PHYSETER MACROCEPHA.LUS. 37 



brittle, unctuous substance, usually in small scales, has scarcely 

 any taste, and but little smell. Its specific gravity is 9.433. It 

 melts at 1 12°, burns with a clear flame when exposed to a higher 

 temperature, and is volatalized by heat, being at the same time 

 partially decomposed. It dissolves readily in hot alcohol, ether, 

 and oil of turpentine, but separates as the fluid cools. It is com- 

 pletely soluble in the fixed oils. It is insoluble in water, but can 

 be diffused in that fluid by means of the yolk of egg or mucilage. 

 It combines with the alkalies, forming soaps, which are not quite 

 so perfect as those prepared with the common fat. The weaker 

 acids do not act on it, but the strong sulphuric acid dissolves it, 

 forming a dark coloured, thick, soapy solution. When a mineral 

 acid is added to the soap which it forms with potass, a peculiar 

 fatty substance is precipitated, which is called cctic acid by 

 M. Chevreul. It was formerly supposed to be the basis of the 

 common biliary calculi, but Chevreul shewed that it differs essen- 

 tially from this substance, which he has called chloresterine. 



The highly esteemed odoriferous substance, so well known by 

 the name of ambergris, has been discovered in the intestines of the 

 Spermaceti "Whale. It has been observed, that the Whales that 

 contain ambergris are always lean and sickly, yield but very little 

 oil, and seem almost torpid ; but it is uncertain whether it is the 

 cause or effect of disease. Ambergris occurs in irregular shaped 

 masses, of various sizes, which have a compact texture, and an ash- 

 grey colour, marked with yellowish, brown, and white streaks. Its 

 specific gravity varies from 0.849 to 0.844. It is generally brittle, 

 feels unctuous, and if good adheres like wax to the edge of a 

 knife with which it is scraped. It has an agreeable smell, which 

 improves by keeping. Its taste is insipid ; it melts when heated 

 at 144° ; and at 212° is volatalized in the form of white vapour. 

 According to the analysis of Bouillon la Grange, 100 parts of am- 

 bergris contain 52.7 adipocere, 30.8 resin, 11.1 benzoic acid, and 

 5.4 charcoal. From more recent experiments it appears to con- 

 sist principally of a peculiar matter, which is called amlrein, by 

 Pelletier and Caventou ; this substance bears a great resemblance 

 to chloresterine, and is obtained by digesting the ambergris in 

 alcohol, which deposits chrystals of ambrein as it cools. 



E 



