THE ODOUR OF ROSE. 59 
Millon and patented by Ferrand, his co-worker (Brevet 22404) *. 
The flowers were packed in a displacement-apparatus and exhausted 
by disulphide of carbon or ether: the odorous principle was then 
isolated by evaporating the solvent. This process was found im- 
practicable on a large scale owing to the danger of manipulating 
large quantities of the solvent in open vessels ; it was also found 
that the residuary resinous matter retained the odour of the di- 
sulphide of carbon or of the ether, which could not be removed 
without destroying the odorous principle. 
In 1862 the experiments were repeated by Piver, who endeavoured 
to remove the last traces of the solvent by washing the product 
with a weak alkaline solution and so leave the perfume pure + ; 
but that idea had already been patented by Deiss of Marseilles f, 
and does not appear to have proved successful, probably owing to 
the great susceptibility of such delicate perfumes to deterioration 
or alteration by contact with alkalies. 
Patents were also taken out by Lemettais & Bonniére of Rouen 
for the extraction of the odours of spices and living plants by 
disulphide of carbon, and rectification by alkalies and salts of 
lead §. The processes of Ville || and of Hirtzel{, which were 
modifications of Millon’s process, the former employing chloro- 
form and the latter petroleum ether, could not stand the test of 
practical working for similar reasons. 
A method has been recommended by Millon for the purification 
of disulphide of carbon; it is as follows :—The disulphide is first 
washed several times with water and then introduced into a large 
retort with a quantity of quicklime. After 24 hours’ contact the 
disulphide is distilled from the lime and received in a flask con- 
taining a large quantity of copper turnings which have been 
previously calcined to remove organic matters and then reduced 
by heating in a current of hydrogen. The lime from which the 
disulphide has been distilled is deeply coloured and resembles crude 
soda-ash in appearance. The disulphide of carbon thus purified 
has an ethereal odour, which, if not actually agreeable, is quite dif- 
ferent from the offensive smell of commercial disulphide. It was 
with disulphide of carbon thus purified that Millon and Commaille 
* Journ. de Pharm. et de Chim. xxx. pp. 281 & 407. 
+ Rep. de Chimie, iv. p. 286. ¢ Brevet 54126. 
§ Brevet 55499, 1858. || Brevet 47285, 1860, 
{| Brevet 61486, 1864. 
