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trees grew up the water coming to the brook was so regulated as 

 to serve its former useful purpose in driving the mills, and the 

 torrents in winter were moderated. Several other examples of a 

 similar character are given. 



In Switzerland, amongst other examples is quoted one that 

 occurred in the canton of Berne, where, owing to the re-planting 

 of the mountain-side with fir trees, the water again appeared at 

 a spring which had ceased to flow. After a period the trees were 

 cut down and the land converted into pasturage, since when the 

 spring has almost disappeared only opening out at occasional in- 

 tervals. 



In the Kazan district of Russia, once celebrated for its forests 

 of oaks and linden, which are now nearly all cut down, there were 

 formerly seventy water-mills constantly at work. Less than half 

 now can be worked, and even they only run half time, and are 

 idle in summer for want of water ; while in winter the little rivers 

 that worked these mills are converted into impetuous torrents, 

 breaking up the mill dams and doing other damage. These aban- 

 doned water-mills stand out as a striking proof of the conse- 

 quences of the destruction of forests. 



In Sardinia, where the surface consists of plutonic rocks covered 

 with a thin layer of earth, all the streams have a rapid slope. The 

 woods, which occupied in 1870 an area of more than 2h million 

 acres, or about 43 per cent, of the whole surface of the island, 

 now are reduced to about one-sixteenth of this area. Since the 

 removal of the trees the floods in the rivers rise with a rapidity 

 and flow with a velocity never known before, and a great number 

 of bridges have been destroyed by the floods. The beds of the 

 channels have been raised in some places above the surface of the 

 land, owing to the detritus brought down in floods. 



In Wisconsin, U.S.A., the settlers cut down the forests and con- 

 verted the land into tillage and pasture. During a period of about 

 seventy years nearly the whole of the forest land was thus cleared 

 with the result that, as the forest disappeared, the water in the 

 river became lower; finally thirty miles of the channel entirely 

 dried up, and many water-mills that were formerly worked by the 

 stream are now deserted and useless, owing to the want of water 

 to run them. 



In Sicily, owing to the cutting down of the forests on a vast 

 scale in the province of Messina, the bed of the river has been 

 raised by the stones and earth carried down by the torrents so as 

 to stop all drainage from the land, and great damage has been 

 done by the floods. Several other examples are given to the same 

 effect where forests have been cleared in the same district, and 

 these are compared with other streams where the forests still exists 

 and their condition remains unaltered. In the former case, land- 

 slides from the mountains have become very frequent. 



