730 



THE INDIA RUBBER WORLD 



July 1, 1921 



be required as original equipment for the 1921 production of some 

 1,750.000 passenger cars and trucks, making a total visible demand 

 lor 39,239,532 tires. That this total appears to be a conservative 

 estimate is indicated by adding 22 per cent — the increase in motor 

 car registration for the year 1920 — to the estimated 1920 tire con- 

 sumption amounting to 34,065.000 tires, as shown in The India 

 RvBBER World of March, 1921, page 410, which indicates a de- 

 mand for 39,559,300 tires. Thus, despite the temporary sales 

 depression of the spring and early summer, the future of the tire 

 ir.dustrv cannot be viewed with other than assurance. 



A PNEUMATIC TREEING MACHINE 



This machine is a great improvement on the machines using 

 wooden feet, as these feet are made of flexible rubber, covered 

 by leather and supported by a wooden back or leg. The rubber 

 feet are inflated with compressed air supplied by a small air 

 compressor and air tank. The shoe to be ironed is placed on 

 the tree, air admitted, and the rubber foot encased in the leather 

 casing expands to fill uniformly the shape of the last. With the 

 release of the air the foot collapses and the shoe is readily 

 removed. This machine does not require a change of feet for 

 every size of shoe to be ironed, two or three shoes being treed 

 on one size foot. — W. J. Young Machinery Co., 416 Union street, 

 Lj-nn, Massachusetts. 



RUBBER ACCELERATOR SERVICE LABORATORIES 



AT its Perth .Amboy plant, the Roessler & Hasslacher Chemical 

 Co. maintains what might be termed an accelerator service 

 laboratory. A number of years ago when the use of accelerators 

 was in its infancy, this company prepared to secure exact informa- 

 tion as to the action of its accelerators in various stocks and under 

 widely varying conditions. It therefore engaged the services of 

 an experienced rubber technologist and equipped a modern rub- 

 ber laboratory for this purpose. 



The laboratorv- equipment, part of which is shown in the accom- 

 panying illustrations, was so selected that all factory conditions of 

 vulcanization could be duplicated. With this equipment it ha^ 

 completed elaborate series of tests on its various accelerators 

 in standard-type formulas in comparison with many other well- 

 known accelerating materials, and with some not so well known. 

 The type formulas used were so selected that the effect produced 

 by larpe and small amounts of active inorganic materials could 

 be determined. As a result of these comprehensive tests, the 



MixiN'c Mill, Calender and Vulcanizers 



company is able to give rubber manufacturers exact information 

 as to the proper utilization of its accelerators under widely vary- 

 ing conditions. 



Many rubber manufacturers have availed themselves of the 

 service offered and have sent type, or actual formulas in which 

 it is desired to use an accelerator. When such formulas are re- 

 ceived, varying amounts of accelerator are added and the stock 



is given a range of cures for each percentage to determine the 

 optimum cure for factory operation. The usual tests, tensile, 

 stretch, and permanent elongation, are recorded for each cure 

 and the results are submitted to the rubber manufacturer. 



During the four years of its operation this laboratory has ac- 

 cumulated a vast amount of accelerator information and has made 

 practical tests for many rubber manufacturers covering stocks 



Compounding Bench, Vulcanizing Press and Tensile 

 Machine 



varying from those for rubber bands to those for solid truck 

 tires, many of which have resulted in a direct benefit to the rub- 

 ber manufacturers. This service is offered gratis to all present 

 and prospective accelerator users regardless of the magnitude of 

 their output. 



INTERESTING LETTERS FROM OUR READERS 



RECEIVED THE DESIRED INFORMATION 



To the Editor : 



r\EAR Sir: We wish to thank you for your letter of May 19 

 ^-^ and for the information contained therein. This information 

 i? just what we were anxious to get. 



I have also taken steps to have this company subscribe to The 

 India Rubber World in the very near future. I feel that you will 

 undoubtedly be able to help us a great deal from time to time both 

 through the periodical which you publish and by direct answer 

 to our questions. It is very gratifying indeed to find one who is 

 willing to give the right kind of information. 



We shall look forward to receiving the sample copy which you 

 have sent to us. Inquirer. 



This letter is published to call our readers' attention to the 

 opportunity afforded by our Information Department for reliable 

 rubber information. — The Editor. 



INTERESTED IN SELECTING WORKMEN BY PSYCHIATRY 



To THE Editor : 



r^EAR Sir: Is it possible to get full details as to method em- 

 ■'-^ ployed, questions, etc., by Lieutenant \. W. Stearns, M. D., 

 in selecting workmen by psychiatry as mentioned in your issue of 

 May 1, 1921, page 554? 



Such information would be of real value to me. 



Alameda, California. A Reader. 



Lieutenant A. W. Stearns is a resident of Billerica, Massachu- 

 setts, and I am sure would be very glad to be put in touch with 

 you. — The Editor. 



AMERICAN TIRE TRADE IN BRAZIL 



Among exports from the United States to Brazil, during 1920, 

 may be mentioned tires, which in that year amounted to $1,965,201 

 as compared with $1,018,055 the year before. This is an increase 

 of about 93 per cent. 



