230 France. 



1,000,000 acres' in extent, of mountain slopes, is ex- 

 posed to the ravages of these waters by erosion. 



Here the most forcible demonstration of the value 

 of a forest cover in protecting watersheds was 

 furnished by the results of the extensive forest 

 destruction and devastation which took place 

 especially during and following the years of the 

 Revolution. 



Long ago, in the 16th century, the local parliaments 

 had enacted decrees against clearing in the moun- 

 tains, with severe fines, confiscation and even corporal 

 punishment, and these restrictions had been generally 

 effective; but during the Revolutionary period all 

 these wholesome restrictions vanished; inconsiderate 

 exploitation by the farmers began, and the damage 

 came so rapidly that in less than ten years after the 

 beginning of freedom, the effect was felt. Within 

 three years (1792), the first complaints of the result of 

 unrestricted cutting were heard, and, by 1803, they 

 were quite general. The brooks had changed to 

 torrents, inundating the plains, tearing away fertile 

 lands or silting them over with the debris carried 

 down from the mountains. Yet in spite of these 

 early warnings and the theoretical discussions by such 

 men as Boussingault, Becquerel and others, the des- 

 tructive work by axe, fire and over-pasturing pro- 

 gressed until about 8 000,000 acres of tillable land had 

 been rendered more or less useless, and the population 

 of 18 departments had been impoverished or reduced 

 in number by emigration. 



A young engineer, Swell, was the first to study the 

 possibility of coping with the evil and proved in his 



