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processions, accompanied by the widows, orphans, and sur- 
vivors of the Oaks explosion, as they passed slowly through 
the streets which were lined with spectators, will not readily 
forget the solemn impression then made, the sight of the 
numerous train of widows brought tears into many eyes. 
On the latter day the shops lining the principal thorough- 
fares were closed, and business suspended. 
FIRE DAMP. 
Fire Damp, Marsh Gas, Pit Gas, or Light Carburetted 
Hydrogen, Symbol C H 2 ; sp. gr., '552*100 cubic inches 
weigh 17*12 grains. Specific gravity as compared with 
hydrogen 8 to 1. 
Fire Damp is a natural product which issues from the 
ground, and admits of being kindled. It is a product of 
decomposition from beds of coal, and when it mingles 
with air forms an explosive mixture. It is a colourless, 
invisible, inodorous gas, scarcely soluble in water ; it does 
not support combustion or respiration. "When breathed in a 
pure state it is fatal to animal life, but it is not very noxious 
when mixed with air, even when it forms 8 or 10 per cent, 
of the mixture the miners can work in it ; however, when it 
is very strong it has been known to render them insensible, 
but the usual effects are a tightness across the forehead, with 
headache, which happens some time before insensibility takes 
place. 
Fire Damp alone does not explode, it must be mixed with 
air or oxygen before this phenomena can show itself. If 
mixed with too much air, explosiveness is again lost. If the 
proportion be diminished to three or four times that of the 
fire damp, or increased to more than fourteen times its 
measure, explosion does not happen; for where the volume 
of air is very small an amount of oxygen sufficient to burn 
the fire damp is not furnished ; where the quantity of air is 
too large it prevents the spread of flame, by conducting 
away heat, and preventing the temperature rising high 
