386 
FLOODS OF THE AKDECHE. 
valleys and plains of France, than to the perils and losses of 
the Lombard. The writings of the Italian hydrographers, too, 
though* rich in professional instruction, are less accessible to 
foreigners and less adapted to popular use than those of French 
engineers.* For these reasons I shall take my citations prin¬ 
cipally from French authorities, though I shall occasionally 
* allude to Italian writers on the floods of the Tiber, of the Arno, 
and some other Italian streams which much resemble those of 
the rivers of England and the United States. 
b. Floods of the Ardeche. 
The floods of mountain streams are attended with greater 
immediate danger to life and property than those of rivers of 
less rapid flow, because their currents are more impetuous, and 
they rise more suddenly and with less previous warning. At 
the same time, their ravages are confined within narrower 
limits, the waters retire sooner to their accustomed channel, 
and the danger is more quickly over, than in the case of inun¬ 
dations of larger rivers. The Ardeche, which has given its 
name to a department in France, drains a basin of 600,238 
acres, or a little less than nine hundred and thirty-eight square 
miles. Its remotest source is about seventy-five miles, in a 
straight line, from its junction with the Rhone, and springs at 
an elevation of four thousand feet above that point. At the 
lowest stage of the river, the bed of the Chassezac, its largest 
and longest tributary, is in many places completely dry on the 
* The very valuable memoirs of Lombardini, Cenni idrograji sulla 
Lombardia , Intorno al sistema idraulico del Po, and other papers on simi¬ 
lar subjects, were published in periodicals little known out of Italy; and the 
Idraulica Pratica of Mari has not, I believe, been translated into French 
or English. These works, and other sources of information equally inac¬ 
cessible out of Italy, have been freely used by Baumgarten, in a memoir 
entitled Notice sur les Rivieres de la Lombardie , in the Annates des Pouts 
et Chaussees , 1847, ler s6mestre, pp. 129 et seqq., and by Dumont, Des 
Travaux Publics dans leurs Rapports avec VAgriculture, note, viii, pp. 269 
et seqq. For the convenience of my readers, I shall use these two articles 
instead of the original authorities on which they are founded. 
