1825.] Mr. Dames on Flame. 451 



opinion on the subject, while it is, at the same time, in accord- 

 ance with the views of Mr. Sym. 



From the nature of flame, as explained in this paper, we are 

 enabled to assign a cause for many of the phenomena of com- 

 bustion, some of which could not be easily accounted for on 

 any other principle. 



The great power of the Argand burner is owing, as is well 

 known, to the stream of air which passes up the flame. This 

 stream of air nearly doubles the surface of the flame ; and, as 

 upon the principle just stated, the intensity of the flame in- 

 creases, cateris paribus, in the same ratio, the effect is only that 

 which might have been expected. 



It shows us why combustion is comparatively feeble in rarified 

 air : for in this case there is a deficiency in the supply of the 

 oxygen, and the combustion at the surface of the flame must 

 be accordingly diminished. We see, too, a reason for the Ti- 

 gorous combustion which is occasioned by introducing the 

 burning body into oxygen gas. 



Some of the researches of Sir H. Davy might, at first view, 

 appear to militate against the principle which is here applied ; 

 since he found that, in an atmosphere so much rarified as to 

 extinguish a small flame of hydrogen gas, a large flame of the 

 same material might still be supported. This objection, though 

 plausible, may, I think, be easily obviated. The languid action 

 of the small flame does not enable it to make use of the scanty 

 supply of oxygen ; but the increased energy of the larger 

 flame, presents, by its greater heat and surface, an augmented 

 attractive force for the oxygen, which it seizes with avidity as 

 long as any remains. 



When candles and lamps produce, while burning, a quantity 

 of smoke, the circumstance is owing to imperfect combustion 

 arising from a deficiency of oxygen. If the lamp or candle 

 in this state be put into a vessel containing oxygen gas, the 

 Smoke will, for obvious reasons, be no longer afforded. 



It is found that gas burners are, to a certain point, capable 

 of giving a greater quantity of light, in proportion to the number 

 of holes made for the emission of the gas, although beyond 

 that point the illuminating power is diminished. The fact may, 

 I conceive, be explained upon the principles which I have 

 attempted to establish. By increasing to a certain extent the 

 number of perforations, we augment the external surface of the 

 flame; and, therefore, according to the views of Mr. Sym, we 

 obtain a greater quantity of hght : but if we exceed that 

 number of perforations, the flames, which were before distinct, 

 become united, and form only one flame, the surface of which 

 must obviously be less than it was in the other case ; and the 

 quantity of light will accordingly be, by theory, what we 

 find it actually is in fact. It ought to be observed, however, 



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