88 MICRO-ORGANISMS IN WATER 



obtained from polluted sources a safe article for con- 

 sumption. See also p. 252 in chapter on ' The Multi- 

 plication of Micro-organisms/ for experiments on the 

 vitality of the typhoid bacillus and other organisms in 

 artificially frozen water. 



Hail. The bacterial contents of hailstones have 

 been examined by Bujwid, 1 and later by Foutin. 2 In 

 both cases the hailstone was first carefully washed to 

 rid it of chance external contamination and then melted 

 and plates poured. Bujwid found in Warschau as 

 many as 21,000 organisms per c.c., whilst Foutin found 

 in St. Petersburg in 1 c.c. of hailstone water only 729. 

 Bujwid mentions that the stone he examined was an 

 unusually large one, being 6 cm. long and 3 cm. 

 thick. 



Rain. Curiously but few determinations of the 

 number of organisms in rain have been made. Mique! 

 records having found 4'3 in rain water collected at 

 Montsouris, therefore outside Paris, and 19 in a cubic 

 centimetre in the middle of the city. Both experiments 

 were made during a rainy season. The average number 

 found in the rain water at Montsouris observatory 

 for the three years 1883-86 was 4'3 bacteria and 

 4*0 moulds per c.c., which, with a rainfall of 60 c.c.,. 

 signified, says Miquel, that about 5,000.000 micro- 

 organisms fall annually per square metre surface in that 

 locality. 



If freshly fallen snow, snow from the regions of 

 glaciers and ice, contain micro-organisms, it will be 

 readily understood that waters which are exposed to 

 contamination will contain very large numbers of 

 bacteria. 



1 ' Die Bakterien in Hagel-Kornern,' Centralblatt fur Ba~kteriologie, 

 vol. iii. 1888, p. 1. 



2 ' Bakteriologische Untersuclmngen von Hagel,' ibid. vol. vii. 

 1890, p. 372. 



