INFLUENCE OF THE FOREST ON PRECIPITATION. 191 
Yosges and Ardennes produce the same effects in the north¬ 
east of France, and send us a great river, the Meuse, which is 
as remarkable for its volume as for the small extent of its 
basin. With respect to the retardation of the atmospheric 
currents, and the effects of that retardation, one of my illus¬ 
trious colleagues, M. Mignet, who is not less a profound 
thinker than an eloquent writer, suggested to me that, to pro¬ 
duce rain, a forest was as good as a mountain, and this is 
literally true.” 
Monestier-Savignat arrives at this conclusion : “ Forests on 
the one hand diminish evaporation ; on the other, they act on 
the atmosphere as refrigerating causes. The second scale of 
the balance predominates over the other, for it is established 
that in wooded countries it rains oftener, and that, the quan¬ 
tity of rain being equal, they are more humid.” * 
Boussingault—whose observations on the drying up of 
lakes and springs, from the destruction of the woods, in trop¬ 
ical America, have often been cited as a conclusive proof that 
the quantity of rain was thereby diminished—after examining 
the question with much care, remarks : “ In my judgment it 
is settled that very large clearings must diminish the annual 
fall of rain in a country ; ” and on a subsequent page, he con¬ 
cludes that, u arguing from meteorological facts collected in 
the equinoctial regions, there is reason to presume that clear¬ 
ings diminish the annual fall of rain.” f 
The same eminent author proposes series of observations on 
the level of natural lakes, especially on those without outlet, 
as a means of determining the increase or diminution of pre¬ 
cipitation in their basins, and, of course, of measuring the 
up in greate heapes in the feeldes, and to looke vpon, they were like vnto 
mountaynes; for the raine, the whyche hadde beaten vpon the wheate now 
a longe whyle, had made it to sproute on the toppe, so that it seemed as 
greene grasse. And whanne they were mynded to carrie it to Egypte, 
they brake that sod of greene herbe, and dyd finde under the same the 
wheate and the barley, as freshe as yf menne hadde butnowe thrashed it.” 
* &tude sur les Ecolx au point de vue des Inondations , p. 91. 
t Economie Rurale , ii, chap, xx, § 4, pp. 756-759. See also p. 733. 
