610 SCIENCE PROGRESS 



ject, seeing no way of making synthetical rubber commercially 

 possible. 



Even if future research should result in the production of 

 artificial caoutchouc in quantity, it is very doubtful if it could 

 ultimately compete with natural rubber, especially the planta- 

 tion variety, as this most likely could be sold with a fair profit 

 at a price of 3s. or even 25. 6d. per lb. The raw material 

 required for the synthesised product might cost nearly as much. 

 Then again, though the artificial rubber might appear, as far as 

 chemical analysis could show, identical with the natural article, 

 it might be lacking in the essential physical properties. The 

 synthesis of a colloid like caoutchouc, presumably of high 

 molecular weight, is a problem of a different order from that of 

 such comparatively simple crystallisable bodies as vanillin or 

 even indigo. 



However, at the present price of rubber, a synthetic com- 

 mercial rubber of passable physical properties would not only 

 be a boon, but a lucrative discovery. Patents have been taken 

 out, and even companies floated for the production of synthetic 

 rubber, but nothing visible has appeared as yet! 



It is important also here to draw a clear distinction between 

 a true synthetic caoutchouc and the so-called artificial rubbers. 

 These latter are merely substitutes or adulterants, and would 

 be discarded if raw rubber were cheaper. They are prepared 

 chiefly from oils, linseed being considered the best. 



It is, of course, not the purpose of this paper, even if the 

 writer had the necessary knowledge, to deal with the chemistry 

 of caoutchouc. This part of the subject has already received 

 full treatment in the pages of Science Progress. l Suffice it 

 here to say that through the important researches of Prof. 

 Harries 2 attention is now being directed towards the synthesis 

 of caoutchouc from carbohydrates. This investigator has 

 shown good reasons for regarding caoutchouc as related to 

 the pentoses, and so it is suggested that in the plant it may 

 be derived from such sources. 



Concluding Remarks 



This new industry then appears to have a most hopeful 

 future before it. The time, however, has by no means arrived 



1 Pickles, S. S., Science Progress, 1907, 1, 497. 



2 Harries, Ber. Deut. Chem. Ces. 1905, 38, 87 and 1195. 



