330 MINERAL RESIN. 



like coal, are composed principally of carbon in combination with 

 hydrogen. 



Sp. 1. Yellow Mineral Resin, or Amber. Pl. XLIV. 

 fig. 4.— Succin, Hauy. Bernstein, Werner. Gelbes Erd-Harz, 

 MoJis. — It occurs in small irregular massive pieces, which are 

 translucent or transparent, of a whitish, wine-yellow, or yellowish- 

 brown colour, and often incloses insects; the fracture is more or 

 less conchoidal, and the lusture resinous. It is brittle, and yields 

 easily to the knife. Its specific gravity is about 1*08. When 

 rubbed it gives out an agreeable smell, and becomes strongly 

 resino- electric. It softens when moderately heated, and at a higher 

 temperature it burns with a yellow flame, and fragrant odour. Its 

 constituent parts are resin, an empyreumatic oil, and succinic acid. 

 Amber is found in alluvial soil near Koningsberg, in Russia, where 

 it occurs in beds of bituminous wood; and is said to have been 

 observed imbedded in secondary limestone. It is also thrown up 

 by the sea on the shores of the Baltic, Germany, Poland, and 

 other countrys. 



Amber, when taken into the stomach, even in large quantities, 

 is perfectly inert ; it is introduced into the list of the materia 

 Medica only as affording, by distillation, an acid and oil, both of 

 which have been used in medicine. The oil is at first thick and 

 brown, but by repeated distillations with water, becomes thinner 

 and of a paler colour. It was formerly celebrated as an anti- 

 spasmsodic, and as such often prescribed in hysterical and convulsive 

 affections, in a dose of from ten to fifteen drops. It is now scarcely 

 ever employed, except as an external stimulating application in 

 hooping-cough, paralysis, and chronic rheumatism. The salt 

 {salsucciiii, E. D.), obtained along with this oil is impure succinic 

 acid, and is never used in the present practice. 



Sp. 2. Black Mineral Resin. — Schwarzes Erd-Harz, 

 Mohs.— This species is divided into three sub-species, viz. Naptha,' 

 Mineral Oil or Petroleum, and Mineral Pitch or Bitumen. The 

 two former only are used in medicine. 



1. Naptha.— Bitumen liquide blanchatre, Hauy.— This sub- 

 stance resembles oil, being perfectly liquid and transparent, feels 

 unctuous, and has a pale yellowish colour, inclining to brown. It 



