243 On the Component Parts of Inn-Jlonei. 



The refidue, weighing as ahove - - 1 090 grs. 



was returned to the furnace, and expofed in 

 the bottom of a deep crucible, till fuch time as 

 a flight indication of fufion was obferved : 



o 



when cooled, the pieces weighed - - 1235 



Gained in weight by the fixation of oxygen 

 equal to 13*3 percent. - 145 g rs - 



In its prefent ftate this iron-ftone, in point of colour, 

 refembled the former. 



Tl> fracture, however, was i'moother, and more vitrified, 

 equally deftitute of tenacity to the tongue, and obedience, 

 to the magnet. 



3. An iron-ftone, which contained a large proportion of 

 fand, was expofed under fimilar circumftances to the fame 

 degree of heat — Quantity ufed weighed alfo - 175° S rs - 



When properly torrefied, weighed - - 1248 



Loft in fimple diftillation equal to 28-6 per 



cent. - 5° 2 g rs - 



The appearance which this ftone had affumed was of a 

 reddifii, irnall, granulated fracture, confiderably magnetic, 

 but fcarcely pofieffing any degree of adhefion to the tongue. 

 The refidue, weighing as above - - 1248 grs. 



was expofed to an equal degree of heat with 

 the former claries, by which the ftone fuf- 

 fcred throughout a flight degree of fufion — 

 when cool, the connected mafs weighed - 143 1 



Gained in weight by the combination of oxy- 

 gen equal to 14*6 - - - 183 



The colour of the ftone was now changed to a black, vi- 

 trefeent, nightly porous mafs, hard and refractory. I have 

 not given the fpecific gravities of the two laft natures of 

 ftones : iron-ftoncs containing equal portions of iron, in 

 fimilar itates of preparation, vary little in their fpecific gra- 

 vities. 



It 



