EVILS FOLLOWING DESTRUCTION OF FOKESTS. 89 



And these present moreover at the same time so much 

 resistence to be overcome, and are so much support given 

 to the maintenance of the equilibrium of stability ; acting 

 in the same manner as do sustaining piles, which aie 

 sometimes fixed in slopes, which are too mobile and too 

 steep, in order to prevent landslips ; and thus do these 

 numberless firmly rooted trunks retain the snowfields on 

 all surfaces covered with them. Such is the mechanical 

 action of the forest of piles devised by the genius of 

 Gaubert to protect the military hospital of Bareges 

 against the avalanches by which it is threatened. And 

 without more than a moments pause we may tell that 

 these piles employed as expedients designed to meet the 

 requirements of the moment, have been followed by 

 efficient reboisements, and the construction of barrages, 

 which have produced the happiest results. 



' The protective efficiency of forests has been put pro- 

 minently forward by all authors who have written on the 

 subject. In their interesting work, entitled Les Glaciers, 

 MM. Zurcher and Margolle remark (p. 192) : "The village 

 of the St. Gothard owes its preservation to a small forest 

 of fir-trees situated on the brow of the mountain which 

 dominates it, and thus this forest has become for the 

 inhabitants an object of the greatest care. They have 

 surrounded it with a hedge to prevent the access of cattle, 

 and very severe penalties have been decreed for men who 

 may be guilty of the least damage to these sacred trees." 



' The same fact is mentioned by Viollet-le-Duc in his 

 Etude du Massif du Mont Blanc. 



'M. Philippe Breton, engineer-in-chief of roads and 

 bridges, charged with the special service of the Etudes des 

 Torrents des Alpes, after having cited an example of the 

 influence of forests on the extinction of avalanches in the 

 basin of La Romanche, adds: "This example proves, 

 then, two things : (1) In certain localities the effect of a 

 good forest system may suppress, or at least greatly reduce, 

 the damage done by avalanches, and this simple reduction 

 may suffice to avert grievous consequences; (2) we find 



