388 
FLOODS OF THE AEDECHE. 
This is equal to 323,222,400 cubic yards per day. In a single 
day of flood, then, the Ardeche, a river too insignificant to be 
known except in the local topography of France, contributes 
to the Rhone once and a half, and for three consecutive days 
once and one third, as much as the average delivery of the 
Nile during the same periods, though the basin of the latter 
river contains 500,000 square miles of surface, or more than 
five hundred times as much as that of the former. 
The average annual precipitation in the basin of the Ar¬ 
deche is not greater than in many other parts of Europe, but 
excessive quantities of rain frequently fall in that valley in the 
autumn. On the 9th of October, 1827, there fell at Joyeuse, 
on the Beaume, no less than thirty-one inches between three 
o’clock in the morning and midnight. Such facts as this ex¬ 
plain the extraordinary suddenness and violence of the floods 
of the Ardeche, and the basins of many other tributaries of 
the Rhone exhibit meteorological phenomena not less remark¬ 
able.* The inundation of the 10th September, 1857, was 
accompanied with a terrific hurricane, which passed along the 
into the Mediterranean by the Mile in twenty-four hours, at low water, is 
150,566,392,368 cubic metres; at high water, 705,514,667,440 cubic metres. 
Taking the mean of these two numbers, the average daily delivery of the 
Mile would be 428,081,059,808 cubic metres, or more than 550,000,000,000 
cubic yards. There is some enormous mistake, probably a typographical 
error, in this statement, which makes the delivery of the Mile seventeen 
hundred times as great as computed by Talabot, and many times more 
than any physical geographer has ever estimated the quantity supplied by 
all the rivers on the face of the globe. 
* The Drac, a torrent emptying into the Is£re a little below Grenoble, 
has discharged 5,200, the Is&re, which receives it, 7,800 cubic yards, and 
the Durance an equal quantity, per second.— Montluisant, Note sur les 
JDessechements , etc ., Annales des Fonts et Chaussees , 1833, 2me semestre, 
p. 288. 
The floods of some other French rivers scarcely fall behind those of the 
Rhone. The Loire, above Roanne, has a basin of 2,471 square miles, or 
about twice and a half the area of that of the Ardeche. In some of its 
inundations it has delivered above 9,500 cubic yards per second.— Bel- 
grand, Be VInfluence des Forets , etc., Annales des Fonts et Chaussees , 1854, 
ler sSmestre, p. 15, note. 
