4(58 Report on the Bacteriology of Water. 



or to osmotic phenomena, or to minute changes of temperature 

 incident to the precipitation, cannot be determined. I have discussed 

 the collateral effects of these condensations, as difficulties in the obser- 

 vations, in their place, bat special experiments are needed in regard 

 to the other points. 



(6.) In a few cases there is positive evidence that volatile antiseptic- 

 substances e.g., from scorched cotton wool inhibit the growth. 

 Here, again, special investigations are needed to determine the effects 

 of these on the curves, a line of experimental inquiry for which the 

 method is admirably suited. 



