May 1. 1916.1 



THE INDIA RUBBER WORLD 



rubber of balloon fabrics, forms copper sulphide which rapidly 

 deteriorates the rubber. For this rca.i;on. therefore, fittings and 

 accessories should never be allowed to come into contact with 

 the surface of a balloon. Further, rubber that has been 

 handled in copper vessels should never be employed in proofing 

 balloon materials. Even iron, especially when it is rusty, will 

 cause trouble if it is allowed to touch rubberized balloon fabric 

 for any length of time. The enormous surface a balloon offers 

 to the contact of air and light is also a cause for the generation 

 of sulphuric acid in the rubberized fabric of which it is made. 

 One manufacturer attempts to lessen the effects of these agents 

 by adding pitch, asphalt, or paraffin, to the proofing mixtures, but 



Stern- View of "L'Eclaireur C 



(I-'he.nch Xo.v-Rigid). 



it must also be borne in mind that the purer the rubber the better 

 it will stand air and light. .Another cause for the deterioration 

 of balloon fabrics exists in the methods employed in bleaching 

 and preparing the fibers used in the weaving of these materials. 

 To preserve the balloon itself, it is important that the place 

 where it is kept be as dry and dark as possible. Yellow or red 

 windows are desirable for the shed or hangar in which the balloon 

 or balloon material is to be kept, especially if the windows have 

 an eastern exposure. Balloons should ahvays be dried, like the 

 balloon material, by natural air. but not in the sun. 



OUR NEW NAVY DIRIGIBLE. 



"T^HE first dirigible owned by the United States Navy is shown 

 •^ here as set up in the State .\rmory at Hartford, Con- 

 necticut. It is the first of several which it is hoped the govern- 

 ment will order in its new issue of preparedness. The dirigible 

 is 175 feet long. 35 feet in diameter and 50 feet high. It weighs 

 5.000 pounds and has a lifting capacity of 2,000 pounds more, 

 or a total of 7,000 pounds. The envelope will contain 150,000 

 cubic feet of hydrogen and the craft will travel at a speed of 

 35 miles an hour. The car is 20 feet long and 5 feet wide, and 

 will accommodate a crew of eight. It is built so that it will 

 float on water. Motive power is provided by an 8-cyIinder gaso- 

 lene engine operating two propellers, one on each side of the 

 car. The balloon proper consists of two parts, an outer envelope 

 and two inner balloonetts. The envelope is filled with hydrogen 

 gas and balloonetts are to hold air which is pumped into one 

 or the other or exhausted, as is needed to elevate one or the 

 other end of the balloon that it may rise or descend. The entire 

 strain falls upon the outer envelope, which for this reason is 

 made of a very strong, double texture fabric, about 2,500 yards 

 being required. This fabric w-as furnished by the United States 

 Rubber Co., and represents a large amount of study, time, effort 

 and expense. The outer fabric is cut in pieces at an angle of 45 

 degrees from the line of weaving, joined together in a strip the 

 same width as the inner fabric, which is run through straight 

 with a warp when the two, already proofed, are cemented to- 

 gether and vulcanized. Great care has been taken that there 

 are no thick threads or knots, and that it is thoroughly im- 

 permeable, no holes even of the smallest possible size being 

 Itermitted. The inner fabric is dyed green and the outer, orange. 

 It was manufactured under the direction of W. A. Gibbons of 

 the United States Rubber Co.'s general laboratories. The 

 balloonetts are of single texture and of lighter weight, this be- 

 ing feasible as no heavy strain will come upon them. The shap- 

 ing of the big bags, and the setting up of the balloon was done at 

 the Naugatuck factory of the company. The preparation of the 

 fabric was at the Cambridge factory. We understand that the 

 company is now at work upon other orders for similar fabrics 

 from balloon and aeroplane manufacturers, and that it has quite 

 an extensive and varied line of similar fabrics of single and double 

 texture, in a variety of colors especially suited to such purposes. 



K.iBLE Airship D\'-1. 



