88 
Iron „ 
In the subsequent part of the opera^ 
tion I found that, when the iron -stone 
had assumed malleability, and brighten- 
ed under the file, a further quantity of 
oxygen was taken up, equal to - - 4*2 — 13*2 
C lay, lime and silex united in the stone - 13*7 
100 parts* 
The earths I found to be proportioned nearly as fol- 
lows : Clay 7 parts, calcareous earth 4, silex 2*7 = 13*7* 
II. Of a calcareous iron-stone, reduced in the same 
manner, I operated upon - - - 1750 grs» 
After being exposed to a similar distillation, 
I found it to weigh - - - - 1090 
Lost in water, acid, and sulphur, equal to 
37*7 per cent - - 660 grs* 
This iron-stone, when torrefied, exhibited a thin schis- 
ms of calcareous plates : its fracture also presented calca- 
reous lines running in various directions : its colour was 
reddish brown, partially fibrated, magnetic, and tena- 
cious to the tongue. 
I took of the same, mixed with charcoal dust, 1750 grs. 
and exposed the vessel to a temperature equal- 
ly high with the former. 
The residue, when carefully separated from 
the charcoal, washed and dried, weighed 922 
828 grs, 
Lost in simple distillation, as formerly shewn, 660 
Oxygen taken up by the charcoal, equal to 
9*6 parts in 100 - - 168 grs* 
In this state the stone was pulverulent, much frittered, 
and of a darkish grey colour. Its fracture exhibited a i 
number of white spots like madrepore. In many places 
