Of the Light manifested in Combustion. 219 



common size furnishes, its light would have been that 

 of 25. 



On measuring the intensity of the light of this taper 

 by means of the photometer, it was found to be only 

 1.52, or a little more than one degree and a half, 

 instead of 25! 



Though I had been led, by the results of my former 

 experiments and the conclusions I had drawn from 

 them, to expect that the light of this little taper would 

 be very feeble, yet I confess that the result of the 

 experiment surprised me very much. I repeated the 

 experiment several times with the utmost care, and 

 though this taper sometimes gave a little more light 

 during a few moments, yet it more frequently gave 

 considerably less ; and I am persuaded that in estimat- 

 ing its mean intensity at one degree and a half, that is 

 quite as much as can be allowed. 



Here, then, is a flame, and even the flame of a wax 

 taper, which is 16 times more feeble than it ought to 

 have been, were light really a substance emitted by 

 inflammable bodies, and its quantity proportional to 

 the quantity of the inflammable matter consumed. 



This result can easily be explained, if we admit the 

 hypothesis which supposes light to be analogous to 

 sound. The flame of the taper was so small that the 

 particles of which it was composed, though extremely 

 hot, no doubt, at the moment of their formation, were 

 nevertheless so rapidly cooled by the frigoric influence 

 of the surrounding cold bodies that they had hardly 

 time to shine an instant, before they became too cold 

 to be any longer visible. 



The extreme feebleness of the light in this experi- 

 ment might easily have been mistaken for a proof that 



