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their el ementary proportional number shews,)and the least coherent, would be separatedin the largest quantities.

6thty. The heat of flames may be ac-tually diminished by increasing their light,(at least the heat communicable to othermatter,) and vice versa. The flame fromcombustion which produces the most intenseheat amongst those I have examined, isthat of a mixture of oxygene and hydro-gene in slight excess, compressed in a blow-pipe apparatus, and inflamed from a tubehaving a very small aperture.* This flameis hardly visible in bright day-light, yet itinstantly fuses very refractory bodies; andthe light from solid matters ignited in it, isso vivid as to be painful to the eye.

July, 1816.

“ * John George Children, Esq. first proposed to roethis application of the biow-pipe by compression, im-mediately after I had discovered that the explosion fromoxygene and hydrogene might be arrested by very smallapertures,i and I first tried the experiment with a fineglass capillary tube. The flame was not visible atthe end ol this tube, being overpowered by the brilliantstar of the glass ignited at the aperture.” The resultsproduced by the action of this flame on solid bodies,were so similar to those published by Mr. Hare someyears ago, that I did not think them worthy of par-ticular notice.