THE INDIA RUBBER WORLD 



[January 1, 1919. 



The Rubber Trade in Great Britain. 



By Our Regular Correspondent. 



WRITING, as I do, with the sounds of revelry and bell- 

 ringing in my ears, on an occasion which need not be 

 specifically mentioned, it is not particularly easy to com- 

 pose one's thoughts to the somber routine of wriiing on purely 

 trade matters. This, however, is all I am entitled to do' in these 

 columns, and the first matter which inevitably comes to mind is 

 the effect that the welcome cessation of hostilities will have on 

 those hives of industry, the rubber works. 



That there must be a transition period of general upset goes 

 without saying, but anything like stagnation to follow the 

 cessation of war demands is most unlikely, owing to the deflec- 

 tion of stocks of all sorts of rubber goods in general civilian use. 

 The rubber trade being concerned with equipment, its products 

 will be wanted for some time, as there is no question of an imme- 

 diate demobilization, though naturally the rush of .work to get 

 out orders has subsided and there will be no occasion for over- 

 time. I suppose that manufacturers, especially proofers. would 

 welcome a more sudden change from war to peace conditions, so 

 that they could tackle their civilian trade, as this would be far 

 more profitable than government work, which is now all ^pne 

 on a strictly cost basis and yields only a fair— perhaps some 

 would call it an unfair— profit. No very rapid change could, how- 

 ever, be made all around, as so much of the cloth in stock has 

 been woven and dyed for government purposes, and it would be 

 quite unsuitable for the civilian trade. 



THE RAW RUBBER POSITION. 



With regard to raw rubber, it is generally thought that there 

 will be no return, for some time at any rate, to the two shillings 

 per pound figure. I gather that the bulk of the stocks held by 

 manufacturers was bought at 2s Ad. or 2s.Sd. a pound, the de- 

 mand having been largely satisfied before the fall to 2s. per 

 pound. As a manufacturer said to me: "All of us are not ex- 

 tremely wealthv men, nor do we want to buy for too far ahead, 

 so there was no rush to buy rubber at 2s." Certainly, if there had 

 been, the price would at once have gone up in accordance with 

 customary market procedure. If the rubber-growing interests 

 could have foreseen the present condition of affairs they would 

 not have asked for a government committee, which has got to work 

 just as a general feeling is making itself articulate in the country 

 to get back to self-management. 



TESTING RAINPROOF CLOTH. 



At the meeting of the Manchester section of the Society of 

 Chemical Industry, on November 8, a paper on this subject was 

 given by Dr. G. Martin and James Wood. Dr. Martin said that 

 the want of a rapid standard method had been felt in recent 

 times when large quantities of material had to be reported upon 

 quickly. He gave a short account of the various methods of 

 rainproofing with aluminum acetate, gelatine, paraffin wax, etc., 

 and emphasized that such goods, unlike rubber goods, are per- 

 meable to air, and, except in the case of wax, to a more or less 

 extent to water. They are popular because they were more 

 healthy than rubbered goods and will always be in demand, he 

 thought, for town use, where shelter from heavy rain is always 

 at hand After describing Gawalowski's waterproof testing ap- 

 paratus, he then described the War Office drop test, which is a 

 simple form of apparatus and allows results to be obtained 

 rapidly bv a process which imitates the natural fall of rain on ■ 

 the cloth. Drops of water are allowed to fall on a piece 

 of the cloth which is laid on blotting paper on .a sheet 

 of glass placed at an angle of 4S degrees. The observer watches 

 the glass from behind, and when water is seen on the blotting 

 paper the number of drops of water is noted by the burette. 



reading. The results of many tests were given by Dr. Martin, 

 variation as wide as 6 and 18 drops being noted on the same piece 

 of cloth. 



In the subsequent discussion it was urged by two or three 

 speakers that to take the mean of such divergent figures as the 

 result of a test was a very unscientific proceeding. Dr. Martin, 

 however, maintained that though the test was not all that it 

 might be, it still gave very useful results, and, at any rate, 

 was much superior to the dash test and the trough test com- 

 monly used in the trade. Mr. Terry said that it was obvious 

 that such a test would not be of any service in the case of rub- 

 bered goods in which the government relied upon the number of 

 grains of proofing contained on a certain superficial. He also re- 

 marked that inequalities of spreading are a common feature in 

 rubbered goods and suggested that Dr. Martin might look into 

 this matter in the case of showerproofings, as it might explain- 

 the wide variation in the figures he had given. In the course of 

 his remarks Mr. Terry referred to the humorous skit which ap- 

 peared in the September number of The India Rubber World, 

 the recital of the dialogue between the British and American 

 soldier regarding the lalter's rainproof causing considerable 

 amusement. Dr. Martin said that so far he had not tackled the 

 question of rubberproofings. but it was his intention to do so. 

 DETERMINATION OF LAMPBLACK IN RUBBER. 



I see that a method for effecting this has been communicated 

 to the Rubber Section of the .A.merican Chemical Society by A. 

 M. Smith, of the Bureau of Standards. I have seen only a short 

 abstract of the method, which consists of the removal by sol- 

 vents and nitric acid of all substances which would change 

 weight on ignition, and estimation of the carbon by the loss on 

 heating. It is stated that the method is found sufficiently accurate 

 for commercial work when a small correction is made to provide 

 for the errors of the determination. I may say that over 20 years 

 ago I worked out a method on very similar lines, though I have 

 never ventured to return my results as more than a fair approxi- 

 mation. A good deal depends upon the nature of the lampblack. 

 I remember saying something about my method to C. O. Weber 

 and he threw cold water on it by saying that lampblack was 

 considerably attacked by strong nitric acid. Presumably it would 

 be mainly the hydrocarbons in the oily blacks that would be at- 

 tacked rather than the free carbon, of which the American gas 

 blacks are mainly composed. At this juncture, then, if nitric acid 

 is used in the process, it would be more nearly correct to refer to 

 the determination of free carbon than of lampblack in rubber. 



A rubber tire with a large amount of gas black is, of course, a 

 simpler problem to tackle than is a common-grade mixing with 

 a few per cent of inferior black, and I have had in my experience 

 rubber samples in which I have found it impossible to obtain a 

 figure in which I had confidence. With a high-grade simple mix- 

 ing, however, I can quite support the claim that the method as 

 outlined will give most useful results, and especially in cases 

 where the lampblack used is of a standard quality as ta 

 specification. 



WASTE RUBBER SALVAGE. 



A notice recently appeared in the press that by arrangement 

 with the government departments concerned, national collection 

 of waste rubber was to be undertaken with the object of bene- 

 fiting the funds of the Red Cross. I have not been able to get 

 any details of the project and find that in reclaiming circles it is 

 looked upon as one more of the many brilliant ideas which have 

 been launched during the progress of the war with the same 

 laudable object in view. Certainly one of the difficulties in the 



