De Buffon- 



72 THE LAND-MARKS OF 



next deals with the hypothesis that the poison 

 causes death by universal inflammation. He 

 contended that post inortem appearances did 

 not indicate anything of the kind. With refer- 

 ence to Mead's theory, he denies that any salts 

 are to be found in snake-poison, and holds that 

 what Mead saw under the microscope must 

 have been a " kind of skin from the mouth of 

 the snake" (epithelium) " which he himself 

 ^Tafgem* occasionally observed." The celebrated De 

 ^°'^^' Buffon, on the other hand, maintained that the 



by lenses, and furnished a greenish light of great 

 intensity, but yet produced no perceptible heating 

 action when it was allowed to fall upon the face of a 

 sensitive thermoscope. A similar separation of light 

 and heat seems to be effected in nature, in the light 

 reflected by the moon. Melloni concentrated the rays 

 of the moon by means of an excellent lens of a metre 

 in diameter, and obtained a brilliant focus of light of 

 one centimetre in diameter, the intensity of which 

 consequently was nearly ten thousand times greater 

 than that of the diffused light of the moon ; upon direct- 

 ing this focus of light upon the face of a very sensitive 

 thermomultiplier, only an extremely feeble indication 

 of heat was obtained." Miller adds in a foot-note, 

 " Notwithstanding these results, Melloni maintained 

 during the latter days of his life the identity of the 

 agent which produces light and heat." 



