EXPOSED WATER AND FRESHLY FALLEN RAIN 



175 



May 7, 2 : 30 P. M. 



B 



Both sets of cultures, A and B, give the same kind of resuh, viz. , 

 a slower growth in the fresh rain-water than in that one month old. 



The results are plotted in figures 43 and 44, and are in substantial 

 harmony with those obtained in the two preceding experiments. Care 

 was taken in this experiment to have the temperature of the stale and of 

 the freshly fallen rain-water alike by placing the carefully covered 

 dish containing the former out of doors by the side of the latter while 

 the fresh water was being collected. The fresh and the stale water 

 were then kept side by side throughout the entire experiment. 



