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Mr. Emerson describes the uses of forests as follows : — 



1. Forests create, or gradually but constantly improve a soil. 

 The roots penetrate deeply into the ground, and thus let in the 

 air, to produce its slow but sure effects. The radicals decompose 

 the grains of sand, and extract from them some of the elements 

 essential to a soil ; they drink in moisture and the carbonic acid 

 gas, which has been formed beneath or brought down from the 

 atmosphere above the surface ; and from these several elements, 

 acted on by heat, light and air, in the leaves and by that un- 

 known influence, vegetable life, are formed the various substances 

 which compose the plant. The annual deposit of leaves and the 

 final decay of the branches and trunk, go to constitute the mould 

 upon which other plants grow. And the soil thus formed is kept 

 by the thick matting of the roots from washing away. 



2. Another use of forests is to serve as conductors of elec- 

 tricity between the clouds and its great reservoir, the earth, thus 

 giving activity to the vital powers of plants, and leading the 



clouds to di'scharge their contents upon the earth The 



forests also coat the earth and keep it warm in winter, shutting in 

 the central heat, which would otherwise more rapidly radiate into 



space and be lost Forests act not less favorably as a 



protection against the excessive heat of the summer's sun, which 

 rapidly evaporates the moisture and parches up the surface. . . . 



3. Forests protect a country from the violence of winds 



The laws of the motion of the atmosphere are similar to those of 

 water. A bare hill gives no protection. The wind pours over it 

 as water pours over a dam. But if the hill be capped with trees, 

 the windy cascade will be broken as into spray. Its violence will 



be sensibly diminished A garden, surrounded by tall 



trees, admits the cultivation, even in our severe climate, of plants 

 almost tropical. 



Forests not only protect from Avinds ; they must prevent their 

 formation. The air, resting over a broken surface, cannot be 

 rapidly heated to a uniformly high temperature, so as to rise up- 

 wards in great masses and create a violent wind.* 



* A writer in the sixth volume of the New England Farmer says : — " It is 

 indeed astonishing how much better cattle thrive in fields even but moder- 

 ately sheltered, than they do in an open, exposed country. In the breeding 

 of cattle, a sheltered farm, or a sheltered corner in a farm, is a thing much 



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