COLLECTION OF MINERALS. 285 



able number of specimens, most of which are 

 from the departments of Puy-de-D6me and Can- 

 tal. On one of the upper shelves is a beautiful 

 specimen of the primitive variety from Czarles, in 

 Transylvania. This species is remarkable for its 

 great specific gravity, and is the heavy spar of 

 former mineralogists. The radiated variety has 

 been long known under the name of Bologna 

 stone ; because the phosphorous, which bears 

 the name of that city, is obtained by calcining 

 this stone. 



The carbonate of barytes, found principally in 

 England, is in the thirteenth case. It is a poison 

 for all animals, and is named in that country 

 ratsbane. Regular forms of this substance are 

 very rare. On the stage for study is a beautiful 

 group of crystals, terminated by pyramids with 

 six sides. 



The sulfate and the carbonate ofstronlian, in 

 the fourteenth case, are only interesting to mine- 

 ralogists. In the bottom of the case is a beau- 

 tiful group of crystals of the former substance, of 

 a very great size ; it weighs twenty pounds, and 

 was presented by Dolomieu. Some superb spe- 

 cimens of limpid crystals and concrete masses are 

 distributed on the shelves. They were collected 

 in Sicily by M. Lucas, whose last excursion in that 

 country has enriched the Museum with a multi- 



