methods of lighting the mines without producing its explosion . 1 3 
derably the size of the flame, and rendered it more liable to 
go out by motion ; and the following experiments appear to 
show, that if the diameter of the upper orifice of the chimney 
be not very large, it is scarcely possible that any explosion 
produced by the flame can reach it. 
I threw into the safe lantern with the common chimney, a 
mixture of 15 parts of air and 1 of fire-damp : the flame was 
immediately greatly enlarged, and the flame of the wick 
seemed to be lost in the larger flame of the fire-damp. I 
placed a lighted taper above the orifice of the chimney-: it 
was immediately extinguished, but without the slightest pre- 
vious increase of its flame, and even the wick instantly lost 
its fire by being plunged into the chimney. 
I introduced a lighted taper into a close vessel containing 
15 parts of air and 1 of gas from the distillation of coal, suf- 
fered it to burn out in the vessel, and then analyzed the gas. 
After the carbonic acid was separated, it appeared by the test 
of nitrous gas to contain nearly j of of its original quantity 
of oxygene ; but detonation with a mixture of equal parts of 
hydrogene and oxygene proved that it contained no sensible 
quantity of carburetted hydrogene gas. 
It is evident, then, that when in the safe lantern j the air 
gradually becomes contaminated with fire-damp, this fire- 
damp will be consumed in the body of the lantern ; and that 
the air passing through the chimney, cannot contain any in- 
flammable mixture. 
I made a direct experiment on this point. I gradually threw 
an explosive mixture of fire-damp and air into the safe lantern 
from a bladder furnished with a tube which opened by a large 
aperture above the flame ; the flame became enlarged, and 
