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TORRENT OF ST, MARTIN 

 Large barrage, crushed for the fourth time by lateral pressure 



by aspen and alder cuttings which have 

 been planted to hold the loose soil on 

 the slope as much as possible. (How 

 any human being ever kept himself on 

 those hillsides to do the planting with- 

 out wings is a mystery.) These early 

 attempts at planting, however, do not 

 appear to be very successful and proba- 

 bly will not be until the slope has ac- 

 quired the "angle of repose." 



In the case of Les (jorgettes, floods 

 still occur and carry away parts of 

 some of the "barrages," and the steep 

 slopes are still crumbling down into the 

 torrent. But it is considered that 

 further cutting down of its bed by the 

 torrent has been checked and that there- 

 fore the first and most dangerous part 

 of the work is over. The final step 

 will be to reforest the slopes as soon as 

 they become sufficiently permanent. 



Thus, after a long period of years, 

 through terribly hard and often dan- 

 gerous work, and the expenditure of 

 large sums of money, the forest about 

 this stream bed may be brought to what 

 it was before private individuals were 

 given a free hand. 



Unfortunately the case of Les Gor- 

 gettes is simple compared with some of 

 the others. In a different part of the 

 mountains not far from Grenoble, near 

 the quaint little village of Vaujany, is a 



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torrent called Les Aiguilles, meaning 

 "The Needles" on account of its numer- 

 ous sharp points. All attempts to con- 

 trol this torrent have failed, and the 

 cutting will have to be allowed to con- 

 tinue till the slopes have worn them- 

 selves down to a more gentle angle. 



2. Bodily slipping of large masses. 

 The best example seen of this difticult 

 proposition was the torrent of St. Mar- 

 tin. This is in Savoy near the famous 

 Mount Cenis pass through the Alps into 

 Italy. The torrent rises in a steep 

 basin at about 8,000 feet elevation. 

 Howing through rather gently sloping 

 pastures and then down a steep pitch 

 into the main river at about 3,000 feet, 

 a total drop of about 5,000 feet. The 

 great difiiculty occurs where it would 

 least be expected. The large innocent 

 looking pastures are composed of a 

 kind of loose slatey gypsum soil which 

 becomes saturated with water, causing 

 large areas to sli]) in a body gradually 

 but irresistibly downward toward the 

 banks of the stream. Of the "barrages" 

 built in the bed of the torrent one of 

 the largest, eighteen feet high by ten 

 feet thick, had been crushed and re- 

 built three times and when seen had 

 been crushed again for the fourth time 

 by the terrific lateral pressure. The 

 numerous smaller "barrages" had been 



