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§2 REPORT—1848, 
From close observation, I think at about 3 feet below the surface of the 
materials, which is the point where I draw off my supply from the furnace, 
very little combustion has taken place, and that the gases remain pretty much 
as they were in the bowels of the furnace. We observe, that as the gases 
rising from the furnace come in contact with the atmosphere, the whole burst 
out into a spontaneous flame, and it is my object to take them off at a point, 
where from the cover of the materials they are protected-from this combus- 
tion, and this from practice I find to be about 3 feet down. The large 
quantity of hydrogen in the analysis is puzzling, as anthracite coal only con- 
tains 2 or 3 per cent., and certainly the flame from au anthracite furnace, 
seen at night, is very different in colour from that escaping from furnaces 
using bituminous coal, the flame being of a bluish-white colour, and not at all 
yellow. The absence of carbonic acid in the first analysis, and its presence 
in the second, proves that the solid carbon of the fuel, after having been con- 
verted at the tuyéres into carbonic acid gas, by combustion with the oxygen 
of the blast, passing upwards into the middle region of the furnace, where 
carbon is in excess, absorbs an additional dose of it, and is thereby converted 
into carbonic oxide, a combustible gas ; and the whole gaseous eseape of the 
furnace, before the access of the atmosphere, appears to consist of about 50 
per cent. of highly inflammable gases and 50 per cent. of nitrogen, incombus- 
tible, but heated to a very high temperature. What use shall then be made 
of this great escape of combustible gas, after using it, as I do, as a mere heating 
medium? The passage through the boilers and stoves, where this heating 
effect is given, and where all access of atmospheric air is carefully prevented, 
would in no way interfere, under proper arrangements, with its subsequent 
use as a highly combustible gas in a suitable furnace. 
In reverberatory furnaces everything depends upon a good draught being 
maintained, so that, although the chimneys may be full of combustible gases, 
as we plainly see they are at night when passing the copper works, yet 
nothing can be done tu arrest them, they must pass off freely, so that a full 
supply of air may be drawn through the fire-grate ; this difficulty will always 
be a great obstacle to the curing of coal smoke, or to the condensation of me- 
tallic vapours passing off therewith over the bridge. But this does not at all 
apply to the blast-furnace; nothing there depends on draught, but every- 
thing on the power of the steam-engine to foree a column of air through 
40 feet of dense materials. The combustible gases passing over a rever- 
beratory furnace speedily combine in the stack with a fresh dose of oxygen, 
and become useless, whilst on the contrary, the carbonic acid resulting from 
combustion at the tuyéres in a blast-furnace, meeting with an excess of carbon, 
becomes again a combustible gas, as carbonic oxide. 
It therefore appears that the whole of the present arrangements of an iron 
works ought to be reversed, that the steam-engines and boilers for the blast, 
and for the forge and mill, should be on a platform above the back wall, the 
stoves being alongside the furnaces ; the steam should be raised in the boilers, 
and the air heated in the stoves, by the mere passage of the gases from the 
gas generator (the furnace) towards the gas furnaces, in which the refinery, 
boiling, puddling and balling processes necessary to convert pig into malle- 
able iron, should be performed. If the whole of the solid carbon put into the 
furnace be present at the tunnel head as carbonic oxide, requiring another 
dose of oxygen for saturation, and giving thereby a further production of 
heat, its entire combustion would without doubt, in gas furnaces, be amply 
sufficient for the mill and forge purposes. There is, besides, the hydrogen of 
the fuel, which from its volatile nature never reaches the tuyéres, and per- 
forms no useful part in a blast-furnace, but which would then be fully em- 
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