258 FORESTRY IN FRANCE. 
buildings are either thrown down or overwhelmed, the railways and 
roads are blocked, and the bridges are overthrown, while the fields 
are completely and irretrievably destroyed. The damage thus 
caused is most serious, both in its nature and extent; and to it 
must be added the great inconvenience and loss occasioned by 
the interruption of traffic on the roads and railways. But this is 
not all. If the débris transported by the torrent is carried into 
the river before it can be deposited, it is either borne on at once 
and thrown on to the level country lower down, or it remains, and 
turns the course of the stream over the fields and buildings on its 
opposite bank. Occasionally the deposit temporarily blocks up the 
valley, and causes the inundation of villages and fields on the 
upper side of the barrier ; and when this latter ultimately gives 
way, the most disastrous results ensue, both in the lower part of 
the valley, and in the open country at the foot of the mountain 
range. It is to mitigate these terrible evils that the vast enterprise 
of afforesting the mountains has been undertaken as the only means 
of dealing with them. But, owing to the enormous cost of the 
works, it cannot be hoped that the forests thus raised will ever 
prove directly remunerative, and their creation, with a view to their 
ever becoming so, could not for a moment be justified. 
The works are of two classes, viz.: (/vrstly), The treatment of 
‘the torrent beds by a series of weirs and other structures, destined 
to bring them gradually, and by successive stages, to a normal 
slope, and thus, not only to prevent “scour,” but, by the filling up 
and widening of the beds behind the weirs, to afford support to the 
unstable sloping sides, and thus gradually to consolidate them, 
with a view to their being ultimately planted up. (Secondly), The 
immediate planting up of all areas, the surface of which does not 
seem likely to be washed down within the period occupied by the 
construction in that locality of the first class of works. A com- 
mencement was made in 1860; but the law passed in that year 
not having been found sufficient, a new law came into force in 
1882, which provides both for the works to be undertaken directly 
by the State, and for those to be executed by the proprietors of the 
ground, with or without State aid, as well as for simple measures 
of prevention. 
Works undertaken by the State.—The proposal to take up ground 
for this purpose emanates from the Forest Department, and is 
followed by a formal enquiry, under the direction of the Prefect, 
into the circumstances of the case, regarding which a special com- 
