310 On Spring and River Water, as 



constitution, as we shall by-and-by remark, supplies a result 

 which contradicts those conclusions which would be naturally 

 drawn from its physical condition. In winter, the water of 

 the Rhone, when at its minimum as to quantity, contains, all 

 limpid and blue as it is, more of the salts and gases in solution 

 than in the greatest heats of summer, at a time when it is 

 grey and muddy to the eye, but really at its maximum in che- 

 mical purity. 



The temperature of the Rhone water rises in summer to 

 77° Fahr., and more. It has then an insipid and disagreeable 

 taste, which does not leave it till it falls to 64°, or even to Gl°. 

 In winter, the temperature is sometimes as low as 34°, and in 

 the year 1837, when the temperature at Lyons ranged from 

 17° to 23° Fahr., the Rhone water descended to 33°, so that it 

 was within 1° of the freezing point. 



Comparing its composition in winter and summer, the fol- 

 lowing results were obtained. 



In July 1835, tliere was in somewhat more than 

 3 gallons (15 litres), 



In February 1338, 

 Centilitres. 

 27.3 

 13.G 

 10. 



Gram,:< ,-. 

 2.260 

 0.293 

 0.101 

 0.101 

 0.103 

 0.103 

 a trace, 

 do. 



In this table it will be observed that the water of the Rhone, 

 in approximating in winter to the good qualities of spring- 

 water in its physical properties, also approximates to its che- 

 mical combination by a considerable augmentation of its gases 

 and soluble salts. 



After these minute researches concerning the spring and 

 river water which supply the wells and fountains of the town 

 of Lyons, M. Dupasquier proposes to resolve the question, 



