ascension. Before advancing to the inflating position he hurries forward to decide upon the ascension ground and chooses, if possible, a hidden way for marching, giving the order in time, either by commands or signal. He sees, in case the groimd is not safe or in bad weather, that they are accompanied by an escort. In case he deems it feasible, he should ride toward them and lead them to the spot. The driving up for inflation should be done, whenever possible, under cover. After the division has arrived at the place of inflation, the comimander gives the commands necessary for putting the balloon into service. In case the balloon division must be in readiness shortly after arriving at the inflating ground, the team commanders must hurry to the commander of the division, who gives them the necessary directions and then orders the driving in of the division. Digitized by Google CHAPTER Vn Th0 Roles for Kxaminfng and Accepting the Cloth to be Used In the Manufacture of a Kite Balloon. The Care of Mate- rial and Its Repair Examination and Acx:eptance of Balloon Cloth The examination and acceptance of the balloon doth is divided as follows: 1. Examination of the plain cotton material before the dying and rubberization. 2. Examination of the rubberized material. The doth must be examined by commissioned officers of the aeronautical department, in the presence of the manufacturer or his representative, to see if it answers the necessary requirements. The doth from the various manufacturers is to be exam- ined in sections and a single piece as a testing piece must be chosen by the examining officer. It is of advantage to choose as a test piece one which feds as though it were of an inferior quality. The nmnber of samples to be tested per piece is to be left entirely to the judgment of the examining officers. Here it can be stated that when the material is put out by a reliable firm and in large quantities and when it seems to be of the same consistency in color, wdght, and touch, a smaller nmnber of testing pieces is needed than when the doth looks variable and seems to be of an imeven quali^* 94 Digitized by Google FABRIC 95 The unrubberized doth must be examined to see if it has the necessary number of warp and weft threads and if it has the required weight. If this is found to be so, it can be taken for granted, fairly accurately, that the cotton has the required strength and that the weave is of the necessary closeness. Then it is to be determined whether the doth has been prepared or if there are any defects in weaving. The plain cotton material can be washed, but not bleached or mangled. In obtaining the weight, the test pieces are to be weighed separately and the weight is figured. On account of the difficulty in obtaining an even con- sistency of the doth, a difference of 3 per cent over the given weight is allowed. Lighter material, if it possesses the given minimum strength, can be accepted. Three pieces are to be cut from the samples which are chosen for examination, 24 cm. long and 8 cm. wide in the weft and warp direction of the threads and then examined. The test pieces are to be taken from the ends of the pieces of doth as well as from the middle. The technical examina- tion starts with the tearing test of the dynamometer, in which the testing pieces 16 cm. long and 5 cm. wide have been stretched. Cloth whose ripping resistance is 5 per cent less one way than the other cannot be accepted. The counting of the fibers in the warp and weft is to be done on a surface i cm. square, and to facilitate this a thread counter can be used. If the difference between the warp and weft is three threads less one way than the other, it can be accepted; if more than that, it cannot. Digitized by Google 06 MILITARY OBSERVATION BALLOONS n the section of the unrubberized cotton doth is de- clared according to the test pieces to be as ordered, the single pieces are to be marked in the following way: The plain material is laid upon the table and every single piece is to be stamped with the stamp of the military aeronautical station with black oil colors on the extreme edge of both ends. When the material is being rubberized the stamp is not to be covered, as it is at the end which serves for sew- ing the material onto the machine rollers. Before the material is stamped it must be gone over to detect any breaks in the threads and weave knots. If sudi defects are numerous and the strength and closeness of the material seems to be lessened by it, the material in question is not to be stamped. DiuJng the stamping of the plain material a commis- sioned officer must be present. If the cutting and sewing of the balloon is not done in a military aeronautical station, but in a private establish- ment, the rubberized baUoon doth after it has been ex- amined and finished must be marked with a similar stamp if found to be up to the standard. But this is placed in the middle of the doth about 5 meters distant from the end. For stamping, only such dyes as are non-injurious to the doth are used. Test pieces of the various completed rubberized doths are to be tested by the various apparatus to see if they are gas proof and what their tearing resistance is. In case one or the other of the pieces is not up to the standard so that their use for the balloon seems impracti- cable, they must not be accepted. Digitized by Google FABRIC 97 It is of great importance to examine the cloth to see that the material is uniformly vulcanized and of a sufficient strength at both ends. This is done by dabbing a spot several times with benzine; if it becomes sticky, it has not been sufficiently vulcanized. A certain amoimt of experience and practice are neces- sary for judging the right grade of vulcanization. Repairing the Balloon Material This depends upon the way the material was handled in the first place during the time of use, second in the time before and during the storage. Use. For spreading out the envelope and net for infla- tion, the doth must not be pulled away harder than is absolutely necessary and witihout great tugging on the net. Stepping on the envelope must be avoided, and when it is necessary the men must take their shoes off or put felt coverings over them so as to lessen the damage. The doth of the envelope as well as the net is injured most by pulling it over the ground, because the material is rubbed off and becomes dirty very easily. If it should become wet, which is much worse, the doth must be deaned, as moisture is injurious. Car. The same holds true for the car, which must always be carried and not dragged over the ground, be- cause this would injure the wicker work as well as the ropes. The examining and repairing of the car ropes fastened in the wicker-work is very difficxilt. Sand Bags. Sand bags must never be filled for any longer time than is necessary, and they are to be kept dry« Digitized by Google 98 imJTARY OBSERVATION BALLOONS Tlie filled bags must always be carried and never dragged along the ground, and when they are taken out of the net or from a higher place, they are to be carefully pUced on the ground, but are never to be let fall. No more bags than are absolutely necessary should be hung in the net meshes, as that causes the weaker ropes to tear. Care must be taken that the bags are evenly distributed around the 'entire circumference of the net The men must seize the net evenly and at the same time all around. If one b a little bit slow an uneven distribu- tion of the net meshes over the envelope results, which puts a strain upon the net and even causes a dangerous stretching. The perfect f imctioning of the crow-feet lacings must be carefully seen to, as these keep the traction of the weights on the end lines the same on all meshes. The Mooring Rope. The mooring must never either during the laying out or the pulling in be pulled over stony, wet, or sandy ground, as this causes the zinc of the wire to rust. Dampness between the wires not only causes rust, but gradually destroys the insulation of the telephone wire. Dust is also to be avoided, as it causes a friction rub between the wires and cannot be gotten out, even by careful cleaning. When laying out the rope, dragging and twisting are to be avoided, as this might cause the rope, during the stretch^ ing, to tear at any place. The kinking of the rope or the single cord is danger, our, as the rope rubs oflf very quickly at such places, and the telephone connection is broken. When fastening the rope, the clamp must be fastened Digitized by Google FABRIC 99 In the traction direction of the rope, without any force, as the rope could rub through very easily on its edges. Should the rope be fastened by pulling it around some heavy or firm object, care must be taken that the slings are not twisted too severely and that they do not lie upon an edge. For this reason only large trees or round stakes of large diameter should be used. Rope Drums. Clamps. Pui^*^. In using rope drums, care is to be taken that t^ ^i ^ smoothly; the bearings are to be lightly fastened, and if necessary, oiled. The clamps for the telephone wire are to be kept free, and like the sliding contact, to be free from oil. Rope clamps are to be protected from dampness and dust during use, by placing wood or straw underneath, and dust or sand must never be used for increasing friction rubbing, but powdered rosm is to be sprinkled between the leather packings. The rope pulleys are to be treated the same way and are to be well oiled. They must be watched during use to prevent the rope from coming out of the socket and guiding arm, so that the splint or the friction nut of the roll axle will not become loose. Instruments. The instruments and apparatus which constitute the equipment of the car must be handled accord- ing to their purpose. Aneroids and telephone cases are most injured by dust and dampness, and must therefore never be packed in empty sand bags; they should never be disturbed unnecessarily. The instruments and apparatus must be taken apart by a mechanic only. The separate parts, such as springs, screws, etc., are never to be loosened or cleaned. Digitized by Google lOO MILITARY OBSERVATION BALLOONS Handling during Use and during Storage All the material is to be carefully examinedi and if necessary, repaired after its use. It must never be put away in an imperfect condition, but must be kept ready for use at any time. In case of long storage all separate parts are to be carefully cleaned and carefully arrai^ed. The Envelope. The envelope must be thoroughly aired by partial inflation of air, which is to be repeated several times. When all signs of gas have disappeared, the material is to be examined and any necessary repairs made. In case of poor light or dark rubberization, only electric lights are to be used. Care is to be taken that the envelope be not soiled by the chemicals which have escaped diuing the inflation from the gas apparatus. Such spots are not visible at first, but show up later by making the rubberization darker, and have an injiujous effect upon the envelope after it has been put away, not only at the spot, but tbe surroxmding doth and all such places as touch it. Such defects can be discovered through the difference in color or through testing with blue litmus paper, and must be neutralized with ammonia. In case decomposition has set in, it is best to cut the entire affected area out. A mere patch of repairing material must never be cemented over it. The same holds true for the net. Balloon Cloth. In case all the finished rubberized ma- terial is not to be used at one time, but stored for a longer time, it must be rolled up. The single rolls are to be packed in air-tight boxes in a vertical position and fire to be examined every three months. Digitized by Google FABRIC ..-•.; .::' \/:y:\\ ^01 It is not wise to have too much material prepared at the same time, as the slightest entrance of air hastens the oxida- tion and the corroding of the rubberization. In case it is necessary to place several envelopes on top of one another, the positions of these must be changed occasionally. Nets. The nets should be carefully dried and dusted, even washed, by taking up the single meshes slowly and carefully, and should be folded in the long way. All repairs should be made unmediately, or at least all injured places should be marked with a colored band to be repaired later. The net must be tied in various places by short cords and must be stretched the long way upon a table or a bench, or himg up on wooden pegs— never iron ones. Care is to be taken that no mice can reach it This holds for all the rope work. Rope Work. Heavier cords and ropes must be rubbed with tallow before storing. They are coiled, tied, and hung up on wooden pegs, or placed separately, but never on the bare ground. The Mooring Rope. The mooring ropes are to be rubbed dry, cleaned of all dust, and protected from rusting by greasing the upper surface slightly. Rusty spots in all metals are to be carefully removed, but care is to be taken that no petroleum or grease spots get between the cords into the insulation of the telephone wires. The mooring ropes are to be rolled up on their respective drums. Short pieces of rope (cross rope of the kite balloon) are hung up without rolling. The tail contact must be taken off the rope drum and the brake loosened. Valves. The valves, with the exception of those of the Digitized by Google llOJ ' • : ; ; {illLITAE^ OBSERVATION BALLOONS kite balloon, are to be taken out of the envelope for clean- ing, and after the spiral springs have been removed, they are to be hung up so that the rubber packing is free and so that the valve disk cannot lose its shape. Rubber Articles. Articles made of rubber, as washers, packing hose, etc., are best prevented from becoming hard and brittle by rubbing them off several times with ammonia water. They must never lie next to metal, because this is injured by the sulphiu: composition of the rubber. The Para rubber fluid can be stored only in sealed tin boxes. Conditions in the Storing Depot. The storing depot must be airy and dry, and if possible, free from dust It is also important that the temperature should always be the same, as the rubberization of the material is injured by changing temperatures. The windows of the depot are to be painted yellow, or to be draped with yellow doth. The varnished material is much more susceptible to changes of temperature. If the temperature is over 30^ C. the varnish becomes sticky, while below zero it becomes brittle and cracks. If the balloon doth becomes stiff and cold, it indicates either poor vulcanization of the rubber, or that the envdope has absorbed moisture which has frozen. Before it b spread out or used, it must be thawed until the doth is again pUable. The stored balloon material is to be aired every month in favorable weather. Digitized by Google CHAPTER Vra Materials Used The cotton material is smoothly and closely woven, of a linen consistencyj which is made of strong thread in warp and weft, both threads being of the same strength. The smooth upper layer insures even wearing and long endurance; the closeness of the weaving makes it gas tight by use of a small amount of impreguatmg material, be it rubber or varnish. The weight of the plain material is based upon the quality and the weight of the impregnating material , especially in varnished envelopes, so that the weight of the finished envelope cloth governs its strength* The firmness of the material in both directions is of prime importance^ Double diagonal-ply rubber cloth is difiicult to tear, while a single-ply cloth tears easily. By constructing the envelope in the proper way the length of a tear can be held at a minimum. Strength of the Plain Material, In examining samples of material, a section is taken and tested in the foDowing ways: A drawn thread is examined tmder the microscope to determine its fiber. Cotton fibers are easily distin* guished from the others. The fact that they are sub- stitutes is of less importance than tiiat of quality and tiiat 103 Digitized by Google 104 MILITARY OBSERVATION BALLOONS so-called ** dead threads ^' exist, as these have very little strength. With the naked eye one can judge the strength by the length of the fiber in the unraveled thread; it can be further tested by weighing it in grams upon a feather or threadscale. This test can be made only in a laboratory and hence is seldom used. The other examinations are more easily made and are quite satisfactory. In order to determine the strength the cloth is placed under a magnifying apparatus (thread counter), the dropped threads per i cm. in both directions giving the imiformity of the weaving. Loosely woven doth often appears firm even if held against the light, because it has been prepared with starch or rubber, which covers the space between the threads. After this has been removed its open texture will be evident By weighing the material of a certain area the weight per square meter can easily be obtained. Fiuther tests serve to determine the strength of the doth against tearing. For this purpose dynamometers are used, which are constructed after the following prindple: The fabric, cord, or crushed material is fastened into two slides which are secured by means of clamps to a horizontal or vertical frame. One slide is connected with a dynamometer spring, while the other can be set in motion along a screw which is turned by a hand crank. When the slide travels along the screw it causes the spring which is connected to the other slide to stretch; this operates the hand of the dial which indicates the strength of the doth. Digitized by Google VARIOUS MATERIALS 105 When the strip tears, the spring returns to its original position and the pointer remains at its highest point. In order to compare the strength of different materials, the testing pieces must be cut Uie same size and shape. The pieces are cut 5 cm. wide; as the distance from the side of one clamp to the other is 16 cm., as much material as is required for fastening is allowed in the length, and that is to be marked by pencil marks. The pieces are cut a trifle larger in order to allow for the pulling out of the super- numerary threads and so finally to obtain the necessary width. It can be done more accurately by coimting out the threads of a similar width. The fastening of the strip must be done very carefully, so that the damp stands perpendicularly to the length of the fibers. Then the strip is stretched lightly, on both sides, into the clamps, which grip the strip outside the pencil mark. One damp is then tightened by turning the screw. The strip is then pulled out from the other, by lightly rubbing, imtil the pencil mark is visible. Testing several times the clamps will be placed the correct distance apart and parallel to the pencil marks. The balloon materials used for rubberized balloons show the following strengths: in warp, about 40 kg., in weft, about 37 kg., in warp, about 25 kg., in weft, about 20 kg. Thus the strengths of these materials are 800 kg., 740 kg., 500 kg., and 400 kg., respectively. Numerous mathematical calculations can be made to Digitized by Google 106 MILITARY OBSERVATION BALLOONS ascertain the fiimness. An expansion of 5 to 15 per cent of the length is to be expected before it tears. The moment of tearing must take place at all points of the cross- section at the same time; if the thread pulls through in steps it indicates a poor weave. Poor material does not tear off by fits and starts, but by gradually falling apart, when the fiber of the threads pulls out and the tear is fringed. A good tear is straight and short, those in the direction of the warp being always of greater signifiance than those in the weft Minor distinctions are of no account in the value of the goods. All materials ior rubberized or varnished envelopes are used in an imbleached, washed condition. Bleached mate- rials are not used, less because of the difficulty in detecting faults hidden by the bleaching process than because rub- berizing dyes them or they become dark colored when varnished. Dyes. The rubberized envelope is the only one which is to be dyed in double-plied material. The outer layer only is to be dyed. The dyes give the goods a unifonn color and lessen the chemical influence of the sun's rays upon the gutta- percha. £}q)erience has shown that the chemical conditions of the atmosphere and the injurious qualities of the carrying gas do more damage than the rays of the sun, but cannot be lessened by any dye. To lessen the force of the chemi- cal light rays and the heat rays we can use light-colored material, between yellow-green and yellow-red. Until now, the material has been dyed either with a Digitized by Google VARIOUS MATERIALS 107 heavy mineral dye — chrome yellow — or with aniline yellow. The first can be easily recognized by the trace of the redt the latter by the green. The chrome yellow has the advantage of having greater durability. It prevents the drawing of water through the material and hinders, if only a little, the vulcanizing of the rubber, and becomes then on account of its sxilphide of lead composition, a dark green or gray. The aniline dye is not permanent, causes the material to draw water, rather than preventing it, and after a short time bleaches out entirely in the sim. The black rubberization takes both kinds of dye well, the white rubberization only the aniline dye without changing color. This changing color is an excellent means of control for a perfect vulcanization of white rubber. For these reasons the aniline dyes are preferred. After the above-named purposes of the dyes are con- sidered, it is of no consequence if the material is light yellow or gray, as its appearance is no worse than the yellow dyes, which soon become dirty. The aniline dyes are to be preferred to the chrome yellow. They offer the greatest advantage and last longer. Preparation of the Rubberized Balloon Clots and Envelopes Rubberization of the Cloth. The material decided upon, and which has been previously dyed, is rubberized in the factory with a thin coating of gutta percha. This is done by a calender, the material being placed between the rolls and a stiff composition of Para rubber and naphtha then applied by spreaders, the latter being so placed Digitized by Google 106 MILITARY OBSERVATION BALLOONS against each other that a very thin coating of gutta percha remains on the material; after the spreader has passed over it| it is dried on a long table kept wann by steam. These applications are repeated imtil the desired thick* ness of the rubberization is obtained. Eadi time the spreaders must be placed further apart. It is best to go over it several times, so as to obtain an even distribution of the rubber. If one-ply material is to be rubberized, the entire gutta percha is to be applied upon it, but if double-plied material is used, half of the gutta percha is placed on one ply, and the remainder on the other ply. In order to obtain one united piece of material the two pieces are put with the rubberized side toward the inside of the calender roller, and through pressure the rubberized sides adhere and the material is flattened out on both sides. The manufactiure of double diagonal cloth is more dif- ficult, as most of it has to be done by hand. For this the material, not dyed on the inner side, is cut along the length in rhomboidal pieces with a slope of 45^ and along the width of the upper material. These are then placed and stuck on by hand to the rubberized side of the upper material of the outer cloth, so that the whole area is covered evenly with pieces of the inner material, which must overlap a little and lie exactly parallel to each other. The double cloth is then run through a calender to make it smooth and to insure a perfect imion. During this process the material is wound off by wooden rollers and then woimd up again in order to prevent folds Digitized by Google VARIOUS MATERIALS 109 or a smearing of the material. The material is always made in bolts of about 30 meters length. Vulcanizing the Rubberization. All rubberized doth, be it single or double plied (with the excqption of the single ply used for repairing or gas-proof piuposes), must go through the process of vulcanization. The vulcanization makes the applied rubber — ^which in its present condition is still elastic, therefore soft, plastic and not resistant, and which would become hard, brittle, and lose its consistency, when exposed to the air — ^less susceptible to injury through atmosphere or temperature. For this piupose fine powdered sulphur is thoroughly mixed with the solution of Para rubber and naphtha and this mixture is then run over the cloth. The vulcanizing process follows: The rubber is kept under heavy pressure and at a temperature of about 140® C. The sticky and plastic mixture, in which the sulphur can easily be distinguished, is changed into an even, trans- parent, homy mass, which is very elastic and resistant, is air and water proof, and resistant to mild acids. The vulcanized rubber does not become brittle in the cold and has a longer resistance to the oxidizing influence of the atmosphere. The vulcanization of rubberized material on rolls takes longer and is more difficult than that of massive objects of rubber. The heat penetrates slowly and unevenly into the bolt and heavy pressure cannot be obtained. Such material is best vulcanized in a dosed kettle, in which there is a steam pressure of four to five atmospheres for several hours and at the same time a temperature of about 140^ C. Previous to this, the material is rolled Digitized by Google 110 MILITARY OBSERVATION BALLOONS upon hollow metal rollers and wound around with waste material imtil the latter causes pressure upon the bolt of materiaL It is impossible to obtain a perfectly even material, as the inner layers of the bolt are not so completely vul- canized as the outer. This is noticeable later on the single panels of the completed envelope, which wear out quicker. Some of the bolts of material made at the same time are imperfect, but that cannot be he^>ed, as there is no better method. Besides this system of vulcanizing, which is called vulcanizing by heat, there are several others. There is a cold vulcanization, which is used for the so-called patent rubber goods. For this the pure Para rubber (without sulphur) is combined with a fluid called chloride of sulphur, by means of steam, which gives an ineffective, evanescent sulphuri- zation of the rubber. Since this process must be followed by steaming, com- bined with a treatment by muriatic add, the material is weakened more or less and cannot be used for balloon cloth. Cold vulcanization of rubber (patent rubber) is much less serviceable and the upper surface becomes very brittle and hard when exposed to cold. The material vulcanized in that way must afterward be freed of the muriatic acid. Examination of the rubberized balloon cloth consists of : 1. The test of the weight of the rubber. 2. Examination of the vulcanization of the close layers. Digitized by Google VARIOUS MATERIALS 111 3. Strength of the material. 4. Gas tightness. The Weight of the Rubberization. In order to deter- mine the weight of the rubberization, one must first know the weight of the doth when dyed; after taking the weight of the material (in double-ply material the weight of the outer and inner layer) from the weight of the finished product, the remaining weight is that of rubber, which is then judged by the unit area. On account of the uneven distribution of the rubber on the entire length of the cloth, and on account of the small amount of rubber that is used, one must in order to obtain dose data weigh several pieces from the same bolt and then determine the result mathematically. In the rubber factories the necessary amoimt of rubber is weighed off and then run back and forth on the length of the cloth through the calender with the rolls a certain width apart until it has all been used. It sometimes happens that, on account of this, there is more rubber on one end than on the other. Small differences in weight are of no importance. For complete rubberization of cotton material 100 to 120 grams of rubber are required per square meter. For light, plain material the smaller quantity is suffident. For the double material the larger quantity is used on accoimt of the threads of doth crossing so much, and therefore lessening the strength of the rubberization. Cloth used for repairing and as gas-tight strips for the seams, which is usually used double on both sides of the envelope material, is suffidently rubberized by using 50 to 60 g. of rubber per sq. m. Digitized by Google 112 laLTTARY OBSERVATION BALLOONS The weight of the layer of rubber indicates its thick- ness; 100 g. of rubber per sq. m. give a layer o.i mm. in thickness. The weight cannot be judged by simply meastuing the thickness, or vice versa, because diuing the application the rubber is pressed into the space between the threads of the weaving, so that it is not flat upon the gckxls, and would not have the same thickness on the cross threads as woxild be given by the calculation of the weight per sq. m. The weighing of the non-vulcanized rubber cloth is not a reliable method for determining the weight of the rubber. The result obtained this way is always higher than after the vulcanization, because then the superfluous sulphur is removed by the continuous effect of the heat. Examination of the Vulcanization. The vulcanized rubber is usually not soluble in the ordinary dissolving solution; it simply swells more or less and after drying is unchanged. In articles made of patent rubber and in rubber that has not been vulcanized by the hot vulcaniza- tion the swelling is excessive. The more thorough the vulcanization the less the swelling. By soaking and moving the doth in a dissolving solu- tion the rubber of the imvulcanized doth will come off en- tirdy, and by allowing the solution to dry up it can easily be placed upon a slide and examined. If the rubber layer can be percdved by the eye (one- side rubberized plain goods) a magnifying glass will dis- tinguish to some extent, the free, meal-formed sulphur in the rubber of the vulcanized doth. Strength. The test for the strength of the rubberized Digitized by Google VARIOUS MATERIALS 113 balloon doth, is made by the tearing machine. For this, several testing pieces are to be examined in both directions, because there will be a greater difference than in the plain material. If the material is pulled through too closely placed spreaders, it is injured, as the fibers and the cross fibers are severely crushed. The cloth is sometimes burnt by the heat of the vul- canizing process and the surplus sulphur. This is in itself imavoidable, yet by careful manufacture the strength of the cloth is insignificantly lessened, especially in double cloth. The strength of straight double-ply cloth is almost equal to the sum of the two pieces in either thread direc- tion. In comparison, the strength of the diagonal double- ply doth is only the strength of the stronger of the two. Testing the Gas Tightness. For examining the im- perviousness of -the rubber layers, as also of all the mate- rial used to make the doth tight, for example, of varnished material, one can, as long as the mechanical resistance of the tightness is to be considered, use the following appa- ratus. The so-called (bursting) tearing apparatus. Fig. 28, consists of a small cylinder, dosed at the bottom, and a strong projecting rimmed vessel G, of a certain area, for example 100 sq. cm. over the opening. A stretching ring Rf is hammered on and is fastened to the opening by a screw damp Z, so that the piece of balloon cloth which is laid between is stretched over the vessel, and is shut off air tight. The doth can be tightened from the inside by a slowly increased air-pressure. Digitized by Google 114 MILITARY OBSERVATION BALLOONS For sending the required amount of pressure there is a hollowed three-way connection, (f, on the side of the cylinder, which can be fastened with a strong hose to a pressure pump or to a mixed hydrogen-filled gas tank and a manometer M. A gradual increased pressure inside the vessel can be obtained easily by being careful in opening of the tank valve. This pressure is read on the manometer, and then Fig. 28.— Test for Fabric the strength of the doth can be judged. The cloth, in contrast with the bursting machine, is strained in all direc- tions at once, because it is bulged up under the pressure. The stretching ring has a high ridge; one can pour water upon the doth, which shows rising air bubbles the moment the rubberization becomes loose. The dead pointer T on the manometer finally registers the pressure under which the doth gave way. It is not difficult to tell from these two pressure heights, and from the amoimt of the bulging of the material, in Digitized by Google VARIOUS MATERIALS 116 connection with the results of the tearing apparatus test, the ultimate expansion, when the material loses its strength and becomes useless. In these tests the pure mechanical density of the balloon fabric varies visibly upon examination, because of the trans- parency of the thick layer caused by the gas diffusion. From this standpoint there is no absolutely firm material, but there are some of a higher grade than rubber, for in- stance, varnish and goldbeaters' skin. Even without pressure in the balloon, which strains the envelope, the gas would escape through the envelope. The speed of the diffusion depends entirely upon the gas pressure, the nature of the gas, the thickness of the rubberization and the size of the balloon. In order to determine it, a simple apparatus. Fig. 29, is used, whose principles are as follows: If pure hydrogen is put into a gas-proof cylindrical vessel, whose cover is formed by a stretched piece of balloon doth of a certain area, the vessel being closed by a movable liquid cork in a manometer tube, the moving of the liquid cork will show conclusively that the gas escapes through the meshes of the doth. If the manometer is calibrated and graduated into volumes, it is possible in a certain length of time, through the gas escaping through the doth, reduced according to the area of the doth, to determine the firmness of the doth in a completed balloon. The amoimt of diffused gas so added should really, in order to determine the diffusion into the inner part of the balloon, be increased, after a certain physical rule, by an equivalent amount of air, when it is desired to compare Digitized by Google 116 MIUTARY OBSERVAtlON BALLOONS Fig. 39*— Test for Diffusioii, Digitized by Google VARIOUS MATERIALS 117 the amount of escaping gas to the carrying capacity of the balloon, but this in genend can be passed over on account of the small difference and because with mixed and illumi- nating gas it cannot be estimated easily. For comparing the different goods, the results from the observation of the changing volumes are sufficient. The apparatus consists of a brass cylinder Z, with a firm floor, a covering ring R, hammered upon its upper projecting rim of loo sq. cm. area, and two porous circular plates of clay P, of which one is placed in the opening of the cylinder and the other in the ring. The cloth is laid over the opening of the cylinder and after setting up and stretching the ring with the screw clamp Z to the vessel, making it gas tight, is pressed lightly between the two plates. This serves the purpose of preventing the change of volume of the shut-off gas in the vessel, when the doth gives way imder increasing inside or outside pressure. For keeping out disturbing influences of the changing temperature in the air of the testing space, the vessel is imder a large glass bell G, gas tight, which rests upon a glass plate and is fitted up with a glass plug 5/, so that only the manometer tube Rm is in the inner part of the bell. The tubes introducing and expelling the gas stand out from below the glass plate P and can be opened and closed as desired through the gas cocks h. The test is made as follows: After the cloth has been stretched out between the day plates and the ring, and the rim of the vessel has been slightly greased, a certain amoimt of fluid such as vaseline oil or glycerine is poured into the manometer tube. Digitized by Google 118 MILITARY OBSERVATION BALLOONS Then the bell is erected, but its plug must be taken out, so that air can pass in and out ea^y. From a hydrogen-gas apparatus the purest and dryest hydrogen is led through the inlet pipe into the vessel, and then let out by the discharging pipe, until the interior of the cylinder is filled with pure gas, idiereupon the gas cocks are turned off. The gas is turned off at a certain excess pressure, so that if the fluid in the manometer originally stood at the zero mark, it is pressed down somewhat more than half of the length of the scale, when the bell is dosed with the plug and the time is measured from the moment the fluid in the manometer moves from } cc below zero until it has reached } cc above o. From this time, the height of the diffused gas volume (z cc) and the area of the cloth being tested (loo sq. cm.), one can easily figure the escape of gas per sq. m. and per unit of time, for example per day or hour, and can com- pare the gas tightness with that of other materials. The vessel is to be refilled with fresh hydrogen several times during each measurement Examination of Varnished MateriaL The same rules for examining rubberized balloon doth apply to the examination of varnished goods. Construction of the Balloon Envelope out op the Rubberized Cloth Varnished goods cannot give such a strong resistance to the further tearing in injured places as the diagonal double-ply rubber goods, with gores set together out of Digitized by Google VARIOUS MATERIALS 119 small pieces, to limit the tear to the smallest space by a seam, which is veiy hard to tear. In general, to assure the security of the envelope against the sudden increasing internal gas pressure, the deams are to be so arranged during the construction of the balloon that they cross as little as possible. In a spherical-shaped envelope they all run either in parallel circles, or, what is still more serviceable, in merid* ians, whence the elasticity of the material in the direction of the seam, on account of its stiffness, is lessened; but it can at least be expanded to its full extent in the per- pendicular direction. In order partly to obtain this desideratum in varnished envelopes, in spite of the seams nmning in both directions, the small pieces are best put together like a chess board, so that only the vertical running seams come together in the meridional line, while those running in the direction of the parallel circle form small connecting lines. The wider the gores are set on the equator of the envel- ope the less the number of seams needed, which not only make the cutting and putting together easier, but lessens the weight of the envelope considerably. This is a much desired factor, because the rubberized material itself is heavy, and the seams, on account of having to be finished on both sides, add to its weight. Patterns and Cutting Out the Gores. The gores are marked on the cloth after a pattern, and are then cut out. The patterns are drawn upon heavy paper (also card- board) after any certain construction method, and after cutting, an allowance of 1.5 to 2.5 cm. for seams is made on one side. Digitized by Google 120 MILITARY OBSERVATION BALLOONS Along the length of both boundary lines of each gore marks are made at certain distances from the ends of the pattern. These are guiding marks for the purpose of prop- erly fitting together the different pieces of material, and preventing injurious stretching of the goods. The marks on the inner lines of the seam strips also form boundary lines for the gores when the patterns are to be marked on the doth. The width of the pattern in comparison to that of the goods must always be so much smaller that the first can be marked over on the q>read-out and evenly stretched material in such a way that the points of the ends are not in the middle of the material, but lie diagonally against the edges. In this way very much material is saved, as there is little waste, and the gores can overlap one another quite a distance. It must be mentioned that the various gores are drawn sloping in the same direction, so that a stretch- ing between the single parts of the envelope does not occur. The work on the rubberized envelope begins with the cutting of the various gores and other parts. Then the putting together of the envelope is begim. Putting the Envelope Together. For gluing together, a stiff solution of rubber is put on, evenly thin, with a brush, or better still with a spreader, over the sides of both pieces that are to come together. The two gores are spread over one another, the width of the seam strip of the lower projecting beyond the upper (as book-binders do when they paint over several pieces of paper) so that one can cover at the same time the upper surface of Digitized by Google VARIOUS MATERIALS 121 the gore and the under surface of the other with one stroke. After the rubber is dry, the two gores are pressed to- gether. Care should be taken to stay within the given boundary marks. By going over the surface several times with an iron roller made for this purpose, a secure union is obtained. It depends on drciunstances whether one sews up the seams — two parallel quilting seams — ^after the gluing each time, or waits until a larger number of gores have been glued together and sews them at one time. This is decided by convenience and the condition of the sewing machine, whose arm's length and height allow only a certain amoimt of goods to go through at a time. The final seam of the envelope is the most dij£cult, but since the slit on the ripping panel is still open, the work can with care be done quickly. The best arrangement for gaining time is ta glue and sew as well as finish the seams at the same time. The gores are glued together and sewed first in pairs, then in fours, in eights, etc. The gores are to be set together on the equator and must have each half of the balloon finished separately when the equator seam is finally sewed on. For this the two halves axe placed on one another, glued and sewed, for such a length that it is still possible to pull the strip through the sewing machine. The final seam can be sewed only through the ripping panel. The slit of the ripping panel is dosed by turning the edges around, brought to the outside, not inside, and stretched for i cm., and is reinforced at both ends by Digitized by Google ta MItrrARY OBS£RVATIC»f BALLOONS m strong piece glued and sewed on to prevent tearing. The seams of the rq^ing i>anel are not to be finished, but if it is done, then only from the outside. Close stitching should not be used on all seams, as they weaken the doth very much. A stitch 2 mm. long is very serviceable. For completing the work on the envel<^, reinforcements are usually glued on the upper third of the circular surface around the valve opening, and are cut out according to the gore pattern, and extend ahnost half a gore breadth from the valve. They reinforce that part of the envelope which has the greatest strain from the gas and prevent the net knots from rubbing through. Finally the opening for the valve is reinforced with one or more layers of double doth and then the hole for the valve is cut The appendix opening should be as wide as one-tenth of the diameter of the balloon. Small openings are dai^er- ous and too large ones are of disadvantage on account of the escape of gas and polluting; but this can easily be remedied by longer appendix bags. In order to prevent the rain from dr<^^)ing into the car, a rain strip is placed on the lower part of the bag. It is made wide enough to shed rain outside the car. The wooden iq)pendix is an important factor in free balloons in attaining easy inflations, besides reinforcing the appendix opening of the envelope. It is fitted with rings to which appendix ropes can be attached. The appendix ring is set in from the inside and is covered with leather on the outside and studded with nails. Since it forms a handle during the handling of the work, it is Digitized by Google VARIOUS MATERIALS 123 necessary to ghie a double piece 1.5 to 2 meteis around the iq)pendix opening. For tightening strips as well as for reinforcement unvulcanized doth is xised more than vulcanized, as it adheres better. Para rubber is never spread upon the plain rubberized clothy be this vulcanized or not, as it swells and is easily loosened from the material, and is made entirely soluble by the cementing material. Since such material is always to be cemented upon the cloth side of the balloon, the Para rubber is spread only on that side. Gas-proof strips are required in such numbers that it is necessary to cut them out upon a turning lathe from a whole bolt of cloth rolled up on wooden rollers. For this the knife is dipped in water. The width of the strips is governed by the width of the seams. Examination of fht Completed Envelope. Every newly constructed envelope must be thoroughly examined before it is used. The ripping panel is closed for this purpose and the valve is set in. The envelope is inflated with air, whereby all big mistakes in the construction and expansbn are easily seen. After the outside examination, it must be examined from the inside to observe the consistency of the cloth and the rubberization as well as to discover any mechanical injuries (stitches, cuts, friction rubbing and oil spots) and the tightness of the seams. For night work or when the envelope is rubberized with dark rubber, or in case a light is needed, no light but an electric one is to be used. In hangars these are the only lamps permitted. As soon as the edges of the ripping panel sUts are injured Digitized by Google 124 MILITARY OBSERVATION BALLOONS through use, there is danger of a difficult loosening of the strip. The rij^ing arrangements must then be placed upon another gore and the former one treated as though a large tear. When this is done, the changing of the mark of the ripping panel to the proper gore of the envelope must not be forgotten. Digitized by Google CHAPTER IX The Spherical Captive Balloon. Equipment; Inflation, Anchor- ing, Ascension Envelope. The spherical balloon (Plate n,) consists of the envelope ff, the net N, the coupling ring R, and the car K. The envelope is made of yellow rubberized cotton diagonal cloth and is put together in meridional gores. The upper part is called the upper cap and the lower part is called the lower cap. Added to this is the appendix F, together with the appendix ring Ar and the rain strip Rsi. The envelope is reinforced at the top of the t^per cap and the top of the appendix by doubling the material At the top of the balloon a valve opening is cut. The line of the greatest dramxference peipendicular to the seams is called the Equator, Equ. The Upper Valve. The upper valve doses the valve opening so that it is gas tight and consists of the fdlowing (Figs. 31, 3a): X. Upper valve ring Fr a. 2. Lower valve ring Vri. 3. Valve disk with valve cord L. 4. Spring F and wing nut S. 5. The two paddng riiigs made of rubber. 6. The three guide rods PsL 125 Digitized by Google 126 MILITARY OBSERVATION BALLOONS Fig. 30. — Spherical Balloon. Digitized by VjOOQIC Digitized by' 126 Digitized by Google Digitized by Google Digitized by Google SPHERICAL CAPTIVE BALLOONS 127 Fig. 31. — Upper Valve, Sf^rical Balloon. Digitized by Google 128 MILITARY OBSERVATION BALLOONS The upper valve ring is made of bronze and consists of a valve ring Ff2, fitted with the screw holes, and the ho(^ frame B for the valve spring F. The valve disk is a circular rim made of wood whose opening is covered with rubberized material. The gas- tight compartment is formed by means of the gutta percha Fro. 32. — Ui^)er Valve, Spherical Balloon. washer Dr^ having six valve springs pressed against the packing ring of the upper ring. On the lower side of the valve disk three eyelets are fastened. A yellow-black valve rope is fastened into a loop which passes through the eyelet. The lower valve disk is made of bronze and is tightened by means of the thumb- screw toward the upper valve disk. The material of the balloon St is placed between these two valve disks and held by means of thumbscrews. The Digitized by Google SPHERICAL CAFnVE BALLOONS 129 valve disks are made gas proof by means of packing rings. The lower valve disk has at its under side two eyelets A for the fastening of a coil with the loose loop 2?, to which is fastened the ripping lock bolt Every valve has six Fig. 33. — ^Lower Valve, Spherical Balloon. q^rings, one end of which is fastened to the eye of the snap, the other into one of the screw bolts of the valve disk. They fasten the gutta percha washer of the valve disk to the packing ring of the upper valve ring. To limit the motion of the valve, and to direct the valve disk while it is open, there are three guiding rods Fsl^ Digitized by Google 130 MiuTAJtY observahdk balloons o-b. Fw. 34.— Lower Valve, Spherical BallooiL Digitized by Google SPBSaOCAL CAPnV£ BALLOONS 131 secured t^ meaos ol nuts. These guiding rods lead into the straps £, and pass through the wooden part at the vahe disk hdding the eyelets fc^ the valve rope. Lower Valve. The lower valve is also a disk valve. (Figs. 33, 34.) It is made up of the valve ring Vfy the valve disk T, the rubber pacing ring H, six valve springs /, three guide rods s, three ^ring hoops and three guide straps i, and the lower valve rope /. The lower valve opens automaticaUy wl^n the gas pressure in the baUoon has reached a certain height. It can be opened from the car by pulling on the valve rope. The fasteiing of the low^ valve m the aj^ndix is Fio. 55.— Fastening of Lower Valve. obtained by means of a valve belt G (Fig. 35), together with the exchange mechanism and its cord. In order to fasten the lower valve in the appendix it is pushed from underneath. The rippbg rope and valve rope are to be led out between the appendix and the valve, so that these lines will lie upon the disk valve. On tap of this the valve is to be fastened from the outside by means of the valve belt in such a way that the rope lies upon the easily bound nut at the circumference of the valve. The valve belt must be taut and the clamp must be put on in such a manner that in order to open it is only necessary to turn it down. Digitized by Google 132 MILITARY OBSERVATION BALLOONS The exchange rope, which leads to the basket, is fastened onto this damp. Several loops must be placed on the hook from underneath, between the belt and material, so that the hook will not open when pulled accidentally. By pulling on the exchange rope, the lower valve is opened and falls out of the appendix. In order that the valve should not fall into the car, it is fastened by means of three cords to the eyelet of the ring in the ai^ndix ring. The various parts of the valve are to be marked so as to make assembling easier. The Ripping Arrangement The ripping arrangement serves to deflate the balloon rapidly as an aid in landing, and consists of The ripping seam. The ripping panel. The ripping line Ri and latch RK (Fig. 30). The ripping seam is a balloon gore which has a meridio- nal slit of scant 3 cm., which reaches from the upper third of the envelope to the equator. The edges are seamed. The small slit-like opening is made gas tight by means of the glued-on ripping strip. The ripping strip is made of balloon cloth about 20 to 25 cm. wide. At the upper end of it there is a wooden toggle for the fastening of the rq)ping line. This serves for pulling off the ripping strip. The ripping line is a strong red band, which leads into i}fid car and has a ripping lock bolt near its upper extremity. This ripping lock bolt prevents the too early opening of the ripping seam. On the lower cap of every free balloon the ripping seam must be marked with a black arrow. Digitized by Google SPHERICAL CAPTIVE BALLOONS 133 The Appendix Ring. The appendix ring is made of wood and strengthens the upper part of fiie appendix. On its outer side there are several grooves for the fastening of the appendix ropes. Inside tiiere are three grooves for fastening of the lower valve. The appendix ropes are fastened in the car and serve the purpose of stopping the lower cap from swinging when the balloon is not completely inflated. The other ropes are carefully secured in order to prevent the lower valve from being pulled out of the appendix. In a strong wind the appendix rope should not be pulled too tightly, as this would cause a serious swinging of the car and hinder observation. The Net. The net connects the car to the envelope and serves as a fastening for the mooring rope onto the balloon. It is knotted together out of ramie-cord, and consists of the supporting net and the holding net. The supporting net or short net is made of horizontal rows of rhomboidal mesh, which end as single lines on the bottom. At the top it ends in a net ring which is fastened into the eyelet of the upper disk valve by means of net straps. The net is divided into three rows of lacings, the small, the medium, and the large. Onto the larger ones the end lines are fastened. They serve to connect the net with the ring and have at thdj; free ends eyelets for taking up the toggle of the ring. The holding net starts at about the middle third of the balloon and consists of three rows of lacings which end in twelve holding lines. They are distinguished from the end lines by a metal thimble at their ends, Digitized by Google tat imiTABT OBSERVATION BMUOmS throui^ wliidi die running KneyWliicli is ^ meters kng, is pulled The mooring ring on the balloon consists of a steel pipe^ covered with ramie cord» and having toggles at the top axid bottom. On the upper side there are twelve toggles ics fastening end Unes^ on Ite lower side four toggles for the car connection. There are four rope loops also fastened to the ring which connect to an inm ring. To this ring the Topc damp of the mocning cable is fastened. The car is larger and held more securely than that (rf the kite balloon and is fastened to the ring by means erf the car ropes. Plate II, Fig. 3a The short ropes lead from the narrower sides and the long ropes from the longer sides. These ropes, O, end in the leather-covored rope loops Na I to No. 4. The sugyCTSJon of the car by means erf the car rq>es is linear. The foiu: toggles are arranged in two (^yposite diametral groiq)6 of two tc^ggles each and serve for fastening the four car rq>es. The car is fastened onto ring R; the nq>es ol the narrower sides of the car are fastened diiectly, and those of the longer sides crossing each other into the opposite diametrical car toggle of the ring. The equipment of the car is the same as that of the kite baUoon except for the addition of the mooring ring. Inflation of a Spherical Captive Balloon The balkxm is placed cm the rectangular ground doth so that the valve inlet is in the middle and the appendix ring end is turned toward the gas apparatus. It is important to watch that neither the upper nor the Digitized by Google SPHERICAL CAPTIVE BALLOONS 1S5 lower part of the material wrinkles, and that no wrinkles shut Q& the openmg of the appendix. To prevent this the material must be laid in folds over the appendix ring so that one can see through the appendix into the envelope. Then a petty oflBicer seizes the ripping and safety valve ropes, which have leather-covered ends, and leads them from the valve opening out through the balloon about 2 meters outside the appendix. Then he places the ripping rope in coils from the appendix ring in proximity to the valve c^>ening, and fastens its upper end with ramie cord onto the toggle of the ripjung panel, allowing the ring of the rij^ing cord to lie in the valve opening of the expanded envelope. Now the valve rope is laid in coils from the appendix ring to the valve opening. Therefore it is of great importance that the coils of both lopes should lie separately so as to prevent them from becoming en- tangled dining the inflation. The Vahre. The setting in of the upper valve now follows. It is separated from the lower valve ring by imscrewing and loosening the wing nuts and the valve springs of the upper valve ring and the latch, which is fastened to it by means of ropes. This latch is also fastened onto the ring in the ripping line, so that the snap of the valve rope is snapped onto the rope loop of the valve disk. The valve ring and the valve disk with the rubber washer are led upward to the valve opening of the envelope, and the materials in which holes have been cut are placed over the screw bolt of the valve ring, whence the upper valve ring is connected with the lower valve ring by means of a butterfly screw; it is necessary to avdd catching material between the two valve rings. Digitized by Google 136 ' MIUTARY OBSERVATION BALLOONS The Net One petty officer and twelve men of the balloon squad place the net so that the net ring endrdes the valve. Then the men seize the end lines and q>read the net; the officer stationed at the valve takes the net ring in his left hand and with his right seizes the upper net meshes as far up as the large crow-foot lacings, pushes the net over his head and has the men q[>read the end lines around the balloon, being careful that they are equal distances aroimd the balloon. He now shoves the net ring over the valve and fastens it by means of a rope (net- fastening rope) which is fastened onto the upper valve ring. Care is necessary that the net meshes are evenly distributed between the ropes. Now the command of *' lift the net " is given. The end lines are coiled and taken in the left hand upon the command of the petty officer of *' Large, Medium, Small, Crow-foot lacings." The large, medium and small lacings are seized separately at the rings by the right hand and placed in the left. Upon the further command of " One (two) meshes/' the others are placed in like manner. Upon the command of '' Halt " that part of the net which is in the left hand is pushed under the balloon and the holding line is coiled and placed upon it, then the petty officer in charge sees that a full sand bag is himg in every third mesh and that the point of the hook is turned away from the balloon. The Inflating Hose. The inflating hose is coimected gas tight with the appendix of the balloon by means of a tin pipe and then the balloon is ready for inflating. Inflation. Diuing the inflation, care must be taken that Digitized by Google SPHERICAL CAPTIVE BALLOONS 137 there are no folds in the cloth, and that the net is not pushed through uneven distribution. The folds of the doth can be evened out by means of pulling and shaking the doth in the vicinity. To prevent the net from being pushed crooked, it is necessary to see that the gas is evenly distributed and that the sand bags are hung in a mesh row so that these cause an even amount of tension. The Lower Valve. After the inflation the lower valve is set in. It is next fastened to the corresponding grooves of the appendix ring by means of ramie cords; then it is pushed upward by the springs to the middle of the i^pendix after the valve and ripping ropes have been laid in coils upon the valve disk. Then the elastic band with the point of the hook of the lock is swung upward aroimd the valve from the outside, tautly stretched and dosed. A ramie rope lo meters long for loosening the band from the car is to be so fastened to the hook of the snap that several coils lie between the belt and the envelope to prevent an acddental loosening of the band lock. Then the ring is fastened onto the main line and three ascension ropes are fastened to it with a knot. The Site of Anchoring. The anchoring place should be out of the range of firing of the enemy and also out of their sight. It is best to seek a place sheltered from the wind. The best places are roomy hollows, quarries, imused high- WBySy and behind houses or groups of trees. On a flat unprotected plain, wagons or baggage can be placed upon the windward side after the earth is thrown up sunilar to a trench on that side in the direction of the wind. This is done in the shape of the balloon. The using of im- Digitized by Google 138 MHJTA&Y OBSERVATION BALLOONS piovned balloon sheds and wooden walls on the wind- ward side is of advantage. The [reparation of an anchoring place is the same as that of an inflating place. The balloon is to be anchored on the blanket in an uncoupled condition, fastened and we^ed down by sand bags. Th« Balloon Watch. A balloon watch must always be ready at the anchoring place, and have mallets, stakes, and ropes at hand. Under normal weather conditions and when the balloon is anchcMred near its storing place, the watch should con- sist of at least one conunander and three men. They must serve as a day and night guard. Under imfavorable weather conditions and when the balloon is far away from its storing place the nimiber of men is increased according to the judgment of the com- mander of the balloon squad, and an officer must stay with the balloon at all such times. The watch should see that the following points are observed: Under rising temperature and corresponding gas expan- sion the holding lines must be slackened. Under falling temperature the same lines must be tightened. It is best to dry the rope first in case it has beomie wet In anchoring during an increasing wind the anchorage is to be strengthened accordingly. Should the wind become so severe as to threaten to tear the balloon from the moor- ings, the officer at the balloon must, as a last resort, order the balloon to be cut open. This work is done by those men who are not at a given post Salutes are not given during this work^ but only after its completion. Digitized by Google SraERICAL CAPTIVE BALLOONS 139 .S^-T WtNb DiReCTION, Stakc Bau-oon Stake Line RiPFiNQ Rope Valve Rorb I^. 36.-«Aiic]ioriDg of the Spberical Balloon. Digitized by Google 140 MHITA&Y OBSERVATION BALLOONS The Anchoxino of a Spherical Balloon The anchoring of a ^herical balloon (Fig. 36) consists of the following steps: X. Laying out the mooring place by the car squad. 3. Stretching the rectangular blanket 3. TranqK>rting the uncoupled balloon onto the ground cloth, placing the rii^ing seam in the wind, weigh- ing down the balloon by means of sand bags, and fastening the holding line onto the stakes by No. I of the balloon squad. 4. Fastening the ripping and valve lines onto two stakes which are on the side of the ripping seam. 5. Depositing the car and its equipment. PreparationiC for Coupling. Upon the command of ''Ready for service" the crew step up.lto the balloon (Fig. 37). In order to divide the crew the commander gives the command of " To the balloon." Whereupon the crew march to their places at the balloon. The balloon is held by the crow-foot lacings of the net meshes with both hands. Then upon the command of the balloon officer in charge the anchorage is lifted by the Nos. i. The three pieces of lengthening rope for the tran^>ort of the balloon are pulled down under the supervising petty officers and are held by the Nos. 6 of the balloon squads. Ascension The Car Squad. When the place of ascension is reached, the car and its equipment is placed with the short side in the direction of the wind and the crew advances as shown hi Fig. 37, Digitized by Google SPHERICAL CAPTIVE BAIXOONS 141 Digitized by Google 142 MILITARY OBSERVATION BALLOQ!fS ^\ \9^ 29I lf« ■-~^WiNO DiivecrtOM -*— i-fvtooRiNQ Cable :=RlPP»INq PaNBI. Fig. 38.<— AscensioBy Spherical BallooiL Digitized by Google SPHERICAL CAPTIVE BALLOONS 143 Nos. 3 and 4 take the rope pulley and traction ropes out of the car and Nos. i and 6 lay the car ropes out on the ground and place them as shown in Fig. 38. Then those niunbers seize the long car ropes and ex- change them in such a way that No. i takes the one handed him by No. 6 and pulls it through his own car rope under the eyelet. These numbers then fix the eyelets of the long car ropes into the car comers nearest them. This is in order to prevent a mistake during the coupling. After the mooring cable has been fixed, No. 4 of the car squad takes the rope lock and places the end of the rope above the crossed car ropes which are over the car's rim. The Rope and Reserve Squad. The work of this squad is similar to that of the kite balloon. The Coupling. After the balloon has been placed over the car the officer in command orders the balloon placed in such a way that the ripping panel is over the side of the car toward the wind. Upon the command of " Small, medium, laige crow-foot lacings," the balloon is gradually lifted so that the lower part of it can be handled; the end lines are to be held during this operation. Upon the command of " Coupling," Nos. i and 6 seize the rope eyelets of the short car ropes, which are lying on the groimd, and fasten them intd Uie left toggle of the ring procured for them by the car rope toggle group. Then they seize the rope eyelet of the outer car ropes and connect them with the free right car rope toggle. No. 4 couples the rope lock, No. $ lays out the ascen- sion ropes. In a strong wind and in order to relieve the men, sand bags can be placed on the end lines. This is done upon the Digitized by Google 144 MILITARY OBSERVATION BALLOONS command ^^ On the end lines." Then the crew advances, lifting the balloon higher on the end lines toward the ring; when the balloon arrives at the ring the command of " Halt " is given. Upon the command of " On the ring " No. 2 goes to the ring in order to strengthen the car squad. Upon the command of " On the ascension ropes," No. i, then 3, 4, 5, 6, and 2 place themselves in two groups at one ascension rope. The ascension of the balloon is then permitted. Digitized by Google CHAPTER X The Free BaOoon Equipment Preparation for Ascension. The Ascension We may class any other balloon than the spherical as a free balloon. Its size is governed by the capacity of the gas bag, the weight it can carry, the amount of material, and the time required in construction. Rubber balloons which use hydrogen for inflating should have a voliune of at least 600 cu. m., while those carrying illuminating gas must have a filling capacity of 1000 to 1300 cu. m. The free balloon consists of an envelope, the valve, the ring, and the car. In constructing the envelope the same cotton gutta- percha-lined cloth is used as in the captive balloon; or it can be made of silk. The valve is constructed similarly to the upper valve of the kite balloon, except it is made lighter and bigger. The valve disk and the valve ring can also be made of wood. There is no lower valve in a free balloon. The Appendix Ring. The appendix ring is constructed like that of the captive balloon, and serves the purpose of keeping the appendix opening in place should the balloon fall, so that the functioning of the valve and ripping rope will not be impaired. By fastening the appendix rope to a 145 Digitized by VjOOQIC 146 MnJTARY OBSERVATION BALLOONS ding attached to the car it prevents the car from turning over completely when landing. The Net The net of the free balloon usually has only two rows of crow-foot lacings and twenty-four end lines. The holding net is not necesaaiy. In case of a scarcity of nets a belt with the end lines can be sewed onto the equator to take its place. In free balloons, on accoimt of their very light wdght, wooden rings are used. If these are not at hand, rings made of gas piping or iron rings can be used, whidi are covered with the same cordage covering so that the toggles cannot move out of place. The wooden rings are firm on account of a right-angle cross brace. Safety rope rings are placed in grooves at the upper and lower runs of the ring. The ring of the free balloon has twelve or twenty- four small toggles for the coupling of the end lines, and eight or twelve large toggles which are evenly distributed around the ring for the coupling of the car. For the fas- tening of the tow rope to the ring thare is a toggle. The Car. The car is similar to that of the spherical captive balloon, only does not have a lineal suq)ension, but is fastened to the ring by means of eight or twelve, and in large balloons, with more ropes ending in eyelets. The car ropes are woven into the car and the sides of the car are not pierced. Tbe Landing. The landing mechanism of a free balloon consists of the valve and ripping panel with the guide rope. The rif^xing seam is like that of the spherical captive balloons. In free balloons the ripping slit can be wider toward the equator, and is cut out in the shape of a very Digitized by Google F1USE BALLOONS 147 p<»&ted triangle, which affords a quick deflation of the balloon. The base of the triiangle must be smalls than the gores. The length of the guide rope is calculated on the basis that for each lo cu. m. capacity of the bdloon z meter of guide rope must be allowed. Mechanism. So that the ripping arrangement will be aure to work when landing, the rii^ing seam and guide rope must lie in the same meridian. The ring is to be placed on the running line, to bring the toggle for the guide rope under the ripping seam. For ordinary equipment there must be: One army blanket; One guide rope; Two podsets for maps, etc.; One aneroid of 8000 meters; (free baUoon ascension) One thermometer; One set of field maps; One piece of rope of 25 meters laigth; One clasp knife; Two bags of confetti; Five pieces of cord, i meter long; Two packages containing 10 paper flags each; Bags filled with sand according to the carrying capacity of the balloon. After the end of the guide rope is fastened to the rope hoop of the ring, it is so attached to the car that it can be quickly let out. For this purpose the guide line is fastened in loops inside the car, the last loop hanging ova* the side of the car. During the adjustment of these ropes, the car Digitized by Google 148 MILITARY OBSERVATION BALLOONS ropes of the side in question must be held up by one man, while another does the adjusting, so that no loop is placed over a car rope which would later prevent the letting out of the guide line. If there is not enough room for the sand bags inside the car, they must be placed on the outside. Preparations and the Ascension of a Free Balloon Inflation. The inflation of a free balloon is similar to that of a spherical balloon. In case it is desired that a high ascension be made directly from the ascension place, the balloon is to be inflated only to eight-tenths of its volume. After the necessary inflation the appendix is to be con- nected by giving a strong tug on the knotted connections. During the coupling of the ring to the balloon care must be taken that the mooring rq)e (toggle) which serves for fastening the guide rope is fastened in the meridional plane of the ripping panel. Attendance. Tlie attendance for the free balloon is similar to that of the spherical, the arrangement of the crew being according to Fig. 39. Ascension of a Free Balloon The ascension of a free balloon is similar to that of a kite balloon, and is as follows: 1. Placing the equipped car of the free balloon on the ascension place, so that the guide rope is in the wind. 2. Placing the balloon over the car so that the ripping panel is in the wind. Digitized by Google FREE BALLOONS 149 1221 M^] m R.P S.P K.P \a E/ n Y m i Looi»Ro^B — — HOLAINQI Re _ _ |.Bf^qfrHBNlNC| ROPB Fig. 39.-- Attendance for Free Balloon. Digitized by Google ISO MILITARY (ttSERVATlON BALLOONS 3. Coupling the car onto the ring and the occupancy of the car. 4. Changing of the crew from the crow-foot lacings to the car ropes. 5. Laying out and lifting the balloon. The activity of i to 4 is analogous to the spherical balloon, only in a free balloon the cars which are used have their car ropes of the same length, so that these do not cross. During the changing of the men from the running rope to the ring, more men are demanded as the size of the ring increases. The rest of the crew are commanded by the balloon officer in charge to be at 50 paces distance from the balloon in the direction the balloon is going. Upon the command, *^ Up on the car ropes/' ascension with the car cable takes place. This must be done very carefully and the balloon must not rise rapidly. The speed of the ascension is regulated by the men stationed at the running ropes and at the car rim. The weighing out serves the purpose of giving the balloon as little lifting power as possible. It is done in case of a moderate wind by taldng off the lengthening ropes. The withdrawing of the lengthening lines takes place on the conunand of " Let the lengthening line go." All the commands of the balloon officer during the weighing out of the free balloon must be obeyed punctu- ally by the car occupants. Li order to determine whether the balloon has any lifting power the men holding the car let it loose for a Digitized by Google FREE BALLOONS 151 moment upon the command of ** Loose '' and it is again seized and held fast upon the command of " Tight/' Dmjng the weighing out of the balloon, the car proceeds only until the balloon has the required lifting power, when, upon the command of " Open the appendix " the appendix is opened by a tug on the rope. The pilot sees by looking into the balloon (rubber valve band) if the ropes are free and reports to the officer in charge: " Ropes are clear." Then the balloon is let loose at the command of " Loose," while those numbers holding the car let go at the same time. During a strong wind, the free balloon is let loose with a measiured lifting power. This is done by taking off several of the sand bags after the balloon has been lifted. In a free plain and during a moderate wind the balloon can be let up with its guide rope laid out. The latter is then laid in coils upon the ground in the direc- tion of the flight. In order to prevent the balloon from being pulled along the ground in case of wind during the ascension, the balloon, swinging in the direction of the wind, is to be let loose only that moment in which the swaying stops with the wind, and when the swaying has been renewed against the wind. Should the balloon, upon the command of ^' Let go " start to drag, due to difficult or improper ascension, the men who are stationed there must hold the car. Digitized by Google Digitized by Google m^////m//^ f/y/////'//i///y/z//i/i££^/////y/zjyz///^//y//y/^^//M////y///////////yA, \ \ MILITARY BOOKS A Short Title List of Standard Books on Military Science of All Publishers D. VAN NOSTRAND COMPANY Headquarters for MILITARY BOOKS SINCE 1848 25 PARK PLACE NEW YORK >y^^//Ar//yy////z//y/7y7yzy/y/z//z^/yy////y/y/yzi^^^ Digitized by Google Digitized by Google STANDARD MILITARY BOOKS Detailed descriptions on request. AERONAUTICS BURLS, G. A. Aero Engines $3.00 DIXIE, A. E. Air Navigation for Flight Officers 4.00 DOMMETT, W. E. Aeroplanes and Airships 80 DUCHENE, COMMANDANT Flight Without Formulae 2.00 DUCHENE, COMMANDANT The Mechanics of the Aeroplane 2.00 EIFFEL, G, (translated by 7. C. HUNSACKER) Resistance of Air and Aviation . . . . 10.00 FAGE, A. The Aeroplane 2.00 GRAHAM-WHITE, C, and HARPER, H. Learning to Fly 70 GREENHILL, G. Dynamics of Mechanical Flight 2.00 HAYWARD, CHAS, B. Building and Flying an Aeroplane 1.00 JUDGE, A. W. Design of Aeroplanes 4.00 Digitized by Google KENNEDY, R. FljingMachinaB* Practice and Design • • . $2.00 KENNEDY, R, Aeroplane Construction 1.50 LANCHESTER, F. W. Flying Machines from an Engineering Standpoint 3.00 LANCHESTER, F. W. Aerial Flight, 2 vols. Vol. I —Aerodynamics 6.00 Vol. n— Aerodonetics 6.00 LANCHESTER, F, W. Aircraft in War 4.00 LOENING, G. C. IfiUtary Aeroplanes 476 MATTHEWS, R, B. Aviation Pocket Book for 1917 1.60 PAGE VICTOR W, Aviation Chart* Power Plant Troubles Bfade Easy .60 Aviation Engines; Design, Construction, Repair . 3.00 Glossary of Aviation Terms; English-French. Francais-Anglais . 1.00 PIERCE, R, M Dictionary of Aviation . . • 1.60 ROBSON, WILLIAM A. Aircraft in War and Peace .... 1.00 SPAIGHT, J. M. Aircraft in War 2.00 TALBOT F» A» Aeroplanes and Dirigibles of War 1.26 WIDMER, E, J. Military Observation Balloons 3.00 WOODHOUSE, H. Textbook of Military Aeronautics 6.00 ARTILLERY, COAST AND FIELD Gunnery and Explosives for Field Artillery Officers .40 HAMMOND, J. S. and OLMSTEAD D. Gunner's Handbook for Field Artillery ... .60 ^Manufacture of Artillery Ammunition . . . 6.00 Digitized by Google BAVARD, V, Blilitary Hygiene $6.00 KEEPER, F, R. Military Hygiene 1.50 LELEAN, P. S. Sanitation in War 2.00 MUNSON, LIEUT, COL. EDW. L. The Principles of Sanitary Tactics 2.00 MUNSON, E, L. Soldier's Foot and Military Shoe 1.36 STRAUB, PAUL F., Medical Service in Campaign 1.50 WOOD R, C» The Soldier's First Aid 60 WOODHULL, A. A, Military Hygiene for officers of the Line . . . 1 . 60 LANGUAGES Rapid-fire English-French-Oermanfor Soldiers . .26 COLEMAN and LA MESLEE Le Soldat Am^ricain en France , 60 CROSS, H. Soldier's Spoken French €0 GULLICHAN, W, M. Soldiers' English-French Conversation Book 30 MORTON, MAJOR C. G. English-Spanish Pocket Manual. Cloth . . . 1.00 MOSS, MAJOR JAS. A. Spanish for Soldiers . . 1 . 00 Oxford English and French Conversation Book for Army and Navy Men 26 PICARD, 7. Cortina French-English Military Manual . . . 2.00 PLUMON, E. Vade Mecum for the Use of Officers and Inter- preters in the Present Campaign (French and English Technical and Military Terms) ... .75 Digitized by Google WILKINS, COLEMAN and HUSE Tint Lassons in Spoken French for Men in Mil- itary Service $ .60 WILKINS, COLEMAN and PRESTON First Lessons in Spoken French for Doctors and Nurses 60 MACHINE GUNS AINSLIE, G. M. Handbook on Rifle and Hand Grenades . . . 1.26 Combined Infantry and Cayaby Drill Regulations for Machine Gun Companies for Automatic Ma- chine Rifle, CaUber .30 (Model 1909) 30 HATCHER, J. S., and others. Machine Guns 2.60 Operation and Tactical Use of the Lewis Automatic Machine Rifle eo LONGSTAFF AND A TTERIDGE The Book of the Machine Gun 3.60 McKEDLAR, K. B. Machine Gun Practice and Tactics 90 MERKATZ, F. V. New Methods of Machine Gun Fire 26 SOLANO, E. J. Machine Gun Training 1.00 MANUALS UNITED STATES ARMY Cavalry Drill Regulations 76 Field Service Regulations .76 Infantry Drill Regulations 60 Manual for Non-Commissioned Officers and Privates 60 Blanual of Military Courts Martial . 1.10 Manual of Interior Guard Duty 60 Small Arms Firing Manual 79 Rules of Land Warfare .76 Complete U. S. Infantry Guide (26 Government Manuals) 6 . 00 Digitized by Google Shrapnel and other Wajr Material $1.60 Coast Artillery Drill Regulations 1.00 Provisional Drill and Service Regulations for Field Artillery (Horse and Light) 1.26 Provisional Drill and Service Regulations for Field Artillery (6 Inch Howitzer), 1917 .... 1.26 BETHELL, H, A, Modem Ouns and Gunnery 6.00 BISHOP, H, c. Elements of Modem Field Artillery .... 1.60 BISHOP, H. G. Operation Orders, Field Artillery 1.00 CLOKE, H. E. Gunner's Examiner 1.60 DYER A B Handbook of Light Artillery 3.00 EISSLER, M. Modem High Explosives 4.00 GRUBER, E. L. Notes on 3-inch Gim Material 60 GUTTMAN, OSCAR The Manufacture of Explosives. 2 vols. . . . 11.00 INGALLS, J. M. Interior Ballistics 3 00 LISSAK, O. M. Ordnance and Gunnery 6.00 MacAUSTER, D. A. Field Gunnery 1.00 MARSHALL, A. Explosives. 2 vols 16.00 MORETTI, O. and DANFORD, R. M. Notes on Training Fiold Artillery Details . . . 2.00 OMMUNDSEN, H., and ROBINSON, E. H, Rifles and Ammunition 6.00 RUGGLES, C. L. Stresses in Wire Wrapped Guns and in Gun Carriages 3.00 SANFORD, P. G. Nitro-Explosives 4.00 SPAULDING, CAPT. OLIVER L. Notes on Field Artillery . 1,26 Digitized by Google WEAVER, E. M. Notes on BIUiUiT Explosives $3.00 WISE, T. C. Gunnery; an ElemenUry Treatise • • • • . 3.00 WORDEN, E. C. Nitro-cellulose Industry. 2 vols 10.00 FIELD ENGINEERING Engineer's Field Manual 1.25 ARMY SERVICE SCHOOLS Notes on Field Fortifications 50 BEACH, CAPT, WM. D. BSanual of Bfilitary Field Engineering. 9th Ed. Revised. Cloth 1.75 BOND, p. S. Engineer in War 1.50 FIEBEGER, G. J. Textbook of Field Fortifications 2.00 KENYON, R. E. Land and Coast Fortification 2.00 ROBINSON, ERNEST F. Bfilitury Preparedness and the Engineer . . . 1.50 SOLANO, E. J. Field Entrenchments ; Spadework for Rifiemen . 1 . 00 VICKERS, L, Training for the Trenches 1.00 WALDRON, W. H. Elements of Trench Warfare 76 HYGIENE AND SANITATION Drill Regulations and Service Manual for Sanitary Troops * .75 Manual for the Medical Department, U. S. Army 1.10 ASHBURN, P. M, Elements of Military Hygiene ...... 1.50 HASTINGS, S. First Aid for the Trenches ..••••. 1.00 Digitized by Google SUTHERLAND, S. 7. The R«8erve OAcers Handbook. Cloth. . . $1.85 Limp Leather 1 .76 TURNER, C. fi^. and FULMER. J. J. Battle Fire Training 1.00 WALDKON, W, H, Company Administration 1 . 76 WELSHIMER, R. R. Primer for the Officer's Reserve Corps and Officers of Volimteers and the National Guard . . . . 1.00 PHYSICAL TRAINING Handbook of Phsrsical Training. 2 vols. (Eng- lish) Vol.1 60. Vol. n 60 BUTTS E L Manual Of Phsrsical DriU 1.26 GAREY, E. B. BSanual Of Phsrsical Drill 1.00 Manual of Physical Training, U. S. Armsr . -76 SCIENCE OF WAR ALTHAM, E. A. Principles of War. 2 vols 4.60 AZAN, P. . War of Positions 1.26 FLETCHER-VANE, FRANCIS The Principles Of MiUtary Art ...... 1.26 HENDERSON, COL. G. F. R. The Science of War 4.00 SARGENT, COL, H, H. Campaign of Santiago de Cuba. 3 vols. . . . 6.00 SARGENT, COL. H. H. Campaign of Marengo 1.60: SARGENT, COL, H, H. Napoleon Bonaparte's First Campaign . . . 1.60 Digitized by Google VON CAEMMERER Derelopment of Strategical Science during 19th Century . $3.00 VON CLAUSEWITZ, GEN. CARL. On War. 3 vols 7.50 VON DER GOLTZ, LIEUT.-GEN. ^ The Conduct of War 2.00 SIGNALLING Manual of Electric Instruments and Telephone for the Signal Corps ICO Drill Regulations for Field Company of the Signal Corps 76 JOLY, J. S3mchronous Signalling in Navigation 76 PALEN, M. A. Lessons in Visual Signalling 60 Signal Book, U. S. Army 35 STEVENS, E. J. Field Telephones for Army Use . . . . 1.00 ZENNECK, J. Wireless Telegraphy ^ . . . 4.00 TACTICS Tactics of Coast Defence 2.00 ARMY SERVICE SCHOOLS Studies in Minor Tactics 75 BALCK (COL,) Translated by Walter Kreuger Tactics Vol. I— Introduction and Formal Tactics cf In- fantry 3.00 Vol. II— Cavalry, Field and Heavy Artillery in Field Warfare 3.00 BOND, P. s., and Mcdonough, m. j. The Technique of Modem Tactics 2.65 BJORNSTAD, A, W. Small Problems for InfaiXtry 76 Digitized by Google ANDREWS, L. C, and others Fundamentals of Military Service $1 . 60 Bayonet Training Manual, Used by the British Forces 30 BOLLES, F. C. and others What a Soldier Should Know 1.00 FITSCHEN, H. Spade (Trench) Warfare. Trans, from German. .60 KILMER. W. C. and MACELROY, A. 7. The Cantonment Manual 1.00 DONOVAN, T. F. Home Guard Manual 60 GUILD AND TEST Militia Field Manual 1.00 HOLBROOK, L. R. Mess Officers' Assistant 1.00 HOLBROOK, L. R. Mess Sergeant's Handbook 1 . 00 LAWTON, MAJOR F, H, Extracts from U. S. Army Regulations .... 1 . 00 McARTHUR, J. C. What a Company Officer Must Know 2.00 MOSS, J. A, Army Paperwork 2.00 MOSS, MAJOR JAS. A. Infantry Drill Regulations (with annotations) .76 MOSS, MAJOR JAS. A, Non-conunissioned Officers' Manual .... 1 . 60 MOSS, MAJOR JAS A, Officers' Manual 2.60 MOSS, MAJOR JAS. A. Privates' Manual 1.00 ROBBINS, E. J, Uxiiversal Drill Manual 1.00 SELKIRK, W, O. Catechism of Manual of Guard Duty . . .60 SOLANO, E. J. Musketry 1.00 SPINELLI, MAJOR H, B, A Catechism of Court-Martial Duty 76 Digitized by Google TURNER, F. H. Infantry Drill Regiilations, Annotated . . . . $ .76 TUFBS, H., and POOLE, S. Manual of Bayonet Exercises and Musketry Fencing 60 WILLIAMS, A. B. Manual for Quartermasters 1.10 WILLIAMS, A. E, Company Supply Manual— Infantry 40 MILITARY TRAINING BROCKINGTON, W, A, Elements of Bfilitary Education 1.60 BADEN-POWELL, R. Quick Training for War 60 CAMPBELL, M. V. Rapid Training of Recruits 1.00 ELLIS, E. 0„ and GARY, E. B. The Plattsburg Manual. A Textbook for Military Training Camp 2.00 CAREY E. B. and ELLIS, O. O. The Junior Plattsburg Manual 1.60 MAKING, BRIG. GEN. Company Training 1.60 LAFFARGUE, ANDRE The Attack in Trench Warfare 60 MORRISON, JOHN F. Training Infantry 60 MOSS, JAS, A. Manual of Military Training 2.26 MOSS, JAS, A. Questions on Manual of Military Training .CO MOSS, JAS, A, Self -Helps for the Citizen-Soldier 2.26 PARKER, JOHN H. Trained Citizen-Soldiery 1.26 SOLANO, E. J, Drill and Field Training-Scouting 1.00 STACEY, C. Company Training 1.00 Digitized by Google Manual for Army Bakers $ .60 Manual for Army Cooks 76 BAKER, C. B, Transportation of Troops and Materiel . . . 1.60 BAKER, C. B. Handbook of Transportation by Rail and Com- mercial Vessels 1.00 BAKER, L O. Roads and Pavements 4.60 ESPANET, OCTAVE Notes on the Supply of an Army 1.60 HOLBROOK, L. R. Handling the Straight Army Ration .... 1.60 LAWTON, F. H. and others Field Quartermaster's Handbook 2.00 LAYRIZ, O. Mechanical Traction in War for Road Transport . 2 . 00 WEBB, W, L. Railroad Construction 4. 00 WIMPERIS, H. E, Principles of the Application of Power to Road Transport 1.60 MISCELLANEOUS Army and Navy Diary 60 BAKER, L O Masonry Construction 4.60 BAKER, M. N. Potable Water and Methods of Detecting Im- purities 60 BARNES, J, B. Letters of a Plattsburg Patriot (humorous) . . 1.00 BUNKLEY, J. W, Military and Naval Recognition Book .... 1.00 CAMERON, L. C. J. /?. Infantry Scouting 1.00 CARTER Horses, Saddles and Bridles 2.76 CLOKE, H. E. The Enlisted Specialist's Examiner 2.00 Digitized by Google DAVIS, G. B. The Elemeiits of Law $2.60 DAVIS, G. B. A TreatiBe on the Bfilitary Law of the United SUtes 7.00 DION, S. A. Tanks, Gas, Bombing, Liquid Fire 1.26 DUDLEY, E. S. Military Law and the Procedure of Courts llartial 2.60 FALLS, D. W. C. Army and Navy Information 1.00 FIEBEGER, G, J. Civil Engineering 6.00 FOSTER, H. A. Electrical Engineer's Pocket-book 6.00 FRYE, A. I. Civil Engineer's Pocket-book 6.00 GRUBER, E. L. Notes on 3-inch Gun Material 60 HENDERSON, D. Art of Reconnaissance 1.60 HOWE, G. Mathematics for the Practical Man . . . . 1.26 KENT, W. Mechimical Engineer's Pocket-book .... 6.00 LALLIER, E, V, Elementury Manual of the Steam Engine . . 2 . 00 LAWTON, F. W., and DEMPSEY, W, A. Quartermaster Administration 2.00 LODGE, O. J. Elementary Mechanics 1.60 MACQVARRIE, HECTOR How to Live at the I^ont 1.26 McKENNEY, H. J, Exercises for Ssrstematic Scout Instruction . 1 . 26 MARSHALL Elements of Hippology 1 . 60 MERRIMAN, M, Treatise on Hydraulics 4.00 Digitized by Google GRAY, ALONZO Cayftlry Tactics $1.00 GRIEPENKERL, MAJOR GENERAL Letters on Applied Tactics 2.00 HANNA, M. B. Tactical Principles and Problems 2.60 HOENIG, FRITZ Inquiries into the Tactics of the Future . . . 2.00 INGALL, J, M, Handbook of Problems in Direct Fire .... 4.00 LAFF ARGUE, A. Attack in Trench Warfare 50 MAGUIRE, E. Attack and Defense of Coast Fortifications . . 2 . 60 MERCUR, JAMES Attack of Fortified Places 2.00 MOSS, JAS. A. Applied Minor Tactics 1.00 MOSS, J. A. Trench Warfare 1.26 NICHOLSON, W. A. Artillery Fire 1.60 SMITH, J, S. Trench Warfare 1.60 SWINTON, E. D. Defense of Duffer's Drift 25 THUILLIER, CAPT. H, F, The Principles of Land Defence 6.00 VON ALTEN Studies in Applied Tactics 2.00 WAGNER, A. L. Strategy 75 WISSER, JOHN P. Practical Field Exercises in Tactics and Strategy. Cloth 2.00 WALDRON, W. H. Tactical Walks 1.60 Digitized by Google TOPOGRAPHY BARNES, CAPT. JOHN B. Elements of Bfilitary Sketching and Map Reading $ .76 CARLOCK, P. D. Military Topogriphy and Photography . . . 2.60 COLE, E, P. IndiYidual and Combined Sketching .... 1.00 GRIEVES, L. C. Military Sketching and Blap Beading .... 1.00 GRIEVES, L. C. Military Sketching and Map Reading for Non- commissioned Officers 1.26 LAPPARGUE, ANDRE The Attack in Trench Warfare 60 MERTENS, translated by W, KRUGER Tactics and Technique of Riyer Crossings . . 2 . 60 REED, H, A, Topographical Drawing and Sketching . . . 4.00 REINHARDT, C. W, Lettering for Draughtsmen, Engineers, and Stu- dents 1.00 SHERRILL, C. O. MiUtary Map Reading .90 SHERRILL, C. O, Military Topography 2.60 SHERRILL, C, O. Rapid Reconnaissance Sketching 1.26 SMITH, R. S, and McMILLAN, C. Manual of Topographical Drawing 2.26 SWEENEY, W. C. Sketching Methods 1.00 WILSON, H. M. Topographic Surveying 3 . 60 TRANSPORTATION AND RATIONING Army Horse in Accident and Disease (1909) Mounted Service School .86 Army Transport Service Regulations 60 Digitized by Google VAN NOSTRAND'S MILITARY MANUALS 73 Pages Illustrated 3HX5H Postpaid 30c. Baynet Training Manual Used by the BRITISH FORCES The material in this book is from the latest British Traininjg Manual (1916), which is based on their experience, and their forces as well as ours are now being trained in accordance therewith. The methods described have been adopted for use in training the United States forces. 150 Pages Illustrated 3 Folding Plates zH^SH Postpaid 60c • Operation and Tactical Use of the Lewis Automatic Machine Rifle Based on the Experience of the European War '"?y".'S;tto?'"' Col. I. N. LEWIS, U.S.A. The descriptive text is full and accurate in detail, while the system of preliminary and practical field iiistruction as outlined follows closely that now employed at the various machine gun schools and special instruction camp>s in England, France and the United States. 90 Pages Illustrated s Folding Plates iH^SH Postpaid 50c. The Attack in Trench Warfare By Capt. ANDRE LAFFARGUE xssrd Infantry, French Army Translated by an Officer of Infantry A careful study on the general and detailed aspects of the tac- tics of the attack in trench warfare, one of the important features of which is a study of the methods of training infantry units for this class of military operations. General Joffre was so impressed with the value of this book that he had it published to the French Army before giving it out for general publication. Digitized by Google VAN NOSTRAND'S MILITARY BOOKS a7S PftfM los niiistrmtioiit 4 Folding PUtet 6x9 Postpaid $2.50 TAaiCS AND TECHNIQUE OF RIVER CROSSINGS BY COLONEL MERTENS TRARSLATBD FKOM THB OBUfAH BT WALTER KRUEGER Major U. S. Army Presents a carefully thought out scheme of a way in which river crossings may be effected and of how the attacker, once across, may be met. 157 FMr«* 40 Uuttratioiit 3 PUtet 5x7 Cloth Postpaid ta.oo MILITARY OBSERVATION BALLOONS (CAPTIVE AND FREE) A complete treatise on their manufacture, equipment^ inepection, and handling, with special instructions for the training of a Held balloon company BY EMIL J. WIDMER This book is based on the Balloon Manual of the German army, including drill and equipment used at the beginning of the present war. Digitized by Google MOSS, MAJOR JAS. A. Peace and War Duties of the Enlisted Man . . $ .60 MOSS, MAJOR JAS. A. and WALDRON, MAJOR W, H. What Sammy's Doing . 75 PARKER, P, A, M. Control of Water 5.00 PARKER, RALPH M. An Officer's Notes 2.00 REY, JEAN (Trans, by J. H. JOHNSON) Range of Electric Searchlight Projectors . . . 4 . 50 ROBINSON, LIEUT. COL. W. Electricity 2.50 SOLANO, E. J. Camps, Billets and Cooking l.OC The Soldiers' Diary and Note Book ... 1.00 STEWART, M. B. Military Character, Habit, Deportment, Courtesy and Discipline 1.00 SWOOPE, C. W. Lessons in Practical Electricity 2.00 TURNER G. S. and FULMER J. J. Battle Fire Training ' 1.00 WALDRON, W. H. Scouting and Patrolling 25 WALSH, H. P. Takixig Bearings 1.00 WIMPERIS, H. E. Primer of the Internal Combustion Engine . . 1.00 ZU HOHENLOHE INGELFINGEN, PRINCE KRAFT Letters on Infantry 2.00 ZU HOHENLOHE INGELFINGEN, PRINCE KRAFT Letters on Cavalry 1.75 ZU HOHENLOHE INGELFINGEN, PRINCE KRAFT Letters on Artillery 2.M Digitized by Google THE WALDRON BOOKS By Major WILLIAM H. WALDRON, 29lh U. S. Infantry SCOUTING AND PATROLLING Cioth Bound •;- Fits the Pocket WHAT TO DO— HOW TO DO IT Covers the duties of the individual scout and the opera- tions of the Patrol in **^'o Man's Land.'* Postpaid - 50c Elements of TRENCH WARFARE Ciotk Bound -:- Fits the Pocket Compiled from the latest information of how they are going about it on the Western front. Profusely illustrated. Postpaid - - - 75c. COMPANY ADMINISTRATION A reference book that no Company Commander, First Sergeant or Company Clerk can afford to be without. The most complete and practical treatment of the subject that has been produced. Postpaid - - - $1.25 TACTICAL WALKS A system of instruction for Officers and non-commis- sioned Officers for the duties that will devolve upon them in actual service. No ehttering generalities— a book of detail — ^just what to do. Written so you can understand it. Postpaid - - . $1.50 The Infantry SOLDIER'S HAND-BOOK An illustrated text-book covering the training of the infantry soldier for war. Every soldier in the Army should have a copy. Postpaid - - - $1.00 Digitized by Google VAN NOSTRAND'S MILITARY BOOKS THIRD EDITION X as Pages Illustrated 5 Folding Plates aH^sH Cloth Postpaid 75c. ELEMENTS OF MILITARY SKETCHING AND MAP READING BT JOHN B. BARNES Major Barnes' book is based on an expert knowl- edge of the subject as taught by the Service Schools, Fort Leavenworth, and an appreciation of the needs of beginners through his wide experience as an in- structor of National Guard Officers, and at Officers' Training Camps. Written with a view of self - instruction, with new and original illustrations that explain simply and graphically the points that are usually found troublesome by beginners. The new and important subject of Landscape Sketching is thoroughly explained and illustrated. Map reading is explained in a few pages. Scales are already constructed. Pocket size, so it can be carried along conve- niently. Digitized by Google VAN NOSTRAND'S MILITARY BOOKS 331 P«c«t sx PUtei— Many in Colors Pocket Size Price Sx.oo MILITARY and NAVAL RECOGNITION BOOK A handbook on the organization, insignia of rank, and customs of the service of the World's Important Armies and Navies. BY Lieut. J. W. BUNKLEY U. S. Navy A complete, correct and fully illustrated guide to the insignia of our army and navy as well as of those of the nations engaged in the war, compiled from official sources and useful alike to civilians as well as to the Army and Navy. You will need this book to help you recognize our boys at home and to distinguish the other boys "over there." D. VAN NOSTRAND COMPANY HEADQUARTERS SINCE 1860 for MIUTARY AND NAVAL BOOKS 2S Park Place NEW YORK Digitized by Google Digitized by Google Digitized by Google Digitized by Google rnr RETURN TO: CIRCULATION DEPARTMENT 198 Main Stacks LOAN PERIOD 1 Home Use 2 3 4 5 6 ALL BOOKS MAY BE RECALLED AFTER 7 DAYS. Renewals and Recharges may be made 4 days prior to the due date. Books may be renewed by calling 642-3405. DUE AS STAMPED BELOW. APT ' ?noz ULT-t: . tl>ufc 1^ FORIWNO. DD6 50M 5*02 UNIVERSITY OF CAUFORNIA, BERKELEY Berkeley Callfofnia 9472O-6000 i YB 04288 iL£J^^LIBRARiES~ C0M77'iaa33 UNIVERSITY OF CAUFORNIA LIBRARY W oogle ,/>! ^,.. '% n^ » '^-