the Anahjsc^ of M. Klaproth. 77 



perfectly pure, and that it contains only one-half per cent, 

 of muriate of soda. He found a little more in that of a 

 \ariety the crystallisation of which was less regular. 



The yellow variety has crystals of the same form : they 

 liave a beautiful topaz colour which arises from the com- 

 bination of one-eighth per cent, at most of iron. 



jNI. Klaproth was the more surprised at not finding sul- 

 phate of ammonia, as the muriate of that base was formed 

 m an atmosphere impregnated with sulphureous vapours. 

 Anahjs'is of the Sal Ammoniac of Bacharia^ 



Bucharian Tartary furnishes an ammoniacal salt which 

 differs in its external characters from that of the lava of 

 Vesuvius. We have not yet obtained sufficient ideas re- 

 specting its formation and natural history. 



M. JSIodel is the first person who made mention of it : 

 he assures us that several quintals of it are annually trans- 

 ported to Russia and Siberia, which gives reason to presume 

 that it is very abundant in Bucharia. The opinion he 

 forms, in regard to the rocks, is the more probable, as the 

 fraiiments of rock, which seem to be composed of argilla- 

 ceous schist or compact argil, are very often covered with 

 sal ammoniac. It is to be remarked, that among the grains 

 of this salt there are found also small insulated fragments 

 of yellow sulphur. M. Karsten has described it under the 

 name of conchoid sal ammoniac. 



It is grayish white, has a rough surface, is not very bril- 

 liant on the outside, and has a vitreous splendour on its 

 fracture, which is perfectly conchoid. Its fragments arc 

 irregularly angular ; it varies from semi-transparency to 

 opacity ; it is pliant, tender, light, of a pungent taste of 

 urine, and contains 



Muriate of ammonia - - 97" 50 



Sulphate of ammonia - - 2"50 



100 



AnahjsU of Sassolln. 



Natural sedative salt, known under the name of sassolin, 

 is a white salt interspersed with some spots of an isabella 

 colour, grouped in stalactites, soft and saponaceous to the 

 touch, easily pulverised, and composed, in a great measure, 

 of free boracic acid. 



M. Iloefer fir^tmade known at Florence the boracic acid, 

 which he found in the waters of the lake Cherchiaso and 

 in those of the lake of Castcl-Nuovo. 



Pro- 



