LAWS REGULATING RBBOISEMBNT. 239 



valleys ; that at the entrance to some of these — ^that of Urbage, for example 

 — it does not exceed 1400 or 1500 mfetres (the forest of St Vincent), whilst 

 higher up, round the lake of Parouard, it reaches about 2500 mfetres. 



" The limit is not always the same, but it varies in the same valley 

 following its direction — in a word, the upper limit of forest vegetation is 

 regulated by the local climate, and will change with it. In general, it may 

 be admitted that the summits of the Alps are bare, exposed as they are to 

 all the winds ; that the upper limit of forest vegetation rises wherever the 

 forest is sheltered from the north, and where it can receive the influence of 

 the south wind. 



" I now come to the cultivated zone. In the French Alps this has 

 suffered the most ; to the primitive gentle slopes have succeeded, at many 

 points, more or less terrible erosions, which increase every year ; it is in 

 this zone that the most awful havoc is caused by torrents descending from 

 above. It is there that villages and fields are sometimes carried away, and 

 sometimes buried under the mud, to which by analogy the name of lava 

 is given. In a word, it is the cultivated zone which suffers the havoc caused 

 by the blindness and apathy of the dwellers in the higher districts. It is 

 here that the torrents may be obstructed by artificial obstacles, doubtless 

 insufficient to arrest their ravages permanently, but which may permit us 

 to await without great danger the restoration of the upper districts." 



From this it will be seen that forests still exist, and that to such an 

 extent as to be the characterestic feature of a broad and widely-extended 

 zone in the Alps, where there are forests of an extent of which few 

 untravelled students of arboriculture can form any conception. In the 

 Vosges the extent and the conservative influence of the forests is such, 

 that we have seen M. Surell boldly declaring that a writer on torrents, 

 familiar only with torrents as seen there, evidently did not know what 

 torrents were. 



Chap. III. — Laws Ebgulating the Eeboisement Effected and 

 Measures Adopted. 



The work of reboisement which has been and is being carried on in 

 mountainous regions of France must not be confounded with the work of 

 sylviculture in the Landes, and in the district of the Gironde. The object 

 aimed at, and the system of operations adopted in each of these enter- 

 prisesj is different from those of the other. The latter, advocated by 

 Br^montier, was begun in 1787; it was interrupted in 1789, resumed in 

 1791 ; abandoned in 1793, and begun again in 1801, from which time it 

 has been prosecuted without interruption, and with most satisfactory 

 results. The object aimed at was to arrest and utilize the dunes, or drift 

 sands of Gascogny and adjacent lands. Though still commanding attention, 

 it may be spoken of as the work of the first half of the present century ; 

 the work of reboisement has been the work of the latter half of the century. 

 Originating from the publication of the Mude sur les Torrents des Hautes 

 Alpes, by M. Surell, it has for its object to arrest the destructive effects of 

 these. 



As stated by M. Magne, in his report to the Emperor, of which a trans- 

 lation was previously given (ante pp. 147-152) between 1843 and the date 

 of his report, February 1860, "sixty-three general councils have urged the 

 necessity of measures being taken for the reforesting of the mouptains, A 



