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THE INDIA RUBBER WORLD 



April 1, 1921 



greater weakness under this so-called "life test" than do goods 

 made from stronger, better lots of rubber, but — here is a curious 

 apparent anomaly — goods containing a certain percentage of 

 resinous and bituminous substances, pitches, vulcanized oils, etc., 

 debarred by the chemical tests imposed by specifications, fre- 

 quently show up better in the so-called "life test" than do those 

 in which such substances have not been introduced. Again, goods 

 in which the free sulphur content is greater than the specifications 

 permit, often test belter after this accelerated aging process than 

 do goods in which the free sulphur is kept within the specified 

 limits. The subject is both puzzling and interesting. 



Physical tests before and after this so-called life test, indicate 

 variations in strength of plantation rubbers of the highest grade, 

 which so far seem to be quite beyond ordinary factory control. 

 I know that such strength variations in actual service are by no 

 means as serious as laboratory figures, regarded only as figures 

 or curves, appear to indicate, but they exist, and it seems to me 

 that candid expressions of opinions through your columns, based 

 upon actual experience, would prove to be not only of great 

 interest, but of mutual assistance. 



Superintendent. 



CONTRACT CANCELLATIONS CONDEMNED 



To THE Editor : 



r^ E.\R SIR : We have read your editorial as to contract cancella- 

 '■^^ tion in your March issue, vnth which we cannot feel in 

 any way in accord. The time to make a contract fair is when 

 the two parties are contracting for it, and not after the contract 

 has been signed. The privilege which you seem to uphold of 

 one party arbitrarily changing the contract because the market 

 has made it unprofitable for him to continue, is one which will 

 strike at the root of all business honesty. 



No one has been obliged to make contracts unless they felt 

 it to their advantage to do so, and the fact that their judgment 

 is wrong, does not justify them in cancelling them. A year and a 

 half ago many contracts held by the sellers became very unprofit- 

 able to them, by reason of the advance in the market. The 

 sellers carried out their contracts, as the buyers should do now. 



We agree that so far as deliveries and financing are concerned, 

 the buyer and seller should work thoroughly together, and that 

 each one should do what he can to make the burdens of the 

 other light enough to be carried, but the matter of cancellation 

 merely because the contracts prove unprofitable, is a diflferent 

 matter, and has never been the policy of American business. 



We are writing you as readers of your magazine, and we have 

 taken a great deal of pride in it, and therefore feel that we are 

 entitled to dissent from the view expressed. 



Meanwhile, we should like to say that for ourselves there has 

 been no epidemi,- of cancellation in the rubber industry. We 

 have not even been a.-l-ed to cancel a contract, and consider this 

 a distinct honor to the industry, but the encouraging of cancella- 

 tion of contracts is a policy v.hich we think ought to be con- 

 demned by a representative ti i it. paper. 



J. Spencer Turner Company. 



John E. Rousmaniere, President. 



New York, March 11, 1921. 



only too often take the latter wholly on faith. When a tire fails 

 them tlicy usually attribute the trouble to weakness in the shoe's 

 construction. 



Personally, I believe that the average well-made fabric or cord 

 reinforcement in a tire serves its purpose very well. When a 

 breakdown occurs the fault will be found generally in the rubber 

 compound used in the tread and sidcwalls. Pure crude rubber 

 must, of course, be incorporated with other substances to make it 

 serviceable for tire needs ; but, though numerous fillers are used, 

 the really worth-while ones are very few. The trouble with most 

 fillers is that there is an inter-friction among their particles, 

 which work on one another under service and heat the rubber 

 compound to such an extent that it gets over-cured, scales, loses 

 its life, becomes brittle, and dries or crumbles from its reinforce- 

 ment, causing cracking, blowouts, etc. 



While not denying that some fillers have real merit, my ex- 

 perience, confirmed by exhaustive tests, is that the most satisfac- 

 tory results are obtained with a zinc oxide tire compound. A rub- 

 ber company at Akron ran two tires at either side of a car on a 

 10-mile road covered with ice and snow. One tire had a proper 

 proportion of zinc o.xide. the other had no zinc in it. When the 

 latter was examined at the end of the run it was found badly cut, 

 but the zinc tire was unblemished. Compounding materials come 

 and go. but for all-around merit in adding toughness and tensile 

 strength to tire rubber zinc oxide is still unrivalled. 



The color of the tire is more or less due to the filler used. As 

 zinc oxide is white, the resulting tire is usually white or light 

 gray, but color is not always a certain indication, since zinc oxide, 

 because of its recognized value, is utilized in restricted percentages 

 as a filler in many black tires. 



The buyer is the ultimate arbiter. What he demands the maker 

 will perforce supply. If he takes without question what is 

 offered he will get what is easiest and cheapest to make. If he 

 demands a zinc tire, he will get a zinc tire and his money's worth 

 in service and satisfaction. 



C. A. Stedman. 

 160 Front Street, New York. 



TO DEMAND ZINC TIRES 



To THE Editor : 



DEAR SIR : While it is true that much more mileage is built 

 into tires than formerly, yet it is also a fact that still too 

 many tires, even among those of so-called standard make, fail to 

 reach a reasonable age in fair condition. Motorists often wonder 

 why, in comparing two makes of tires selling at a good price, 

 one should last long and give very good service while the other 

 proves to be very disappointing. The fact is that most motorists 

 know much more about judging cars and their mechanism than 

 they do about tires. Exacting in the choice of tlie former, they 



RUBBER TRADE INQUIRIES 



rHE hiquirics that foUoiv haz'e already been ansti'ercd; never- 

 theless they are of interest not only in showing the needs of 

 the trade, but because of the possibility that additional infor- 

 mation may be furnished by those wlw read them. The Editor is 

 therefore glad to have those interested communicate with him. 



(851 ) An inquiry has been received for a formula for a sub- 

 stitute for chicle in manufacturing chewing gum. 



(852) A reader asks for sources of information concerning 

 manufacture of dipped goods. 



(853) Request is made for the addresses of manufacturers or 

 jobbers selling paper in rolls to fit the Pierce tire-wrapping ma- 

 chine. 



(854) A chemical house asks for information concerning "Non- 

 Blow," used by the rubber industry. 



(855) Request is made for the addresses of manufacturers of 

 golf-ball winding machines. 



(856) A foreign manufacturer desires addresses of manufac- 

 turers of uncovered balls for making into tennis balls. 



(857) A reader inquires for the addresses of manufacturers 

 of felt for covering tennis balls. 



(858) A correspondent desires to purchase a bulb-spray for 

 testing waterproof material. 



(859) The address of the manufacturers of Rubies' plastic 

 pitch is requested. 



(860) Addresses of manufacturers or jobbers who handle 

 molded rubber gloves containing lead, suitable for X-ray work, 

 are desired. 



