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THE INDIA RUBBER WORLD 



[NOVEI 



feel sure, and no doubt they will also be able to read, as in the 

 earlier edition, of a variety of processes that have been tried 

 but never achieved any useful purpose. In an industry like 

 ours where new ideas are always being put forward, it is de- 

 cidedly useful to be able to point to the fact that the vaunted 

 novelty of today is identical with a proved failure of the past. 

 The other day I came in contact with a certain chemical used 

 in a more or less recent process in a rubber works and looked 

 into a number of books to find out something about it. Rather 

 to my surprise it was not mentioned. I then thought of the 

 book under notice, and there I found the exact information I 

 wanted. A fortiori, those who have no series of chemical works 

 at hand cannot fail to find the book a valuable consultative 

 medium. 



RUBBER CARD CLOTH. 

 Makers report trade as being very good, but that owing to 

 ihortage of labor and other current difficulties, it is by no means 

 easy to fill orders promptly. With regard to this business I 

 remember that at the first London rubber exhibition it was 

 stated that the card cloth manufacturers were yielding the point 

 of using plantation rubber, and that it had been tried with suc- 

 cess for block rubber. Although unvulcanized rubber-faced 

 cards are expected to last as long as fourteen years, enough 

 time has now elapsed to test the wisdom of the change from 

 Brazilian Soft Fine and it would be interesting to have the 

 results published. This, however, is where difficulties always 

 seem to arise in our trade experiments and I am not hopeful 

 of seeing anything authoritative in print. All I can say myself 

 with certainty on the matter is, that some firms have not yet 

 deviated from their procedure of forty years ago. With re- 

 gard to the vulcanized rubber cards made by certain firms for 

 use in woolen mills, as these have a much shorter life, I do 

 not see why there need be the same anxiety in making a change. 

 A considerable export trade to all cotton-spinning countries 

 has always been a feature of the English manufacture, but 

 this has been much interfered with by the war, and many 

 orders in hand are remaining unfilled. This is especially the 

 case with Russia, where a branch works was once started by a 

 prominent English company, but was stopped after a few years. 

 In some German works making card cloth, the fabric and 

 steel points were brought from England and made into the 

 completed rubber-faced card in Germany. In the early days of 

 rubber reclaiming, the highest quality which was on the English 

 market was known as Rowley's Amazon rubber, which consisted 

 of the strippings of old unvulcanized card cloths. The name 

 will not be familiar to the younger generation, though no 

 doubt the material comes forward under some other designation. 

 CONTROL OF SULPHUR. 

 The article by Campbell Mac Culloch on the sulphur situation 

 in America in the August issue of The India Rubber World is 

 of great interest and deals with an important matter in a much 

 fuller way than would be possible in our technical press under 

 existing circumstances. After all, America has been a sulphur 

 producer for only about ten years, and supposing the working 

 of the deep Louisiana deposits by the Frasch process had not 

 come about, she must have been in a very awkward position 

 if she was still dependent upon Sicily for her supplies. It is 

 difficult for some people to believe that a country of the size 

 and presumed general resources of the United States can be 

 short of mineral products, but there are many minerals in which 

 she is greatly deficient. It appears that the pyrites deposits in 

 America have never been worked to any extent and that any 

 new mines cannot be brought into operation quickly enough to be 

 of service to replace the now diminished imports of foreign 

 pyrites. In these circumstances it certainly seems a good move 

 to adopt the thiogen process of recovering sulphur from waste 

 smelter gases, though the estimated cost of $10 to $13 a ton will 



probably be exceeded in practice. Tlie smelter fume problem 

 is of much greater importance in America than in any other 

 country, and whether the recovery of the sulphur proves a 

 commercial success or not, it may be made compulsory. In 

 pre-war days the smelter gases were not converted into vitriol 

 because it would have been impossible to market the prospective 

 amount of vitriol. In other countries smelter gases are made 

 to provide the vitriol for the adjacent manufacture of super- 

 phosphate. If the proposed government control of sulphur in 

 America works as smoothly as the similar control here, rubber 

 manufacturers will not have much to complain of. With char- 

 acteristic optimism, our Editor discourses of the possibility of 

 doing without sulphur in the trade, but as the bulk of the 

 urfjent work is for government purposes I think we may take 

 it that any government specification will continue to cite sulphur 

 and will not countenance the various alternative methods of 

 producing an apparently vulcanized article. One trembles to 

 think of the new female labor being put on to vulcanize rubber 

 with nitric peroxide or chlorine. 



BRITISH SCIENTIFIC PRODUCTS EXHIBITION. 



THE recent British Scientific Products Exhibition held in Lon- 

 don, says the "India Rubber Journal," had interesting ex- 

 hibits in connection with aircraft, gas traction and electrical man- 

 ufactures. A gasoline-resisting rubber hose that does not swell 

 when in contact with gasoline vi'as shown in use as connections 

 between lengths of metallic airplane gasoline tubing. A shock- 

 absorber cord used on the outer carriages of airplanes was also 

 exhibited. The three standard sizes now in use on British 

 machines are as follows : 



(1) (2) (3) 



Diameter H-inch !^-iiich H-inch 



Load at double extension 220 lbs. 140 lbs. 80 Iba. 



Number of double strands 266 172 95 



Rubber strands in two distinct coverings of cotton braiding 

 form the cord. Before braiding, the rubber thread can stretch 

 500 per cent, but to enable it to carry heavy loads it is stretched 

 to two or three times its length and held at that tension by the 

 braiding. The British cord carries a load of 140 pounds at 

 double extension, while the German cord carries 40 pounds. 



Balloon fabrics were also shown. The fabric for the outer 

 envelope of British observation balloons has two layers of cotton 

 fabric, folded diagonally in two plies, the outer one dyed green. 

 Between the plies is a layer of rubber, the free surface of the 

 inner ply also being rubber coated. The fabric is of Sea Island 

 or Egyptian cotton, 2.4 ounces per square yard, 118 threads per 

 inch in both warp and weft, and the strength is 54 pounds per 

 square inch. The rubber coating is 3.4 ounces per square yard 

 with a coating equal to .9 of an ounce per square yard on the 

 inside of inner ply. Total weight of the finished fabric is 9 

 ounces per square yard. Underneath one end of an observation 

 balloon is an open pocket or rudder which is composed of a 

 single-ply fabric of similar weight, strength and color to the one 

 above described, but the inside rubber proofing weighs 1.8 ounces 

 per square yard while the protective coating outside weighs only 

 .6 of an ounce per square yard. The total weight of this finished 

 fabric is 4.8 ounces to the square yard. The material of the 

 ballonet is like that of the envelope fabric, but lighter. The 

 rubber proofing is the same. Weight of fabric (untreated with 

 rubber) 1.8 ounces per square yard, 108 threads per inch (warp 

 and weft), strength 34 pounds per inch. Total weight of com- 

 plete fabric 8.1 ounces per square yard. The nurse balloon is 

 of stouter material, having three plies of cotton fabric folded so 

 that the warp and weft threads are parallel, the outer layer of 

 fabric being stouter than the other two and dyed green. There 

 are layers of rubber between the plies and on the outer surface. 

 The total weight of rubber used is 6.6 ounces per square yard, 

 and the complete fabric weighs 16.8 ounces per square yard. 



