696 



THE INDIA RUBBER WORLD 



ISei'tembek 1. 1919. 



treating a solution of rubber with clilurinc, or bromine and 

 chlorine, the rubber is dissolved in benzene or a homolog. 

 Chlorine is passed through the solution until the rubber has 

 taken up approximately twice its weight of chlorine. The pres- 

 ence of catalysis is avoided. The hydrochloric acid produced is 

 removed by heating or neutralized, for example, by ammonia or 

 lime. (H. M. Broadhurst and A. Lamble, Cunard Building, 

 Liverpool ; S. J. Pcachcy. 5 Yew Tree Road, Davenport, Stock- 

 port ; and United Alkali Co., Cunard Building, Liverpool. Brit- 

 ish patent No. 127,481.) 



OTHER CHEMICAL PATENTS. 



THE FRENCH REPUBLIC. 



435,031. Vukaniz.iblc subsUtute ior rubber. J. Flint. 



■t35,l-t8. Rubber compound. E. von Vargyas. 



-;S5,778. Treating rubber and rubber substitutes. General Rubber Co. 



485,/','7. Treating latex preparatory to vulcanization. General Rubber Co. 



l".';.?.:;. (^..gulatm,; rubber or the liU-e. (■.rneral Rubber Co. 



RUBBER DIVISION OF AMERICAN CHEMICAL 

 SOCIETY. 



THE first meeting of the newly organized Rubber Division 

 of the American Chemical Society will be held in Pliiladel- 

 phia, Pennsylvania, September 4 and 5. 



A large attendance is expected and in view of the very in- 

 teresting program that has been provided, the meeting promises 

 to be a most successful one. The following reports and papers 

 will be read ; 



1. Report of tbe Executive Committee. 



2. Report of the Secretary. 



3 R»port of the Fruit Jar-Ring Committee. L. J. Plumb, chairman. 



4. Report of the Committee on Physical Testing. H. E. Simmons. 



5. "A Method of Determining Permanent Set in Rubber Goods." E. 

 L. Davies. 



6 'A New Method for the Determination of Sulphur in Rubber 

 Mixtures." G. D. Kratz. A. H. Flower and Cole Coolidge. 



7. "The Extraction of Rubber Goods." S. W. Epstein and B. L. 



°'8^°'"Thc Theory of Balloon Fabric Protection." John B. Tuttle. 

 9. "The Expansion of Rubber Compounds." C. \\ . Sanderson. 

 10 "Volume Increase o'f Compounded Rubber Under Strain." H. F. 

 Schippel. 



11. "The Determinat! 

 Epstein and B. L. Gonyo. 



12. "The Variability of Crude Rubber." John B. Tuttle. 



13 Symposium on the "Action of Accelerators during Vulcanization." 

 Led by J. H. Scott. 



14. "The Action of Certain Organic Accelerators m the \ ulcanization 

 of Rubber." G. D. Kratz. A. H. Flower and Cole Coolidge. 



15 "Reactions of Accelerators during Vulcanization." C. W. Bedford 

 and Winfield Scott. 



16. "The Effect of Organic Accelerators on the Vulcanization Coeffi- 

 cient." D. F. Cranor. 



17. "liic Ktfect of Compounding Ingredients on the Physical Proper- 

 ties of Rubber." C. Olin North. 



13. "Son.c Methods of Testing the Hardness of Vulcanized Rubber." 



19. Symposium on the "Testina of Pigments." Led by George Oens- 

 lager. Contribution from M. M. Harrison and M. M. Kahn. 



20. "Thi- Manufacture and Use of Crimson Antimony." J. M. Bierer. 



21. "Laboratory Aprons." C. P. Fox. 



22. "The Value of a Library to the Rubber Laboratory." IL E. 

 Simmons. 



of Cellulose in Rubber Goods.' 



S. W. 



FIFTH NATIONAL EXPOSITION OF CHEMICAL INDUSTRIES. 



The Fifth National Exposition of Chemical Industries will 

 be held at Chicago, Illinois. Coliseum and First Regiment Arm- 

 ory, the week of September 22, 1919. 



This will be the largest gathering of chemists in the United 

 States since the war. The leading engineering and metallurgi- 

 cal societies of the country plan to hold meetings at which many 

 interesting and important papers will be presented. There will 

 be many new exhibitors in addition to all the former ones, 

 covering the entire rteld of chemical industries. 



"Crude Rubber and Compouxdixg Txgrediexts" -\xd "Rub- 

 R Machinery," by Henry C. Pearson, should be in the library 

 every progressive rubber man. 



LABORATORY APPARATUS. 



QUIET EVAPORATION. 



'T'he tendency ok solutions in beakers or flasks to bump on a 

 *■ hot plale may be obviated by substituting an oil bath for the 

 plate. The containers should be iinmersed so that the oil of 

 the bath will be at a higher level than that of the solution to 

 be heated. The solution will thus be heated evenly and boil 

 quietly as in the case of sleam-jackcted kettles. — ("The Chemist- 

 Analyst.") 



PINCH CLAMP. 



Tlic Day pincli clamp, shown in ihc illustration, can be placed 

 on rubber tubing from the side 

 without disconnecting the ap- 

 paratus. It has a firm, strong 

 grip, sufficient for all tubing up 

 to Ji-inch in diameter. The 

 thumb grips are large and well 

 Day Pinch Clamp. '°"'''«' ^°^ efTecliveness. This is 



said to be the only pinch clamp 

 on the market that can be fastened*on tubing without disconnect- 

 ing the apparatus of which it is a part. (Central Scientific Co., 

 460 F:ast Ohio street. Chicago, Illinois.) 



WEIGHING BURETTE. 



.\ siiriple weighing burette has been devised to avoid certain 

 of the disadvantages of ordinary burettes, such as inaccuracy 

 of bore, temperature variation, drainage, and difficulty of ac- 

 curate reading. This instrument obviates all 

 corrections and allows nearly as rapid work 

 as the ordinary style, with accuracy limited 

 only by the sensitiveness of the end-point. 



To use the burette, turn up with the cock 

 closed, so that the capillary is over the titrating 

 vessel, and allow the heat of the hand to force 

 the standard solution into the capillary. Then 

 when the cock is opened the liquid will flow 

 freely, and there will be no danger of loss 

 through the cock. When near the end-point, 

 the cock may be closed and the solution forced 

 in drops by the heat of the hand. 



A predetermined quantity of solution cannot be delivered with- 

 out repeated weighings, but a little practice will enable the user 

 to estimate the desired quantity within a few per cent. A 100-cc. 

 flask with rubber stopper, cock, and capillary, weighs about 40 

 grams.— ("The Journal of Industrial and Engineering Chem- 

 istry," July, 1919.) 



REMOVING PLUGS FROM STOP-COCKS. 



\n cffictive device for removins plugs from glass stop-cocks 

 is here illustrated and de- 

 scribed. 



The common method of 

 removing the stuck plug is to 

 hammer gently on a sinall 

 piece of wood placed on the 

 plug, often resulting in the 

 barrel being cracked, the 

 plug chipped and breakage 

 of important parts of com- 

 plex apparatus. If, however. 



Method of Removing Stop- " '^e steady pressure of an or- 



CocK Plugs. ^''"^--y ^''^^ '' ^''"^'"^ °" ^^^ 



plug with the glass in contact 



with nothing but wood, the plug can easily be removed without 



damaging either barrel or plug. — ("The Journal of Industrial 



and Engineering Chemistry," May, 1919.) 



