186 
Iron • 
marks, but I am not at present qualified to apply them to 
practical purposes* 
“ Iron is capable of combining with Potassium and Sodi- 
um : these alloys are more fusible and whiter than iron, 
and effervesce copiously in water. There is great reason 
to believe that alloys may be formed of iron and the metals 
of the earths. Cast iron , which is produced by fusing 
iron ores with pitcoal, during its conversion into malleable 
iron, affords but one fourth of its weight of a glass, which 
consists of silex. alumine, lime, oxide of iron, and oxide 
of manganesum. In the process for reducing cast iron 
into malleable iron, called blooming , the iron, after being 
fused in a forge by a fire of charcoal, is hammered, whilst 
in a soft state, on an anvil, by a large hammer worked by 
water ; a vivid combustion, which seems to be connected 
with the formation of the glass and the oxides, takes place j 
on the surface of the mass : that the earths are formed by 
the oxidation of metals combined in the cast iron seems 
probable from the circumstance of the combustion ; and 
the idea is confirmed by the distinct metallic character of 
cast iron ; it is white, crystallized, and has all the appear- 
ance of a perfect alloy. Specimens of cast iron usually 
9? 
contain likewise sulphur and carbon/ 
20thly. I close these remarks by the following quota* 
tion from Mushet— 5 Pin Mag. 366. 
On the relative Proportions of Coals and Iron - Stones used 
at the Blast-Furnace , and of their proper Application to 
Use . By Mr, David Mushet, of the Clyde Iron- 
Works . Communicated by the Author . 
IN the smelting operation a just proportion and asso- 
ciation of materials and mechanical construction ought to 
be blended in order to produce the best possible effects. 
Under the former, are comprehended the cokes, iron- 
stone, limestone, and blast ; by the latter is understood 
