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flaming a stream of coal gas, and passing-a piece of wire gauze gradually from the■summit of the flame to the orifice of thepipe, the result was still more instructive;for it was found that the apex of the flameintercepted by the wire gauze afforded nosolid charcoal; but in passing it downwards,solid charooal was given off in considerablequantities, and prevented from burning bythe cooling agency of the wire gauze ; andat the bottom of the flame, where the gasburnt blue in its immediate contact withthe atmosphere, charcoal ceased to be de-posited in visible quantities.

This principle of the increase of the bril-liancy and density of flame by the produc-tion and ignition of solid matter, appearsto admit of many applications.

1st. It explains readily the appearancesof the different parts of the flames ofburning bodies, and of flame urged by theblow-pipe: the point of the inner blue flame,where the heat is greatest, is the pointwhere the whole of the charcoal is burnt inits gaseous combinations without previousdeposition.

2dly. It explains the intensity of the light' e 2