BACTERIAL CONTENTS OF VARIOUS WATERS 91 



month the average of the observations made by him 

 during three years, 1887-90, of the water derived from 

 the Seine at Ivry, the Marne at St.-Maur, and the 

 Ourcq. 



Bacterial Contents of the Seine, the Marne, and the Ourcq (Miquel) 

 Number of Micro-organisms in 1 c.c. of Water 



From this table it will be seen that the same phe- 

 nomenon is observable as in the case of the Thames and 

 the Lea, viz., that it is during the winter months that 

 the largest, and during the summer that the smallest, 

 number of bacteria are present in the water. 



In another series of experiments Miquel has col- 

 lected Seine water above and below Paris, and also at 

 St. -Denis after it has received the drainage from Paris. 

 He found that at Choisy, above the city, there were 

 300 in 1 c.c., at Bercy, in the immediate vicinity of 

 Paris, 1,200, whilst at St.-Denis the numbers rose to 

 200,000 per c.c. 



An examination of the water supplied to Lyons 

 from the rivers Ehone and Saone has been made by G. 

 Eoux. 1 The river Khoiie water is filtered through sand 



Precis d j Analyse microbiologique des Eaucc, p. 258. Paris, 1892. 



