284 DEVASTATIONS AND RB«TOBATIONS. 



washed away ; and consequently there is reason to believe that the general 

 boisement of the basin would to a marked degree modify the regime of the 

 river. But as for the questions, — Would such hoisement be a remunerative 

 operation, or is it only possible that it might prove so 1 These are economic 

 questions, the discussion of which has been often taken up, but the final 

 settlement of which is still remote." 



In the Haute Loire, operations of reboisement have been carried on in the 

 p6rimfetre of Megal, measuring upwards of 1440 hectares; and of M6zenc, 

 measuring upwards of 11 36 hectares, and in several other hectares, measuring 

 together 1026 hectares. And in the department of the Loire similar oper- 

 ations have been carried on in nine several p6rimfetres, comprising in all an 

 area of nearly 3000 hectares. 



Sect. IX.. — Dejjartment of Herault. 



In H6rault reboisements et gazonnements ohligatoires have been carried on 

 in some eight p6rimfetres, four of which — Eiols, Mons, Saint-Pons, and 

 Samt-Julien — cover an area of nearly 4,800 hectares. Of the first of these 

 it was reported in 1869 : — 



" The perimetre obligaioire de Biols, declared of public utility by imperial 

 decree of the 13th January 1864, is situated entirely in the commune of 

 Riols, canton of Saint-Pons. The mean altitude is 900 metres. It com- 

 prises 1147 hectares 3 ares, of which 968 hectares 43 ares belong to the 

 commune J 162 hectares 70 ares to sections of the commune; and 15 

 hectares 90 ares to different individuals. 



" The p6rim6tre, shut up by high mountains, has steep slopes, the 

 denuded flanks of which are furrowed by numerous ravines. 



" The mountains of Riol form two distinct groups : the chain of Sommail, 

 with an altitude of from 900 tolOOO metres; and that of Marcon, from 800 to 

 about 900. The slopes vary from 50 to 75 in 100. In general they present 

 a sad and desolate aspect ; there are everywhere meagre pastures, cut up 

 in all directions by ravines, where the eye meets not a single clump of 

 trees, for the wood has by imperceptible degrees disappeared, destroyed by 

 the hand of man, or laid waste by the teeth of sheep. 



" The chain of Sommail is of granitic land ; that of Marcon is cal- 

 careous. 



"The first works undertaken in the p6rim6tre date from the year 1864. 

 At the beginning, the soil was prepared by digging holes, called poiets, from 

 12 to 16 inches across, 12 inches deep, and from 3 feet to 3 feet 6 inches 

 apart. Experience has led to some modification of these proceedings. 

 Now, holes much longer, wider apart, and trenched to a greater depth, are 

 made, which, permitting the roots to take more quickly possession' of the 

 soil, develope vegetation more in the places in which there is little depth 

 of soil prevailing generally. 



" These potets, when 6 or 7 feet apart, are about 40 inches square, and 

 are dug to a depth of 18 or 20 inches. 



" At the altitude at which the operations are carried on, resinous trees 

 and the birch alone can withstand the rigorous temperature and the hioh 

 winds which prevail on these unsheltered plateaux. " 



" Sowing or planting is the mode of operation adopted, according to the 

 4epth of eai-th. Sowings are pfeferable on the plateaux; but they do 

 not succeed well on the elevated steep slopes, on account of the heat of 



