Report on the Bacteriology of Water. 



301 



sure a distinct advantage to the anthrax in its struggle with the 

 competing water forms. 



The results are again expressed in calculated averages, in the 

 following table. As before, the aeration was conducted for six days 

 at 15 — 16° C, a temperature at which the spores can germinate. 



State 

 of water. 



Number 

 of 



drops in 

 culture. 



Total bacteria 

 per 1 c.c. 

 original. 



Estimated 

 proportion of 



anthrax to 

 other bacteria. 



Remarks. 





1 



Many thousands 



1 : 10 





Non-aerated . . 



1 



Countless „ 



1 : 10 



As far as could 











judge the pro- 











portions were 











similar. 





3 





1 : 20 





Non-aerated . . 



3 







Impossible to 











estimate. 



Here it must be admitted that we failed in our attempt to as- 

 certain any effects of the aeration on the anthrax as compared 

 with the water organisms. 



We, meanwhile, altered the course of the inquiry as follows : — Each 

 flask, aerated and non-aerated, was placed, at the end of the six days, 

 as soon as the samples had been removed for plate cultures, at 60° C. 

 for twenty-four hours, and plates then made to ascertain, if possible, 

 what had happened to the anthrax — i.e., to see if spores had been 

 formed, and to what extent in the two cases. 



The following table summarises the results : — 



State of water, 



Number 

 of drops 

 used. 



Calculated number 



of anthrax 

 per 1 c.c. original. 



Remarks. 





1 

 1 



6 

 6 



120,000 

 99,000 

 100,000 

 125,000 













So far as the quantitative results go, we regard the experiments 

 here summarised as failures, because no stress whatever may be laid 

 on the actual numbers until we have made a larger series on these 

 comparative lines. 



We do think, however, that the results are valuable in another 



