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V. Farther experiments on the combustion of explosive mixtures 
confined by wire-gauze , with some observations on flame. 
By Sir H. Davy, LL. D. F. R. S. V.P.R. I. 
Read January 25, 1816?. 
I have pursued my enquiries respecting the limits of the 
size of the apertures and of the wire in the metallic gauze, 
which I have applied to secure the coal miners from the explo- 
sions of fire-damp. Gauze made of brass wire, of an inch 
in thickness, and containing only ten apertures to the inch, or 
100 apertures in the square inch, employed in the usual way 
as a guard of flame, did not communicate explosion in a 
mixture of 1 part of coal gas and 12 parts of air, as long as 
it was cool, but as soon as the top became hot, an explosion 
took place. 
A quick lateral motion likewise enabled it to communicate 
explosion. 
Gauze made of the same wire, containing 14, apertures to 
the inch, or 196 to the square inch, did not communicate 
explosion till it became strongly red hot, when it was no 
longer safe in explosive mixtures of coal gas ; but no motion 
that could be given to it, by shaking it in a close jar, produced 
explosion. 
Iron ware gauze of and containing 24,0 apertures in the 
square inch, was safe in explosive mixtures of coal gas, till it 
became strongly red hot at the top. 
