462 



EEPORT — 1893. 



Action of Sunsliine on Anthrax Spores suspended in Water. 

 (Percy Frankland.) 



The figures refer to the number of anthrax spores contained in a cubic 

 centimetre of water. 



These results clearly show that the bactericidal action of light is very 

 considerably greater in water containing common salt (1, 3, or 10 per 

 cent.) than in distilled water ; whilst, on the other hand, the addition of 

 sodium sulphate in the same proportions has little or no influence in this 

 respect. It is worthy of note also that an addition of 10 per cent, sodium 

 chloride appears to exercise even a considerable bactericidal effect in the 

 dark. 



The specific effect of the sodium chloride in enhancing the bactericidal 

 action of light is even still more conspicuously brought out by the series 

 of experiments — also on anthrax spores — recorded in the following 

 table :— 



Action of Sunshine on Anthrax Spores suspended in Water. 



(Pbect Frankland,) 



Spores produced at 18-20° C. 



The figures refer to the number of anthrax spores found in a cubic 

 centimetre of water. 



In addition to those departments of bacteriology which I have briefly 

 touched upon in this survey, there are many others, also of great interest 

 to chemists, which might have been appropriately introduced had time 

 permitted. Thus the more important subjects which I have had to pass 

 over are — 



1. The discoveries in the bacteriology of agriculture, including such 

 important chemical changes as nitrification and the fixation of free 

 nitrogen by leguminous plants (which must be regarded as some of the 

 most important contributions to vegetable physiology ever made) have 

 shown that really the most important fermentation industry, and which 

 is far more extensive than all other industries put together, is agriculture. 



