SEPTEMBEa 1, 1914.] 



THE INDIA RUBBER WORLD 



649 



market. As I have said, any disputes arc settled by arbitration. 



The development of the Mid Eastern markets would be wel- 

 come for more reasons than one, but unless or until they can 

 give the buyer the same security and protection afforded in 

 London, their growth will be checked. 



No doubt the idea of shipping direct arose out of the sus- 

 picion that the American consumer is not receiving fair treat- 

 ment in London. Although I have endeavored to show that this 

 suspicion has little foundation in fact, there is no obvious rea- 

 son why the buyer should not have supplies sent direct without 

 intermediate handling in London. More especially would this 

 apply in the case of forward contracts made with plantation 

 companies. Assuming that the buyer trades in such a way as 

 to avail himself of the protection afforded by the London mar- 

 ket, the consignments would be sent direct from the plantation 

 to \ew York, and samples despatched at the same time to the 

 London broker. In the event of a dispute, the broker would 

 su1)mit the samples to the Rubber Trades .-\ssociation, and the 

 matter would be settled with the minimum of trouble. 



It has been shown, then, that while there is no foundation for 

 the statement that in the handling of plantation rubber in Lon- 

 don the American consumer necessarily suffers, it is unfor- 

 tunately true that consignments are more mi.xed than is desir- 

 able. ' But much of this is avoidable. If an American buyer 

 wants five tons of fair average quality sheet, for example, he 

 should give a list of the marks he knows will suit him. The 

 dealer will then buy those marks. If, on the other hand, an or- 

 der merely states five tons of smoked sheet, without further 

 specification, the odds are that a mi.xed lot will be received. At 

 present it is sometimes impossible to supply a norder for, say, 

 twenty tons of a particular mark if the grade required is not 

 one of the standard qualities. On the other hand, an order for 

 fifty tons or more of fine pale crepe can be executed without 

 much difficulty. It is not a question of unfair treatment. The 

 great variety of types produced and tlie mushroom growth of 

 the industry are partly responsible for such troulile as arises. 

 A better understanding of the capacity of the industry and a 

 closer acquaintance with market conditions would remove much 

 of the misapprehension that exists. Xothing but good can come 

 of ventilating the position in every possible way, and if any of 

 your readers care to express their views or to put questions, I 

 shall be pleased to go further into matters through the medium 

 of The Indi.\ RrnBER W'ori.h 



WHAT THE RUBBER CHEMISTS ARE DOING. 



THEKL has recently been published by permission of the 

 Bureau of Standards at Washington a method for the 

 direct determination of rubber by combustion of the nitrosite 

 and the determination of the carbon. 



The action of sulphur trioxide on rubber was noticed very 

 early, as Harries in 1901' described it, but all authorities agree 

 that it seems to be of varying composition. 



The proposed method seeks to avoid the difficulties which 

 have been encountered in working previously with these com- 

 pounds by determining the carbon content, which is said to 

 remain constant or at least contain all the carbon of the rubber 

 sample. 



"The procedure in brief consists in first forming the nitrosite 

 of rubber by the action of nitrogen trioxide gas upon a finely 

 ground and acetone-extracted sample of the rubber suspended 

 in chloroform. After the completion of the action the insoluble 

 nitrosite. fillers, etc., arc filtered from the chloroform and the 

 nitrosite is dissolved in acetone; the suspension of finely divided 

 mineral matter is then allowed to settle out or is thrown down 

 with the centrifuge. .An aliquot portion of the solution is trans- 

 ferred with a pipette into a small flask and its volume reduced 

 by evaporation to a few centimeters. This small volume of the 

 acetone solution of the nitrosite is now transferred with the 

 help of ethyl acetate to a porcelain boat containing alundum, 

 and after the acetone and the ethyl acetate have been expelled 

 by warming the boat for several hours in the drying oven 

 the nitrosite is burned in a current of oxygen, and the carbon 

 dioxide formed is absorbed in soda lime and weighed.'' 



The method proposed is to grind a sample to 20 Mesh if 

 possible and weigh out Vz gram and extract with acetone in a 

 Wiley or Cottle extractor. Transfer to a 50 c.c. flask and 

 dissolve or swell in 40 c.c. of chloroform. Nitrogen trioxide 

 is made from arsenic trioxide with 1.3 sp. gr. nitric acid, and 

 this is passed through the rubber solution in chloroform kept 

 cool by immersing the flask in water. .A deep green color shows 

 when enough has been used. 



Filter the chloroform solution through a gooch and wash with 

 chloroform and place the asbestos mat with nitrosite in a 75 c.c. 

 beaker, dissolve in acetone and pour into the original graduated 

 flask, make up to mark and settle and take out 25 c.c, and 

 put in criynniyer and evaporate to small bulk and pour into 



Apparatus kor thb Direct Dbtsrminati 



TRADE FACILITATED BY NEW SHIPPING BILL. 



With the passage of the new shipping bill the fleet of freight 

 vessels owned by W. R. Grace & Co., importers, numbering ten 

 and having a total tonnage of 50.000 tons, will be operated un- 

 der the American flag. Most of these vessels are now in the 

 South .'\merican trade, while four more are being built for the 

 company for the Panama canal trade. It is also expected that 

 the Standard Oil Co., now a fleet of 70 tank steamers, and the 

 United Fruit Co. with 25 vessels floating the British flag, will 

 join the .Xmerican shipping contingent as soon as the necessary 

 steps can be taken. 



ON OP Rubber by thb Combustion Method 



a small boat two-lhirus full of alundum. Rinse with ethyl 

 acetate, dry and place in the combustion tube. 



As shown by the illustration herewith, the combustion tube is 

 a Morse and Taylor tube with an electrically heated platinum 

 spiral wire for a catalyzer." 



This is heated electrically by a nichrome coil on the outside 

 insulated with asbestos and movable along the tube. 



Otherwise this is about the usual combustion train as or- 



^Berichtc, 1901, vol. 34, p. 2991, and Journal Society Chemical Industry, 

 1901, p. 1123. 



»E. & A. Cat. Xo. 2194. 



