FLOODS OF THE ARDECHE. 
389 
eastern elope of the high grounds where the Ardeche and sev¬ 
eral other western affluents of the Rhone take their rise. The 
wind tore up all the trees in its path, and the rushing torrents 
Lore their trunks down to the larger streams, whicli again trans¬ 
ported them to the Rhone in such rafts that one might al¬ 
most have crossed that river by stepping from trunk to trunk.* 
The Rhone, therefore, is naturally subject to great and sudden 
inundations, and the same remark may he applied to most of 
the principal rivers of France, because the geographical char¬ 
acter of all of them is approximately the same. 
The height and violence of the inundations of most great 
rivers are determined by the degree in which the floods of the 
different tributaries are coincident in time. Were all the afflu¬ 
ents of the Rhone to pour their highest annual floods into its 
channel at once, were a dozen Riles to empty themselves into 
its bed at the same moment, its water would rise to a height 
and rush with an impetus that would sweep into the Mediter¬ 
ranean the entire population of its banks, and all the works 
that man has erected upon the plains which border it. But 
such a coincidence can never happen. The tributaries of this 
river run in very different directions, and some of them are 
swollen principally by the melting of the snows about their 
sources, others almost exclusively by heavy rains. When a 
damp southeast wind blows up the valley of the Ardeche, its 
moisture is condensed, and precipitated in a deluge upon the 
mountains which embosom the headwaters of that stream, 
thus producing a flood, while a neighboring basin, the axis of 
* The original forests in which the basin of the Arcteche was rich have 
been rapidly disappearing, for many years, and the terrific violence of the 
inundations which are now laying it waste is ascribed, by the ablest inves¬ 
tigators, to that cause. In an article inserted in the Annales Forestieres 
for 1843, quoted by Ilohenstein, Der Wald , p. 177, it is said that about one 
third of the area of the department had already become absolutely barren, 
in consequence of clearing, and that the destruction of the woods was still 
going on with great rapidity, blew torrents were constantly forming, and 
they were estimated to have covered more than 70,000 acres of good land, 
or one sixth of the surface of the department, with sand and gravel. 
