and Magazine of the Ceylon Agricultural Society.— July, 1912. 



95 



The material in question is not rubber, but 

 a homologue of rubber, and should be known 

 by another name. " Homo-rubber" is bar- 

 baric in structure, but it may serve until a 

 better name for general use has been devised_ 



Wyndham R. Dunstan, f.r.s. 

 Imperial Institute, S.W., June 19. 



Further Points to be Determined. 



Mr. Bertram Blount, 

 who was present at the reading of Professor 

 Perkin's paper on Mouday, in discussing the 

 situation with a Morning Post representative 

 yesterday, said: "The large attendance of chem- 

 ists at the meeting and the character of the 

 discussion which followed on Monday both show 

 how keenly the interest of English chemists 

 has been aroused in Professor Perkin'3 announce- 

 ment. The record of the work done is elegant, 

 both from tho standpoints of the chemist and 

 of the bacteriologist. The chemiets may con- 

 gratulate themselves on the discovery that the 

 addition of slight quantities of sodium is able 

 to transform isoprene, or rather, in the present 

 instance, butanediene into rubber or a substance 

 closely resembling it ; and the bacteriologists 

 have equal cause for pride in having found a 

 bacterium that is capable of transforming sac- 

 charified starch into acetone and butyl alcohol. 

 I must confess to a feeling of surprise at the 

 latter result. Butyl alcohol contains four carbon 

 atoms, whereas ethyl alcohol, the ordinary sub- 

 stance produced as a result of fermentation, has 

 only two. Now the greater the number of carbon 

 atoms contained in an alcohol, the stronger is 

 its toxic effect, and one would have expected 

 that the bacterium effecting the change would 

 have been overcome by the products of its act- 

 ivity loDg before it had been able to complete 

 its work. One can only say that it proves itself 

 to be of a most hardy type, and that Professor 

 Fernbach deserves all praise for his work." 



Attitude of the Planters. 



''Considering the announcement more gene- 

 rally and criticising it, I feel bound to say 

 that there are a few points on which we require 

 further information before we can make any- 

 thing in the nature of a dogmatic statement. 

 It will be noticed that in his process Professor 

 Perkin derives his rubber-like substance from a 

 body with four carbon atoms, whereas isoprene, 

 from which rubber has hitherto been synthe- 

 sised, and rubber itself both have five carbon 

 atoms, or in the case of rubber a multiple of 

 five carbon atoms. One wants to know whether 

 the rubbery substance derived from the four 

 carbon body will have the same actual com- 

 mercial uses that the naturally grown substance 

 possesses. Again, in considering the effect of 

 the discovery on a great industry, it must be 

 borne in mind that the rubber planters are a 

 powerful organisation and will not probably 

 be caught napping, as the indigo planters were 

 about a decade ago. No one in the city, at 

 any rate, knows the real price of rubber. We 

 have seen it fluctuate from two to twelve 

 shillings, but neither figure has been the natural 

 price of the substance. The effect which the 



rtificial rubber will produce depends, not only 



on the price at which it can be produced, but 

 also on the true economic pi ice of naturally 

 grown rubber ; that is to say, on the price at 

 which it will pay to grow and sell the natural 

 rubber. 



"A further point to remembe-ed is the source 

 from which the rubber is to be obtained, starch. 

 Starch is not a substance that can be got out 

 of the earth like coal or petroleum, but one 

 which has to be grown, as rubber has to be 

 grown. This point whs raised at the Society of 

 Chemical Industry. It is partly coat by :he state- 

 ment that starch in the form of tube's of one 

 kind or another can be grown practically any- 

 where and in very large bulk per acre, but 

 the fact has to be*ememberel that the raw 

 material of synthetic rubber is a substance that 

 requires to be raised at consi derable expense. 

 An experiment of considerable interest would be 

 to polymerise both isoprene and butauediene 

 with sodium and compare the two products 

 thus obtained with each other and with natural 

 rubber. Considering the fact that natural rubber 

 is not a pure substance, but contains a consider- 

 able percentage of resins, mrch as turpentine, 

 for instance, does, i I; is a bold statement to say 

 categorically that rubber is polymerised iso- 

 prene, though the evidence may be admitted to 

 point in that direction. 



11 To prevent misconception, I should like to 

 add," Mr Blount continued, "that these criti- 

 cisms take nothing away from the extreme ele- 

 gance of the process which Professor Perkin do- 

 scribed to us on Monday night. At the first 

 announcement of such a process there are bound 

 to be a number of suoh points as I have indica- 

 ted arising, and i ; ine only can show how far 

 the new process is abl< to hold its own against 

 the severe test of commercial competition. In 

 any case, the paper wi!l aiways be regarded as 

 a record oi great scientific achievement." — M. 



Post, June 20. 



Probable east and selling Price of Synthetic 

 Rubber. 



(To the Editor, " Financial Times.") 

 Sir, — It has been obvious during the last few 

 days taat P.'of 3 is. r Perkin's statements as to 

 these points hj,/a nob been clearly understood. 

 As organisers of tile research group represented 

 by Professor Perkin it the lecture to the Society 

 of Chemical Industry on Monday night last, we 

 make the following stateconts : — 



The process for the manjfacture of synthetic 

 rubber employs st^rch-cortaining substances as 

 the raw materials. The search in maize costs 

 on the average less than Id per lb. Only five 

 operations are required to convert the starch 

 into rubber, and Siiese aro known to proceed 

 easily giving good yields. The only other ma- 

 terials required ar , common salt, costing, say, 

 30s per ton ; lime, costing, say, 30s per ton ; 

 coal costing, say, 15s per ion. The total cost 

 for the raw n;aterials to make 1 lb of 

 rubber does not oxceed 2d. With such cheap 

 and plentiful ra-v mater-als it is obvious 

 that there is a urge margin for manufac- 

 turing expenses if Is per lu is taken as the cost 

 price. In fact, it is probable that when exper- 

 ience has enabled the large scale plant to be 



