REBOISEMENT. Ill 



process. The increasing scarcity of wood for fuel and 

 other economic purposes demanded and received attention, 

 but it was seen that an improved forest economy, whilst 

 it might secure the conservation of existing forests, and 

 the utilising of these to the benefit of the proprietors and 

 of the nation, must be accompanied by a replanting of 

 the mountains of woods where they had been denuded 

 of these, and elsewhere if the threatening calamity was 

 to be averted. 



In 1793 Fabre showed that torrents were attributable 

 to the destruction of forests on the mountains. In 1841 

 Surell showed that torrents appeared and disappeared as 

 forests were destroyed and reproduced. In 1872 Cezanne 

 showed that this relation between forests and floods can 

 be traced from preadamic times to the present. And in 

 1874 Michel Costa de Bastelica traced indications of 

 torrential phenomena in what had been accepted as 

 glacial deposits of times anterior to what Cezanne had 

 designated the torrential era. 



In accordance with these views arrangements were made 

 by the Government of France for an expenditure of ten 

 millions of francs in replanting with trees, and herbage, 

 and bush, ground drained by torrents ; and within ten 

 years torrents which had been most destructive had 

 become placid perennial streams, peaceful as a little 

 child. 



Of one torrent, that of Sainte-Marthe, near Embrun 

 the ravages of which by torrents are spoken of by M. 

 He'recart de Thary in a passage previously cited [p. 86] 

 of this torrent M. Costa de Bastelica, in a treatise 

 entitled Les Torrents, leur causes, leur effets, moyens de les 

 reprimer, et de les utiliser, leur action universelle, published 

 in 1874, writes : 



' In 1841, when M. Surell wrote his famous Etude sur 

 les Torrents des H antes- Alpes,i\\\ torrent had acquired an 

 unenviable celebrity by its violence. It carried away 

 every bridge thrown across its course ; at every storm of 



