Report on the Bacteriology of Water. 



213 



effected their destruction. Roux ('Ann. de l'lnst. Past.,' 1887, p. 445) 

 again insolated the spores when dispersed in the aqueous humour of 

 the ox-eye, and found them destroyed in from twenty-nine to fifty- 

 four hours, whilst Pansini (' Rivista d'Igiene,' 1889) observed their 

 destruction on potatoes in from four to five hours, in gelatine in from 

 six to seven hours, and in broth in from thirty minutes to two hours. 

 In all these experiments it will be seen that nutrient culture media 

 were employed for the insolation, and that the spores were destroyed 

 in a much briefer period of time than in my experiments, in which 

 they were insolated in Thames water. This same phenomenon of 

 the spores of anthrax being more resistant to the action of sunshine in 

 ivater than in ordinary culture materials has also been observed by 

 Straus (' Societe de Biologie,' 1886, p. 473) and by Momont (' Ann. 

 de l'lnst. Past. ,'1892, p. 21), who both, however, appear to have made 

 use of distilled water only. 



II. Vitality and Virulence of Anthrax Spores in Thames Water 

 (Second Series of Experiments). 



Owing to the very small number of anthrax germs introduced into 

 the water in the First Series of experiments, it was deemed advisable 

 to carry out a Second Series in which a much larger number were 

 inoculated into the several waters, whilst as a further modification 

 and check, the infection was made with virulent anthrax from a 

 totally different source to that employed in the First Series. 



The infection was made as follows : — 



50 c.c. of Thames water previously steam sterilised were placed in 

 a small sterile stoppered bottle, and inoculated with 5 needle loops 

 from an anthrax culture in glycerine agar of 3 weeks' age, and with 

 4 needle loops of another similar culture of 3-| weeks' age. The 

 water thus infected was then violently shaken, after which three 

 portions of 5 c.c. each were measured with a sterile pipette into 

 three flasks containing the three following waters respectively : — 



(a.) Unfiltered Thames water (750 c.c). 



(6.) Thames water sterilised by filtration through porous porcelain 

 (1000 c.c). 



(c.) Thames water sterilised by steam (1000 c.c). 



The waters thus infected were violently agitated to secure even 

 distribution of the anthrax, after which each water was divided 

 amongst a number of small flasks as follows : — 



VOL. LIU. 



Q 



