OcTOBES T, igoS.] 



THE INDIA RUBBER WORLD 



-7 



Aeronautics and the Rubber Industry. 



THE past month has been prolific of news bearing upon aerial 

 navigation — a subject which now interests the general 

 newspaper reader everywhere, as well as engineers, mili- 

 tary authorities and other scientific classes. To the casual reader 

 of the daily reports of the current exploits of Wright, Baldwin, 

 Zeppelin, ct al., it may be surprising to be reminded that just ly 

 years ago Mr. Octave Chanute, then president of the American 

 Society of Civil Engineers, and regarded as perhaps the best liv- 

 ing authority on "Progress in Aerial Navigation," in which he 

 admitted that the success attained had been small. He said : 



Within the last decade a balloon has been driven against a moderate 

 wind, and a nian is said to have flown a hundred yards near Paris. 

 So that it may t>e that, as Professor Langley (then secretary of the Smith- 

 sonian Institution) says, the problem of aerial navigation is about to pass 

 into the hands of the engineers. 



To sum up Mr. Chanutc's paper, published so recently as i8gi, 

 he could record little more advance in aerial navigation than "a 

 great change in the attitude of popular opinion toward the whole 

 subject. It is no longer regarded as wholly impracticable and 

 visionary." In other words, a man might at least talk about "liv- 

 ing" without being considered a "crank," 



Mr. Chanute has lived to sec dirigible balloons and various 

 forms of aeroplanes apparently capable of practical use. Look 

 back to Mr. Chanute's cautious statement — "a man is said to ha\ r 

 flown a hundred miles near Paris" — and compare it with Count 

 Zeppelin's flight of 300 miles within 20 hours, in a dirigible air- 

 ship, 435 feet in length, with 220 HP. motors. Not only is the de- 

 velopment in aerial navigation of vast interest in military circles. 

 and from other practical standpoints, but it is being taken up with 

 enthusiasm as aflfording a new field in sports. It is understood 

 that at the coming eleventh Exposition Internationale de I'Auto- 

 mobile, du Cycle, et des Sports, at the Grand Palais, Paris, an 

 extensive section will be devoted to balloons and flying machines. 

 But the object of this article is not so much to record the de- 

 tails of the progress that has been made in aerial navigation, as 

 to call attention to the great importance to the india-rubber trade 

 of ultimate success in this field. As the automobile would be im- 

 practicable without rubber tires, neither the balloon nor the aero- 

 plane is capable of the best development without rubber. Par- 

 ticularly is this true of the balloon. 



It is true that the coating of rubber in balloon fabric can be 

 replaced with a coating of varnish, and in France many sailing 

 balloons are constructed of a varnished fabric, but the varnish is 

 by no means as impermeable as rubber. Moreover, the varnished 

 fabric has other disadvantages, in addition to its lack of capacity 

 to retain gas. It is, for instance, a better conductor of heat, and 

 for this reason the gas, in a varnished balloon, is lieated more 



quickly by the sun's rays and cools more rapidly in the shadow 

 of a cloud, causing a greater loss of gas than occurs in the case 

 of a balloon made of rubberized fabric. Heat also causes the 

 varnish to become sticky, making packing more risky, and the bal- 

 loon is likely to be damaged by sticking together when unpacked. 

 A low temperature hardens the varnish and the fabric is brittle 

 wlien folded, all cf which factors make the varnished balloon 

 less durable than one made of rubberized fabric, the latter being 

 used for all the best and largest balloons. 



For motor balloons, or dirigibles, owing to the much higher 

 gas pressure required, it is next to impossible to use varnished 

 fabric. The loss of gas within a prescribed period would lie 

 altogether too great. The high degree of perfection to which 



Intkrnationai. B.m.i.oon R.\<e .\t Hurlingham. 



I From The Autoniotor lottnial.] 



the rubberized balloon fabric has been brought, in Germany, is 

 proved by the fact that the manufacturers guarantee that it will 

 not lose more than 10 quarts of hydrogen gas per square yard, in 

 24 hours, in spite of the pressure under which it stands being 

 considerably higher than the surrounding atmosphere. 



In the development of balloon fabric Germany has held the lead 

 hitherto, as France has in the construction of automobiles. But 

 as other countries are becoming independent of France in respect 

 of auloniobilc construction, so Germany must look for competi- 

 tion in the supplying of balloon fabric. The I'nitcd .Sl;iti->. giiveru- 

 ment has encouraged the production of balloon fabric by domestic 

 manuf.icturers, and the gas bag used in tlie first American war 



^IS'SESS 



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■■ .^•''.-Aa 



International Balloon Contest at the Aero Club's Grounds, Hurlingham, England. 



[Panoramic view of the balloon paddock, showing the whole of the 31 hallonns in i>osition, in pr* cess of inflation from a 14-inch gas main, 

 large white "mat" to the right is the starting line. — From The Autonwtor Journal."] 



The 



