6 ODOROGRAPHIA., 
were made by Margraff and by Elsner *. Coarse pieces of amber, 
reduced to powder and mixed with sand, are distilled in an iron 
retort; the oil which distils over is separated from the fetid liquor 
and succinic acid which accompanies it, and after being rectified 
at a gentle heat with about six times its volume of water, is 
gradually added to and digested with 31 parts by weight of fuming 
nitric acid, artificial cold being employed to prevent any portion 
of the oil being carbonized. An orange-yellow resinous matter 
forms, which, after being carefully dried, is the required product. 
It is also said to be formed by digesting for ten days one ounce of 
fetid animal oil, obtained by distillation, and half au ounce of 
nitric acid, then adding rectified spirit one pint, and digesting for 
a month. 
The crystalline substance now met with in commerce under the 
name of “ artificial musk,’ or “ Musk Baur,” is a trinitro deri- 
vative of butyl-toluene, produced by the action of nitric and 
sulphuric acids upon the hydrocarbon meta-butyl-toluene obtained 
from isobutyl bromide and toluene, and also found in resin-spiritt. 
A great number of homologues and isomerides have been prepared, 
but though many possess a musk-like odour, none have so great a 
technical value; it has therefore been found advisable to carefully 
purify the butyl-toluene for technical purposes. According to the 
English specification of Baur’s Patent (No. 4963, 21 Mar. 1889), 
this “ substitute ” for musk consists of a nitrated hydrocarbon of 
the C,,H,, group, for the formation of which five parts of toluene 
are mixed with one part of butyl bromide, or butyl chloride, or 
butyl iodide. To these may be added gradually, whilst boiling, 
one fifth part of aluminium chloride or aluminium bromide ; this 
results in the development of hydrobromie or hydrochloric or hy- 
driodic acid respectively, and a product of reaction is obtained 
from which, by the action of steam, the hydrocarbon C,,H,, and 
unchanged toluene are distilled. By the admission of steam the 
hydrocarbon is carried along, and may be obtained in a condenser 
as a colourless oil floating on water. The oil, removed and dried 
by means of chloride of calcium, is fractionated, and in this manner 
the necessary hydrocarbon for the production of artificial musk is 
* Journ. fiir praktische Chemie, 1842. 
+ ‘Comptes Rendus de l’Académie,’ cxi. pp. 238-240; Berichte Chem, Ges. 
xxiv. p. 2882; Pharm. J. li. p. 266, 
