LAURUS CAMPHORA. 219 
action of the fire, and an equal degree of heat kept up ; great care 
IS taken during this process to prevent the evaporation of the spi- 
rituous parts by the cracking or falling off of the luting, which 
would destroy the whole operation. When the basins have been 
exposed to the necessary heat they are taken off and left to cool 
after which they are separated, and the sublimated camphor is 
found adhering to the upper basin. By repeating this operation the 
camphor may be obtained purer at.d in larger pieces." 
The preparation of the crude camphor for the European market 
was for a considerable time monopolized by the Venetians, until the 
Dutch began to trade direct to the East Indies, where they learned 
the manner of purifying it ; these last kept the art a secret as long 
as they could, but it is now practised extensively in this country. 
It is sublimed in glass vessels, after being mixed with ^^th of its 
weight of quicklime ; it is then fused, either by increasing the heat 
suddenly when the sublimation is almost ended, without transferring 
the camphor to different vessels, or by melting the sublimed flowers 
in a vessel for that purpose : * When thus refined it is in large round 
cakes, about two or three inches thick, concave on one side, and 
convex on the other, and generally perforated. 
Chemical and Sensible Properties of Camphor. 
Camphor was for some time supposed to be a resin, and was so* 
designated by the Dublin College, but chemists are now agreed that 
it is a proximate vegetable principle, sui generis, and the researches 
of vegetable chemists have ascertained that it is a principle found in 
many trees and shrubs besides those from which the camphor of 
commerce is obtained, as from the roots of the cinnamon, cassia, and 
sassafras laurels ; from many of the vert icillata;, as sage, lavender, 
rosemary, hyssop, &c. ; from the roots of galangale, zedoary, ginger,' 
&c. ; and Zea describes a variety of camphor, procured from a tree 
in South America, termed Caratte by the natives, the botanical 
characters of which are not known, and from the bark of which the 
camphor exudes in the form of tears. An artificial camphor may 
be prepared by passing muriatic acid gas through oil of turpentine. 
Pure camphor has a strong, peculiar, fragrant, penetrating odour, 
and a bitter, pungent, aromatic taste, accompanied with a sense of 
coolness; it is white, pellucid, unctuous to the touch, and friable ; 
breaking with a shining, foliated fracture, which displays a crystal- 
line texture : notwithstanding its friability it is extremely difficult to 
See Aikin's Dictionary of Chemistry, and Thomson's Mat. Med. 
