FOEEST LANDS FOR THE PROTECTION OF WATERSHEDS. 107 



the Cevennes, and 44 square miles in the Pyrenees. The expenditure has been 



as follows : 



For acquisition of land $5,200,000 



For work of reforesting 4,000,000 



For work of regulating 2,600,000 



Miscellaneous '. 1, 600, 000 



Total 13. 400, 000 



and there is still to be expended under the plan contemplated about $23,000,000 

 more. 



Referring to this work one of the most recent writers on the subject (G. 

 Huffel, Economie Forestiere, 1904) states: "The role of the forest as a regu- 

 lator of the flow of streams may be considered as evident, and it is to-day uni- 

 versally admitted." Under the able direction of Prosper Demontzey, chief of 

 the service of reforestation in France for 1882 until retired in 1893, and of his 

 predecessors, much has been accomplished, and some formerly very destructive 

 torrents have been reduced to inoffensive streams by reforestation and regula- 

 tion, much more being expended for reforestation than for regulation, as above 

 shown. Perhaps it will now be argued that the good results that have fol- 

 lowed have been due entirely to the regulation and not to the reforestation, but 

 that is not the view of the French engineers. 



At first there was great opposition to he French governmental policy on the 

 part of the inhabitants of the mountain districts, and in 1864 there were riots 

 in some places. This opposition, however, has entirely subsided, the inhabitants 

 now cooperate heartily with the Government, even petitioning to have it extend 

 its work, and in some cases even giving portions of their lands on the mountain 

 sides without compensation. 



When it comes to the question of extreme droughts, Colonel Chittenden takes 

 a curiously contradictory position to the one which he takes in considering the 

 matter of floods. Regarding the latter, it will be remembered, he considers that 

 the forests may cause a combination of the highest floods arising simulta- 

 neously from different tributaries : with reference to droughts, however, he 

 assumes just the reverse, namely, that the extreme low water on different tribu- 

 taries will not occur simultaneously. It seems clear that the extreme combina- 

 tion is as likely to occur in one case as in the other. 



He admits "that, as a general rule, springs and little streams dry up more 

 completely than when forests covered the country," but he argues that, since 

 each spring is small, their drying up will have little effect upon the main 

 stream, the flow of which will be kept up, if the region is deforested, by the 

 rapid discharge, over the surface, of the water from summer showers, which 

 will occur, first on one tributary and then on another, in such a way as to fur- 

 nish to the main stream always a low-water flow greater than if the springs 

 could all be kept np. If his argument be carried to the very common case where 

 no rain falls upon a given drainage basin for weeks, or for a much longer time 

 than it takes for a drop of water to flow from the extreme source to the mouth, 

 it would seem to lead to the conclusion that there would be no flow at all in 

 the stream. In* other words, the author would ha-ve the mills at Lawrence and 

 Lowell depend for their summer flow, not upon keeping up the " springs and 

 little streams" so far as possible by increasing through the effect of forests the 

 percolation into the ground, but .would have these mills trust to luck that the 

 summer showers would be so distributed over the different tributary basins 

 that when one was low others would be high, and he maintains that in this 

 way the low water would be greater than if all the little springs were kept up. 

 This would, of course, require most intelligent planning on the part of Jupiter 

 Pluvins, for it would not do to have these summer showers, which are sup- 

 posed to flow rapidly from the surface, inaccurately timed or distributed over 

 the basin. It does not seem necessary to pursue this suggestion further. 



Even a large drainage area, say 10,000 square miles, may well have its main 

 stream possess a length from extremest source to mouth, measured on the 

 stream, of considerably less than 300 miles. If the average velocity of the 

 stream is 1 mile an hour, which is low. it would take less than two weeks for 

 a drop of water to pass from the extremest source to the mouth. Now, even in 

 districts which have a summer rainfall, it frequently happens that even an area 

 as large as that mentioned is without rain in any part of it for months at a 

 time, under which condition, if the writer understands Colonel Chittenden's 

 theory and his admission, even such a large stream would practically dry up. 



