180 



Dr.. A. Macfadjen. On the Inflo.tiicc of 



employed. The slight divergence on the left-hand side of the curve 

 from that of P is probably due to his colouring matter in the yellow 

 spot. Attention must be again called to the fact that these curves are 

 practically identical with those obtained by the normal eye when it 

 measures a spectrum of very feeble liuninosity, and also agree ^nth 



the results obtained by measuring the diminution of each ray when it 

 first becomes invisible, and making a curve of the reciprocals of the 

 numbers, taking the highest point of it as 100. This is clearly shown 

 in Part III, " Colour Photometry."* It may be mentioned the scale 

 of the prismatic spectrum employed is the same . in this commimica- 

 tion as in that paper, the wave-lengths of each scale nmnber being 

 given in it. 



On the Influence of the Teniperatiu^e of Liquid Air on Bacteria." 

 By Allan Macfadyen, M.D. Communicated by Lord Lister, 

 Pres. E.S. Eeceived December 15, 1899,— Piead February 1, 

 1900. 



The experiments of Dr. Horace T. Brown and Mr. Escombet have 

 shown that no appreciable influence is exerted upon the germinative 

 power of seeds, when exposed for 110 hours to the temperature of 



* • Pliil. Trans.,' A, vol. 183, 1892. 



t Roy. Soc. Proc / vol. 62, 1898, p. 160. 



