March 1, 1921 



THE INDIA RUBBER WORLD 



431 



purpose for which the article is to be used, and the effect of the 

 various constituents on the service. If the purpose of the analysis 

 is to determine whether or not material complies with specifica- 

 tions, then the latter should include the methods by which the 

 material is to be analyzed, and if it does not, the methods should 

 be known to anyone who attempts to decide whether or not the 

 terms of specifications have been met. In other words, the results 

 of analyses of rubber compounds are inseparable from the meth- 

 ods by which they were obtained. 



DIRECT DETEJIMINATION OF RUBBER BY NITROSITE METHOD 



A discussion on the direct determination of india rubber by the 

 nitrosite method, by John B. Tuttle and Louis Yurow, has been 

 published as No. 145 of the Technologic Papers of the U. S'. 

 Bureau of Standards. 



The method, which was reviewed in The India Rubber World, 

 October 1, 1917, page 17, is adapted to the analysis of vulcanized 

 cotnpounds containing reclaimed rubber, lampblack, bituminous 

 substances and oil substitutes. It does not attempt to discriminate 

 between new and reclaimed rubber and the authors state that so 

 far as they know there is no quantitative method today which 

 will determine the percentage of either kind in a mixture of the 

 two. Their method gives merely the total of the two kinds, and 

 the average qualify must be determined by means of the usual 

 mechanical tests of tensile strength, elongation, permanent set, etc. 



CHEMICAL PATENTS 



THE UNITED STATES 



PROCESS OF VULC.^NIZ.VTION OF RUBBER IN WHICH AN ADDITION OF 

 dichloranilin is made to the substance to be vulcanized prior 

 to the vulcanization step. — Carl R. De Long, Washington, D. C, 

 and Warren Neal Watson, Auburn, Maine. United States patent 

 No. 1,364,732. 



THE DOMINION OF CANADA 



Vulcanizing Rubber. A process of vulcanizing articles con- 

 sisting in maintaining a chamber filled with steam at substantially 

 atmospheric pressure and substantially excluding air from the 

 articles contained in the chamber, and superheating the steam 

 to effect vulcanization. — The Canadian Consolidated Rubber Co., 

 Limited, Montreal, Quebec, Canada, assignee of Willis A. Gibbons, 

 Pelham Manor, New York, U. S. A. Canadian patent No. 207,221. 



Vulcanized Caoutchouc, Process and Product in which 

 caoutchouc, zinc oxide, a vulcanizing agent and an aryl substituted 

 thiourea accelerator having an alkyl group in ortho position, are 

 mixed and subsequently vulcanized. — The Goodyear Tire & Rub- 

 ber Co., assignee of Winfield Scott, both of Akron, Ohio, U. S. 

 A. Canadian patent No. 207,718. 



Process of Producing Vulcanized Caoutchouc which com- 

 prises incorporating into rubber the products resulting from the 

 decomposition of a proteid by means of an aqueous solution of 

 an alkaline carbonate. — The Goodyear Tire & Rubber Co., as- 

 signee of Clayton W. Bedford, both of .-Xkron, Ohio, U. S. A. 

 Canadian patent No. 207,719. 



Method of Vulcanizing Caoutchouc consisting in reacting 

 upon paranitroso-dimethyl-aniline in solution in an inactive neu- 

 tral solvent with hydrogen sulphide, incorporating a small per- 

 centage of the resultant base into a caoutchouc mi.xture and heat- 

 ing with a vulcanizing agent. — The Goodyear Tire & Rubber Co., 

 assignee of Clayton W. Bedford and Robert L. Sibley, coinvent- 

 ors, all of Akron, Ohio, U. S. A. Canadian patent No. 207,982. 



Manufacture of Thiocarbanimdes and Vulcanization of 

 caoutchouc. The method of producing a substituted thiourea 

 which consists in carrying out the reaction between aniline and 

 carbon bisulphide in the presence of paranitroso-dimethyl-aniline. 

 In the art of vulcanizing caoutchouc the incorporating the above 



resultant mixture of substituted thiourea into the caoutchouc mix 

 and heating the same with a vulcanizing agent to effect vulcaniza- 

 tion. — The Goodyear Tire & Rubber Co., assignee of Clayton W. 

 Bedford and Robert Sibley, coinventors, all of Akron, Ohio, 

 U. S. A. Canadian patent No. 207,983. 



Compounding Rubber Products consisting in first forming 

 an emulsion of water, a gel-forming proteid, oil and gas-black, in- 

 corporating the same into the rubber and evaporating out the 

 moisture from the mixed product previous to vulcanization. — 

 The Goodyear Tire & Rubber Co., assignee of Robert C. H-artong, 

 both of Akron, Ohio, U. S. A. Canadian patent No. 207,984. 



LABORATORY APPARATUS 



TEST-TUBE HOLDEJl 



SOME reformed chemist with an inventive turn has found that his 

 poker chip holder lends itself for easy conversion into a test- 

 tube rack for the laboratory. 



An old discarded poker chip holder 

 can be utilized to good advantage, as 

 shown in the illustration, for holding 

 extra test-tubes. For further conven- 

 ience, a round board may be fitted to 

 the bottom and, with spindle at- 

 tached, be arranged to revolve upon 

 a base. Such a holder will take care 

 of several test-tubes of varying diam- 

 eters and prove a convenient labo- 

 ratory utility. — Popular Science 

 Monthly, New York. Handy Test-Tube Rack 



FOUR-HEAT ELECTRIC DISK STOVE 



The illustration shows a very convenient electric disk stove 

 newly placed on the market. It is adapted for laboratory use as 

 well as for culinary purposes. It may be regulated for four 



different degrees of heat- 

 ing by placing the regu- 

 lating plug in different 

 positions. The stove con- 

 tains two heating coils 

 which are connected to 

 the three terminals. The 

 top is made of aluminum 

 and the stove sets upon a metal deck provided with fiber rests 

 for protecting the table. — The Waage Electric Co., Inc., 12 South 

 Jefferson street, Chicago, Illinois. 



Electric Labor.\tory Stove 



LABORATORY ENAMEX 



An enamel for use on the walls and furniture of laboratories 

 should be white, adhere perfectly and be washable with either 

 hot or cold water. Such an enamel is to be had and the makers 

 claim, in addition to the above qualities, that it is proof against 

 the action of sulphuretted hydrogen, acid and alkali fumes and 

 chemicals. — Toch Brothers, 320 Fifth avenue. New York. 



BARIUM SULPHATE IN SOUTH AFRICA 



Samples of barium sulphate produced by a firm near Johannes- 

 burg, South Africa, have been transmitted by the American consul 

 in that district to the Bureau of Foreign and Domestic Com- 

 merce, Washington, D. C. The firm states that it has a fair 

 deposit of this material and is prepared to deliver it in reasonable 

 quantities f. o. b. steamer at Cape Town. The sample can be 

 inspected by referring to file No. 20,945, and the name of the firm 

 desiring to market the material will be sent by the Bureau or its 

 district and cooperative offices by referring to file No. B E — 6011. 



