5A ODOROGRAPHIA. 
the grease in the seventh compartment, already almost saturated, 
takes up the superabundance of perfume from the fresh flowers, 
whereas it would not be able to absorb the last traces from the 
flowers which have been nearly exhausted by passing on to the 
first basket. 
The method of making the spirituous extract consists in beating 
up the perfumed pommade with alcohol. The pommade is first 
granulated or passed through a macaroni press (what is called in 
London a “ Piping press”), so as to bring it into a fine state of 
division and offer a large surface to be acted upon by the strong 
spirit (80 or 90 per cent. alcohol) with which it is agitated. This 
takes place in large drum-shaped copper cylinders, standing upright, 
and provided with powerful stirrers which revolve in opposite 
directions, the motion being given by cog-wheels connected by a 
band with the main shafting. About 12 gallons of alcohol is 
first poured in, the pommade is then introduced, and the lid 
bolted on; this is rendered air-tight by an india-rubber washer. 
The stirrers are then set in motion, and in a little time the con- 
tents are thoroughly blended and form a creamy mass. The 
stirring is continued for many hours, at the end of which time 
the contents are allowed to remain quiescent. The fat subsides 
and the alcohol is drawn off and passed through tubes surrounded 
with iced water, which solidifies and separates the remainder of 
the fat mechanically held in solution in the alcohol. The same 
pommade is subsequently washed with one or two more charges of 
spirit, by which time all the perfume is absorbed. The grease is 
now free from all scent, but by this process has acquired a great 
tendency to become rancid. It would appear that decomposition of 
the fat commences during the long kneading with alcohol in con- 
tact with air, although the drums in which the extracts are made 
are kept well closed. The fat is lastly placed in a steam-jacketed 
still to recover the alcohol mechanically mixed with it; but it is 
not again employed in any part of the factory. It is used by 
toilet-soap manufacturers, to whom it is very valuable on account 
of its great purity. Another sort of “agitator” for this purpose 
was invented by Piver; it seems particularly suitable for use with 
the perfumed oil; the contents of the vessels being subjected to a 
duplicated movement by reason of the vessels not being fixed axially 
in the same plane of rotation as that of the machine; by this 
arrangement the extremities of each cylinder are alternately high 
