440 DRAINAGE BY BORING. 
This practice has been extensively employed at Paris, not 
merely for carrying off ordinary surface-water, but for the dis- 
charge of offensive and deleterious fluids from chemical and 
manufacturing establishments. A well of this sort received, 
in the winter of 1832538, twenty thousand gallons per day 
of the foul water from a starch factory, and the same process 
was largely used in other factories. The apprehension of 
injury to common and artesian wells and springs led to an 
investigation on this subject by Girard and Parent Duchatelet, 
in the latter year. The report of these gentlemen, published 
in the Annales des Ponts et Chaussées for 1833, second half- 
year, is full of curious and instructive facts respecting the 
position and distribution of the subterranean waters under and 
near Paris; but it must suffice to say that the report came to 
the conclusion that, in consequence of the absolute immobility 
of these waters, and the relatively small quantity of noxious 
fluid to be conveyed to them, there was no danger of the 
diffusion of such fluid if discharged into them. This result will 
not surprise those who know that, in another work, Duchatelet 
maintains analogous opinions as to the effect of the discharge 
of the city sewers into the Seine or the waters of that river. 
The quantity of matter delivered by them he holds to be 
so nearly infinitesimal, as compared with the volume of water 
of the river, that it cannot possibly affect it to a sensible de- 
gree, and therefore cannot render the Seine water unfit for 
drinking.* , 
Meteorological Hffects of Draining. 
The draining of lakes diminishes the water-surface of the 
soil, and consequently, in many cases, the evaporation from it, 
* Coste found, in his experiments on pisciculture, that the fermentation, 
which takes place in the water of the Seine in consequence of the discharge 
of the drains into the river, destroyed a large proportion of the eggs of fish 
in his breeding basins. Analysis of Seine water by Boussingault in 1855 
detected a considerable quantity or ammonia. 
