£roW* 
89 
lime was distinctly perceived : when pulverised* it spark- 
led in the flame* dissolved rapidly in acids with a vio- 
lent effervescence* was less magnetic than the former^ 
though possessing a great tendency to adhere in the form 
of fibres* From this treatment the practical analysis of 
this stone will stand as follows : 
In the assay furnace it yielded* of super -carbonated 
crude iron, per cent* - = 37-5 parts 
Water, acid, and sulphur lost, as for- 
merly shewn, - 37*7 
Oxygen taken up in the first stage of 
de- oxygenation - - - 9 ° 6 
Afterwards taken up in cementing the 
iron-stone to render it malleable - 4 8 9“14 8: 5 
Clay, lime and silex - •«* - 10 s 3 
100 parts 
By dissolution in acids, I found the earthy parts to be 
nearly as follows : Lime 5*2-— Clay 3 8 i— Silex 2~10 s 3„ 
This analysis must not, however, be taken as' a stand- 
ard whereby the quantity of iron and earth is to be judged 
of in calcareous iron-stones in general* The iron-stones 
of this class, contain much less iron than argillaceous or 
even siliceous iron-stones ; 28 to 32 per cent are products 
more commonly met with than 37 and upwards ; the dif- 
ference in point of metal being made up in lime and clay* 
In stating the quantity of oxygen disengaged, I conceived 
it proper to adduce iron-stones, though of different classes^ 
yet containing nearly the same weight of metal as the 
quantity either disengaged or absorbed must be in a direct 
ratio to the existing quantity of iron* 
His I operated with a siliceous iron-stone, weighing 
also - 1750 grs, 
composed of small pieces, and exposed for 
the same length of time, and to the same 
M 
