September i, 1909.] 



THE INDIA RUBBER WORLD 



427 



India-Rubber in Aerial Navigation. 



WHAT has been said so often of india-rubber as a neces- 

 sity in coniKction with the automobile seems liable to be 

 repeated, and with good reason, in connection with diri- 

 gible balloons an<l Hying machines, TI>c InJia-Hubbcr Journal 

 says : 



"It is not astonishing to learn that ubiquitous rubber is an im- 

 portant feature in the coming vehicles. The cloth for airships, 

 balloons, or aeroplanes, is proofed with rubber, while the machine 

 with which M. Bleriot flew over the English channel w^as equipped 

 with a long india-rubber cylinder filled with air, which would 

 have acted as a float had the aeroplane fallen into the water. The 

 wheels of the machine were fitted with pneumatic tires, and 

 there were other rubber fitments used in the machine, so that 

 the demand for rubber is likely to survive even if airships take 

 the place of land or water carriages." 



There is now in progress at Frankfort-on-the-Main the Inter- 

 nationale Luftschiffahrt-Austellung (International Airship Exhi- 

 bition), not the least interesting feature of which consists of 

 exhibits of rubber proofed fabrics for the various machines which 

 have been designed for aviation. The notes which follow, in 

 reference to the more notable exhibits at Frankfort, are presented 

 here with apologies to the Gnmmi-Zeitiing. 



* * * 



The Continental- Caoutonc- und Guttaperch'a-Compagnie 

 (Hanover) has an exhibit of "Continental" balloon and aeroplane 

 fabrics which is most tastefully arranged. "By means of enor- 

 mous photographs the company show airships constructed of 

 Continental fabrics. There are a good many of them, since the 

 Continental balloon fabric has been used for the construction of 

 nearly all the airships in the world. The Continental balloon and 

 aeroplane fabric is also frequently represented, even in the case 

 of the balloon Preussen, with a gas capacity of 8,400 cubic meters 

 [= 296,654 cubic feetl, which although about 12 years old, does 

 not show the slightest defect, and is still being used for making 

 ascensions. This balloon attained, as early as 1901, the record 

 height of 10,500 meters \— 34.449 feet]. The collection of vari- 

 ous kinds of balloon, aeroplane and airship fabrics manufactured 

 by the Continental company is exhibited in a most comprehensive 

 manner." 



* * * 



The most conspicuous object of the exhibit of the Vereinigte 

 Gummiwaarcn-Fabriken Harburg-Wien is a new spherical bal- 

 loon of 945 cubic meters capacity, constructed of diagonally lined 

 cotton fabric, with complete equipment. In consequence of its 

 nice, attractive appearance, this balloon found a purchaser as soon 

 as exhibited, and, as it has already been definitely sold, the manu- 

 facturers are compelled to have a new balloon constructed for 

 the exposition. A novel feature of the company's exhibit con- 

 sists in a valve for free balloons. In this valve the joints of the 

 hinges which connect the valve disc with the upper valve ring or 

 hoop, are provided with springs, these springs being the main 

 feature of the device, inasmuch as they insure absolutely reliable 

 operation, since the valve disc must necessarily always return to 

 the same position. The valve is made tight by means of a folded 

 rubber band, tapering towards the top, which presses against a 

 rubber membrane. .Applications for patents on this valve have 

 been filed. 



In addition to a number of samples of fabrics for free balloons 

 and power balloons, as well as of aeroplane fabrics, the company 

 also exhibits a raincoat especially adapted to the requirements 

 of aeronauts. The reason for providing this garment was the 

 experience gained during a balloon trip made recently from 

 Cologne in rainy weather, during which the aeronauts got a most 

 thorough wetting. The material used for the garment has a thick 



rubber coating in the outside, so as to prevent it from absorbing 

 any water, even during the most severe rain storms. The coat 

 has only one opening, the same being at the neck, and a special 

 flap made of rubber cloth and attached to the coat under the 

 opening, prevents water from entering through the same. The 

 coat is provided with a hood for protecting the head. For pro- 

 tecting the feet, the company likewise make rubber cloth boots 

 reaching up to the knees, and sufficiently large for putting them 

 on while wearing common shoes or boots. Various other articles 

 of minor importance will also attract the visitor's attention. The 

 covering of the model balloon exhibited by the Rheinisch-West- 

 fiilische Motorluftschiff-Gesellschaft as wxll as that of the large 

 power balloon, now nearly coinpletcd, were likewise made by the 

 Vereinigte Gummiwaarcn-Fabriken Ilarburg-Wien. 



The Mitteldeutschc Gummiwarenfabrik. Louis Peter, A.-G., of 

 Frankfort o/Main, are exhibiting a spherical balloon, as well as 

 supplies for balloon manufacturers. 



* ♦ K 



The .'\kliengesellschaft Metzeler & Co., of Munich, has fol- 

 lowed the plan of exhibiting only its achievements during a 

 period of nearly 20 years in the manufacture of balloon fabrics. 

 Its exhibit is consequently not made conspicuous by large deco- 

 rative designs, but shows balloon fabrics exclusively. A large 

 revolving stand, provided with 10 arms, carries a corresponding 

 number of samples of various balloon and aeroplane fabrics, com- 

 prising one, two and three ply fabrics with and without outside 

 rubber coating. The concern shows fabrics for ordinary balloons, 

 airships of the rigid, semi-rigid, and non-rigid types, as well as 

 fabrics for the wings of flying machines. It is a well-known fact 

 that the Metzeler concern has supplied the fabric for numerous 

 balloons; no less than 15 balloons constructed of Metzeler bal- 

 loon fabric having taken part in the Gordon Bennett aero con- 

 test in 1908. The airship "Parseval I," and part of the airship 

 "Zeppelin II," are likewise constructed of the same material. 

 Balloons made of Metzeler balloon fabric have, moreover, gained 

 numerous victories. The balloon "Pomern," for instance, which 

 was awarded the Gordon Bennett prize in 1907, has become 

 widely known. During the current year balloons constructed of 

 Metzeler balloon fabrics were again successful. The balloons 

 "Hildebrandt" and 'Schlesien" came out victorious in the pre- 

 liminary contest for this year's Gordon Bennett aero contest, and 

 were awarded first and second prizes. At the international bal- 

 loon race held in Cologne on June 29, two first prizes were 

 awarded to balloons constructed of Metzeler fabric. A number of 

 photographs exhibited by the concern, and showing interesting 

 incidents of balloon ascensions and landings, proved very attrac- 

 tive to the visitors, and the entire exhibit makes the impression 

 that the company's earnest efforts have been crowned with most 

 satisfactory success, and that the concern will undoubtedly take 

 its place among the foremost manufacturers of balloon fabrics. 



* * ♦ 



The Rheinische Gummiwarenfabrik Franz Clouth, Koln, have 

 sold to the "Ila" a completely equipped free balloon of 900 cubic 

 meters capacity. Yellow coloring has hithertofore been used 

 for protecting the rubber against decomposition by the action of 

 the sun rays, because it reflects the largest number of rays. 

 More recent investigations, however, make it appear probable 

 that the same purpose may be attained, even more eflfectively, 

 by using red coloring. Neither does it appear improbable that 

 red colored balloons will stand out less conspicuously against 

 the background cf the sky than yellow colored balloons, a 

 factor which is of importance from a military standpoint, be- 

 cause it would make effective shooting at balloons more diffi- 

 cult. In the spring of the current year a balloon caught fire in 



