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substratum water stands at a lower level on forest land than on the adjacent cleared ground. The fact is 
generally to be admitted to be the case at one period of the year. As the result of many years' observa- 
tions, it has been found that the maximum level of underground water is reached in May, that the water 
accumulates in the ground from August to January, and that the rivers are supplied by this reserve ; and 
were it not for this accumulation many brooks and river feeders would cease to flow in summer. 
Several very striking examples are given by the authors of the papers as to the deleterious effect of 
cutting down forests, especially in hilly districts. In the commune of La BruguuTe the forests on the 
slopes of the Black Mountain were cut down ; the consequence of this removal of the trees was that a 
brook which ran at the foot, and the water from which was used for driving some fulling-mills, became so 
dried up in summer as no longer to be of any use, while in winter the sudden floods caused very great 
damage in the valley. The forests were replanted, and as the trees grew up the water coining to the brook 
was so regulated as to serve its former useful purpose in driving the mills, and the torrents 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 Borne, where, owing to. the replanting 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 intervals. 
In the Kazan district of Bussia, 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 abandoned water-mills stand out as a standing proof of the consequences 
of the destruction of forests. In Sardinia, where the surface consists of plutonic rocks, with a thin layer 
of earth, all the streams have a rapid slope. The woods, which occupied in 1870 an area of more than 
two-and-a-half 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 converted 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, 30 miles of 
the channel entirely dried up, and many water-mills that were formerly worked by the stream are now 
eserted and useless, owing to the want of water to run them. In Sicily, owing to the cutting down of 
ie 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 
clone 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 exist, and their 
condition remains unaltered. In the former case, land-slides from the mountains have become very 
frequent.* 
(b) To conserve Springs, and to aid in the more even distribution of 
Terrestrial Waters. 
These subjects are intimately associated with the preceding, the necessity for 
the tempering of the floods being only an extreme case of the conservation and 
distribution of water. 
Under the forest shade, the soil is in a state of perpetual increment from the humus afforded by 
'^raying foliage, and trunks and roots hold it together; the branches break the violence of the rainfall ; 
the spongy absorbent nature of the soil enables it to retain it ; and this, slowly sinking into the 
underlying rock, preserves the needful moisture in the soil, and becomes the source of perennial springs. 
But if such a mountain forest be suddenly laid low, we have not only to fear the appearance of an 
undergrowth prejudicial to tree reproduction, but wo have to fear the total loss of the soil, which exposed 
to the violence of the falling ruin and no longer held together by the tree-roots, gots washed down into the 
valley below, until the bared subsoil or rock is unfitted for the support of any but the scantiest herbage.! 
* Agrtc, Journal, Cape of Good Hope, May, 1900, pp. 613- G15. t Amery, " Notes on Forestry," p. 12. 
