connected with Health and the Arts. 317 



17th to the 25th of June, the mean temperature of the water 

 of the Rhone had been, in the stream, 74° Fahr. ; in the well 

 of the Botanic Garden,"a covered reservoir, where it continues 

 for a time, it was as high as 77° ; and in the fountains which 

 this reservoir feeds, it was found, according to the distances, 

 at 72°, 70°, and 68°, the distance in the last case being about 

 1600 yards. Hence, it can scarcely be expected that, by any 

 subterranean transit through pipes or otherwise, the tempera- 

 ture of water will be materially improved. 



From the marked superiority which the spring-water on 

 the margin of the Saone possesses over the water of the Rhone, 

 in the important points both of clearness and temperature, and 

 the trifling importance he assigns to the presence in these 

 springs of a small cpiantity of the carbonate of lime, which, in 

 fact, is advantageous, M. Dupasquier gives it as his mature 

 and decided opinion that the former should be employed for 

 the supply of Lyons. This leads to a discussion on the pro- 

 bability of the obstruction of the conduits by ferruginous 

 depositions or calcareous incrustations, and he concludes that 

 all this might be prevented by constructing great earthen 

 tanks, through which the water would needs pass before it 

 entered the pipes ; or that, by effectually excluding the atmo- 

 spheric air, the water might maintain its primitive composition 

 and have little or no tendency to deposit foreign matter. 



Desirous of elucidating, as far as possible, the comparative 

 value of spring and river water, in so far as the question in- 

 volves the public health, M. Dupasquier thought of more par- 

 ticularly examining the organic matter which they contained. 

 In all the specimens submitted to examination, chemical in- 

 vestigation exhibited traces of an animo-vegetable substance, 

 but without yielding any more satisfactory result. This sug- 

 gested the propriety of having recourse to the microscope ; 

 and for the avoiding of the many illusions inseparable from 

 such investigations, the author obtained the assistance of Dr 

 Donne, already favourably known for his microscopic labours. 

 The following are the principal results he obtained. 



let, In winter 1839, at a temperature below the freezing 

 point, the Rhone being at its minimum of volume and in its 

 state of greatest clearness, water taken from the current ex- 



VOt. XXX. NO. LX. AI'IUL 1841. X 



