THE INDIA RUBBER WORLD 



[March 1, 1920. 



lined with mix- 

 The results for 



In Table IV we have given a lew hgure: 

 tures which also contained a mineral siibsta 

 these mixtures require no comment. 

 SUMMARY. 



Briefly, our method, as herein described, ditTers from others 

 which cUminate subsequent fusion with sodium carbonate-potas- 

 sium nitrate mixture, chiefly in the introduction of a process 

 whereby the products of the initial oxidation are "baked" in the 

 presence of zinc oxide. By this means, complete oxidation and 

 the expulsion of oxides of nitrogen are insured. We have found 

 it to be accurate to within 0.1 per cent as compared with the 

 method of Waters and Tutllc. A further advantage which in- 

 creases both the accuracy of the method and the rapidity of its 

 manipulation is that it does not require the transference of the 

 contents of the flask in which the determination is made until 

 the precipitation of the barium sulphate is to be effected. 



We have found that from thirty to fifty determinations can 

 easily be made, by our method, by one man in a week's time. 

 Incidentally, the quantity of nitric acid required is small, in com- 

 parison with other methods. 



In conclusion, we strongly recoinmend the determination and 

 subtraction of a blank, to allow for sulphur in the combined re- 

 agents employed". This applies, not only to our own method, but, 

 likewise, to any other inethod as well. 



In view of the results recorded above, we are warranted in 

 drawing ihe following conclusions : 



CONCLUSIONS. 



1. It is possible to obtain complete oxidation by our method 

 of procedure, which involves baking the residue in the presence 

 of zinc oxide. 



2. The results obtained by our method for combined sul- 

 phur (as compared with those obtained by the method of Waters 

 and Tuttle), or for total sulphur (as compared with the 

 added to the mixture), are accurate to within 0.1 per cent. 



3. The rapidity and accuracy with which sulphur del 

 tions can be made by our method recommends its use for routine 

 work in the rubber laboratory. 



*® Our experience 



to emphasize this point. It is possible that the subtraction of a blank for the 

 reagents used would have lowered considerably the figure (0.18 per cent) 

 obtained by Fol and Van Heurn ("Communications of the Netherlands Gov- 

 ernment Institute for .Advising the Rubber Trade and the Rubber Industry," 

 Part VI, page 184) for the unextractable sulphur in an unvulcanized mixture. 

 With the best obtainable reagents, blanks will run from 0.05 to 0.15 per 

 cent, according to the method and reagents employed. On repeating the work 

 of Fol and Van Heurn, wherein we extracted the unvulcanized mixture with 

 acetone for twenty-four hours, we obtained a combined sulphur of 0.067 

 per cent after the subtraction of a blank for the re-agents. 



PLANTATION RUBBER, A FORECAST. 



AssUMi.NU that the acreage planted in rubber will increase 

 at the rate of increase of the years since the war began, 

 which in round numbers is something under 150,000 acres yearly 

 —in the four previous years it was nearly 300,000 acres a year— 

 the average under plantation rubber for 1919 should be 2,900,000 

 and for 1920 about 3,050,000 acres. It is possible that falling 

 prices may check extension in the countries in British hands, 

 but any such effort will be offset by increased cultivation in the 

 Dutch possessions and in the lands where experimentation with 

 rubber culture, and, above all, with Hcvca, has been going on 

 scientifically — Borneo, New Guinea, the Philippines, Cochin 

 China and East and West -Africa, British, French and Belgian. 

 There is an effort to restrict in some degree the indiscrimi- 

 nate collection of rubber, for many reasons and in many ways : 

 by planting fewer trees to the acre and farther apart; by tap- 

 ping at longer intervals and more sparingly in accordance with 

 the theories of scientific experts, who attribute diseases and 

 other mishaps to the methods of tapping, so that in some places 

 trees are tapped only in alternate years or less frequently, in 



oiluTs (inly on some fraction of the circumference, in all some- 

 what less recklessly and profusely ; by arbitrarily abstaining from 

 collecting a portion of the crop in order that the stock on the 

 market may be diminished and prices be kept higher in conse- 

 quence. 



This is offset by the fact that only the first trees planted have 

 come to full maturity, and that the younger trees planted a score 

 of years ago are maturing by hundreds of thousands of acres 

 yearly, each tree able to yield more latex every year. The full 

 impact of the planting begun in Malaya twenty-five years ago 

 has not been felt, and the millions of trees planted in other suit- 

 able lands also have yet to come to full maturity. The annual 

 supply of crude rubber must increase largely from natural causes 

 even if not a single new tree were planted. 



The increased demand for rubber in the United States is likely 

 to continue for years to come. The lOO.OCX) tons called for in 

 1915 had increased 50 per cent in 1918 and had gone nearly to 

 the 200,000-ton mark in 1919. While the building of automo- 

 biles may reach its limit within a few years, it is not likely that 

 their use will be checked and a steady supply of tires must be 

 inevitably provided for them. 



While the rubber supply from Brazil, Africa, and other dis- 

 tricts may be looked upon as likely to stay at (30,000 tons at the 

 most, unless modern and improved methods are applied, the 

 production of plantation rubber in the Far East can easily be 

 increased by 50.000 tons yearly, if the demand calls for that 

 amount at a fair price. In all probability the eastern plantations 

 could soon send in much more than that amount of rubber, if 

 any emergency should demand it, unless some disaster to the 

 rubber culture should intervene, like the boll weevil devastation 

 of Sea Island cotton. 



AcKE^\GE, FroDL' 



World's Peodoction. 



925 



•Estimated. 

 DR. SCHAEFFER VICE-PRESIDENT EAGLE-PICHER LEAD CO. 



Dr. John A. Schaeffer, chief chemist and metallurgist of the 

 Eagle-Picher Lead Co., at Joplin, Missouri, for nine years past, 

 was made a vice-president of the company at the annual meet- 

 ing held in Cincinnati, February 17, with headquarters in St. 

 Louis. He will have, in addition to his scientific duties, full 

 charge of all operations of the company's St. Louis district, which 

 includes the plant at Hillsboro, Illinois, where zinc oxide will be 

 manufactured, and the plant of the Hammar Brothers White 

 Lead Co., recently acquired by the Eagle-Picher company. 



Before joining the company Dr. Schaeflfer was instructor in 

 chemistry at the Carnegie Institute of Technology at Pittsburgh, 

 Pennsylvania; he is a member of the American Institute of Chem- 

 ical Engineers and the American Chemical Society. R. E. Mc- 

 Cormack, formerly purchasing agent and assistant traffic man- 

 ager at Joplin, will be his assistant. The offices of the Eagle- 

 Picher Lead Co. are now in the Railway Exchange Building, 

 St. Louis, Missouri. 



