Report on the Bacteriology of Water. 283 



On October 26, 1892, we examined the contents of a flask which 

 had stood since March 5, 1892, in a north window of the laboratory, 

 i.e.. it had remained nearly eight months nndistnrbed, at ordinary 

 temperatures and in diffused daylight. 



This flask was an interesting one in many respects. When first 

 placed in position, on March 5, it had received a charge of about 

 300 c.c. of fresh Thames water, infected with a very strong charge of 

 virulent anthrax taken from a potato culture, but we discarded it at 

 the time because (1) the culture was found to contain so many 

 spores, and (2) so much of the starch of the potato had been trans- 

 mitted with the charge that we judged it better to renew the experi- 

 ments we were engaged in. 



Daring the summer the water in this flask became quite green 

 with microscopic algae, evidently developed from the Thames water, 

 and it seemed worth while on October 26 to test the water for 

 anthrax, to see if the presence and activity of the algae had eliminated 

 that organism. 



The positive results of the analysis are shown below in Table G. 

 On several of the plates no anthrax could be found at all ; but in the 

 two cases recorded ia the table there was no doubt whatever. 



