USE OF WOODS IN THE ECONOMY OF NATURE. 177 



be in the highest degree endangered. United together, 

 they mutually shelter each other on all sides against storms 

 and the drying effect of the sun's rays. This reciprocity 

 of action is highly interesting. Thus, herbaceous plants 

 and grasses envelope the earth with a protective covering. 

 They allow the sunbeams access to the young seedlings, 

 and also give them a sufficient amount of shade, so that 

 the sun's rays are prevented from drying the soil, and thus 

 injuring their young life. It is thus that trees grow up at 

 first under the shadow of the smallest members of the 

 vegetable kingdom, only to reciprocate, as they approxi- 

 mate to the period of their maturity and strength, the favors 

 which they received in the hour of weakness and infancy. 

 Under their summits the shadowed earth retains its mois- 

 ture, and the poorer plant-children of Nature are thus fed, 

 whose tender rootlets have not the ability, like the roots of 

 trees, to draw their moisture deeply out of the earth. 

 Besides, a moss-carpet forms on the ground in woods, at 

 least in temperate and cool climates, which preserves the 

 soil moist much longer, or lets it slowly penetrate to the 

 deeper lying basins among the hills. So also, when showers 

 of rain fall on forests, the leaves of the trees catch the drops, 

 break the force of their descent, and the plants thus shel- 

 tered gently drink in the moisture of the storm, whilst they 

 escape its violence. The moss-covering, too, retains the 

 moisture long after the storm has passed and sun-smiles 

 brighten the earth, whilst the shadow of the trees prevents 

 its evaporation. 



It follows that a wooded soil is favorable to the production 

 of springs ; also, that the continued existence of moisture 

 in woods and the constant evaporation from them will pro- 

 duce a cooler atmosphere, and therefore a lower degree of 

 temperature in a country where they abound. It is not 

 difficult to make this intelligible to the reader. The ocean, 

 winds, and woods, may be regarded as the several parts of 

 a grand distillatory apparatus. The sea is the boiler in 

 which vapor is raised by the solar heat, the winds are the 

 guiding tubes which carry the vapor with them to the 

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