CAMPHOR. 451 



it to a second sublimation in large glass vessels. The 

 Dutch were the only people for along time by whom 

 camphor was exclusively refined. It is now refined 

 in England and other parts of Europe. 



Camphor is well known as a white friable substance, 

 having a peculiar aromatic odour and a strong taste. 

 Some chemists consider it as a concrete vegetable oil. 

 It melts at a temperature of 288, and boils at 400 

 Fahrenheit. Its specific gravity is less than that of 

 water. It is very inflammable, burning with a white 

 flame and smoke, and leaving no residue. Alcohol, 

 ether, and oils dissolve it. The only indication 

 whereby it appears that water acts upon camphor 

 is that of acquiring its smell ; it is said, however, 

 that a Spanish surgeon has effected the solution in 

 water by means of carbonic acid*. Camphor may 

 be burned as it floats on the surface of water. The 

 best kind is not altered or sensibly diminished by 

 mere exposure to atmospheric air, but that coming 

 from Japan, obtained by boiling the wood, is so 

 extremely volatile that if, in warm weather, it is placed 

 in an open vessel, it evaporates completely. Camphor 

 of the best quality, obtained naturally in Japan, is 

 not nearly so volatile. It has been found that a 

 hundred pounds of this description of the drug loses 

 only ten pounds by evaporating freely in the air, 

 while in the same period of time the same quantity 

 artificially obtained entirely evaporates away f. 



Camphor has been found to exist in numerous 

 plants, whence it , may be obtained by distillation. 

 Neumann and other chemists extracted it from the 

 roots of zedoary, thyme, sage, the inula hellenicum, 

 the anemone, the pasque flower, and other vegetables ; 

 and it is considered probable that it is contained, more 

 or less, in almost all the labiated plants. Experi- 

 ment has shown that the plants whence it is extracted, 



* lire's Dictionary of Chemistry. 

 f Journal des Connoissances, &c. 



