Jale DifeoViries in Science. 2^7 



Napione has defcribed a calcareous ftone found in a vein 

 of the primitive mountains of the valley of Seflia. It is white, 

 has a pearly fplcndour, and produces nofenfible effervefcence 

 with acids. When calcined it makes good lime, when rub- 

 bed it becomes phofphorefcent. It gave when analyfed : 

 Lime - - - 5^' 79 

 Magncfia - - iO"4i 



Oxyd of iron - - oi'OO 

 Carbonic acid - - 43*00 

 Water ^ - - icj-oo 

 Poiret has made known a kind of foffil wood, which he 

 found near Laon. The infide of this wood was covered with 

 a ftonv fubftaiice exceedingly hard, filiceous, and depofited in 

 lamintE ; but the external ftrata, thofe which appear to have 

 belonged to the lic-er, and even to the aubier, appeared in long, 

 capillary, brittle filaments, which, when ftruck by the contact 

 of the air, aflumed the form of woolly flakes. They were 

 interwoven in the fame reticulated form as that which they 

 affcft in the living timber. In the laft place, the part which 

 conftituted the epidermis had become a very fine black-car- 

 bonaceous powder, which ftained the fingers, and had all the 

 characters of charcoal. 



Pontier has fent to the fchool of mines at Paris, a new 

 mineral fubftance found a la Bajlide de la Carrade, near 

 Caffin, in the department of the Var. It is of a dark brown 

 colour almoft like that of brown blend, and has metallic 

 fplendour : its fpecific gravity is 4-0326. It is difficult to 

 be fufed by the blowpipe. The glafs it produces is of a dirty 

 greenifli colour. Taflaert has analyfed this fubftance, and 

 found that it contains : 



Chromic acid - - ^3'^ 



Oxyd of iron - - 36*0 



Lofs - . - - 00-4 

 But a new analyfis of it by Vauquelin and Taflaert has 

 given : 



Chromic ^cid - - 43.0 



Oxyd of iron - - 34'7 



Alumine - - - 20*3 

 Siiex . - - - oa.o 

 Vol. VII. LI Lelievre 



