September 1, 1915.] 



THE INDIA RUBBER WORLD 



&+9 



The Manufacture of Balloon Fabrics in Europe. 



IX balloon construction rubberized fabrics are used much more threads arc used for both weft and warp. Careful calendering 



extensively than for aeroplanes, for dirigible fabrics must he takes out all folds and creases ["he fabric must be thoroughlj 



gas-proof and at the same time have .meat tensile strength, washed and dried ' eing rubberized. Once this is 



Fabrics treated with linseed oil will not hold hydrogen and arc the fabric is passed through a calender, the rubber is spread 



therefore useless. Dirigible hailn.m hags are made of "doubled" and the fabric allowed to season in a place neither t iry nor 



cotton fabrics, the layers being held together by two thicknesses too humid. The following table giVes the characteristics and 

 of rubber— one of pure gum, uncured, the other of vulcanized price in marks and dollars (before the wan of six sorts oi 

 Para; and the inside of the whole is coated with vulcanized ton balloon fabrics manufactured by a leading German corn- 

 rubber, pany: 



These "doubled" fabrics weigh from 320 to 340 grams per .,, . ., _ ,. , , 



, , , . WcikIh. Bn ..! ing 



square meter t 1.(14 to 1.10 ounces to the square toot), and their _ in grams Number of pei running meter 1'riccper 



•i .i .- i 4, 1,. . t -nr, i -l (1S.432 grains, troy) threads per (39.37 inches) -'mare meter 



tensile strength is from l.-UX) to I.jOO kilograms per running a square me.er ^ 



meter (78.39 to KW> pounds to the inch) on fabric 0.3 milli- Xos - (10.76 so, fei Warp. k7 Dollars. 



meters (0.118 inches) in thickness. Acetate of cellulose is also \]y//.[\\ 5 . \*° g.333 



used for coating balloon fabrics; for. like triacetine varnish, jj ,SS",22 s *° IJ0 



- 4 103-105 950 900 1.35 Ot'l 



acetate of cellulose allow-- the balloon fabric to retain all its 5 115.117 1.200 1.45 



suppleness and does not injure it as does linseed oil. Fabrics 6 ' '"" l - so ° '- 60 ' 



coated with this composition are absolutely hydrogen gas-proof. Xos. 1, 3 and 5 answer practically all purposes. Fabric No. 1 



Linseed oil is used for coating spherical balloons on account of is made especially for small aerostats, such as registering bal- 



ZEPPELIN RIGID 



METAL PARTITIONS 



OUTER lABHtC COVERING 

 METAL EMUE 1 K»TT..*TIMG 

 GAS SAGS FROM AIR 

 PRESSURE SET UP Br 

 MICH 3 



jmm — " 



CARS SET CLOSE TO BODY 



THUS DIMINISHING 



AIR RESISTANCE 



PARSEVAL NON-RIGID 



LEBAUDY SEMI-RI6I0 



Types of Dirigible Balloons. 



its low cost, but the fabric lasts much better when treated with 

 acetate of cellulose. 



1 \BRICS. 



Silk and cotton fabrics arc most generally employed in the 

 making of balloons. Pongei -ilk is considered best, but silk 

 taffeta is also used. The advantage of silk is that it is very 

 light for its great strength. Its disadvantages are its cost, its 

 tendency to become brittle and the faculty it has of accumulat- 

 ing electricity. The ramie fabric-, employed in the construction 

 of some French aeroplanes, do nol take rubber easily, and for 

 that reason their role in balloon construction lias been limited. 



Cotton fabrics are probably best suited and certainly most 

 generally used in the construction of balloons. Egyptian and 

 East Indian are considered best, the English, Bohemian and 

 Alsatian weaves being the most highly favored. The thickness 

 of these fabrics varies from 0.015 to 0.037 millimeter (0.00059 

 to 0.00146 inch 1. Fibers vary in length from 20 to 30 milli- 

 meters (0.78 to 1.18 inch), and the very best English balloon 

 fabrics are made of Lea-Ashland-Mako cotton. The threads 

 must he evenly twisted, perfectly round and of the same thick- 

 ness throughout. The same number and the same weight of 



loons, where it is used single-fold. It also is used, 



bled" 1 double-fold 1, for making the compartments of 

 dirigible balloons, such as the Zeppelins, in which the plies are 

 assembled parallel, and iii French balloons of the "Zodiac" make, 

 where it is employed in making the inside "ball r air 



sacks used for "trimming" tin balloon. Fabric No. 3 i- used 

 single-fold for the outer cover of "Zeppelins" and "Schiitte- 

 Lanz" dirigibles; also for building signal balloons and kites, 

 while doubled, it serves in the construction of small dirij 

 of the "Ruthenberg," "Lebaudy," "Zodiac" and "Clouth" types; 

 also for spherical balloons. Fabric No. 5, doubled, is used in 

 building dirigibles like the "Suchard." Used in combination with 

 one another, or used singly, the three types of rubberized : 

 — Xos. 1. 3 and 5 — offer almost unlimited possibilities. Cheap 

 fabrics are always full of knots, bare spots ind oilier irregu- 

 larities and therefore cannot be considered as proper for bal- 

 loon construction. Further, thej are heavy and not e; - to 

 rubberize. 



1 ' H 1 iK INT,. 



The coloring of rubberized balloon fabric- is of vital ini] 



tance. for light and ultra-violet rays arc especially us to 



