DISTILLED OIL OF CAOUTCHOUC. 
341 
ed the attention of chemists to the alteration which oil of 
caoutchouc underwent by the contact with sulphuric acid. 
M. Liebig, {Jlnnalen der Pharm. Oct. 1835,) has thrown 
out the idea that this oil may be changed into eupione by the 
acid; and if this is so, it is probable that the eupione is pro- 
duced by the reaction of the acid employed to extract it, ac- 
cording to the method of M. Reichenbach. It does not ap- 
pear to me probable that the second oil, of which I have 
spoken above, is eupione. When the point of ebullition, 47° 
of this last, is compared with that of the other, which is 225°, 
it is obvious that there must exist a remarkable amount of im- 
purity, even should these liquids be the same. At the same 
time, I must avow, that I have obtained during the past year, a 
certain quantity of a liquid which I regard as impure eupione, 
by treating the products of a distillation of caoutchouc, pro- 
cured myself, with sulphuric acid. But this distillation did 
not afford an oil like that of Mr. Enderby. 
M. Liebig also thinks that the other substances described 
by M. Reichenbach, are only the products of reaction, and do 
not exist in the pitch. But I may be permitted to remark, 
that the presence of creosote is detected in pitch as well as in 
pyroligneous acid, by its odour and by its antiseptic power; 
that paraffine can be purified in a considerable degree by rec- 
tification, and that M. Reichenbach has rendered it probable, 
in his last memoir upon eupione, that this substance can be 
extracted from the tar of oil, by complete rectification, and 
without the addition of any reagent. Be the fact as it may, 
the change produced upon the oil of caoutchouc by sulphuric 
acid, merits the attention of those who are engaged in study- 
ing the empyreumatic substances; without attaching impor- 
tance to it as an example of isomery, the difficulty of purify- 
ing these products, is apparent. 
Journal de Pharmacie. 
