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made with great care and complete sets of instruments at 

 different stations, seem to establish the facts, first, that 

 throughout the year six per cent, more rain falls in the forests 

 than in the open fields ; second, that of the total rainfall ten 

 per cent, in the forest is caught by the leaves and reaches the 

 earth very gradually, or not at all ; and, third, that the evap- 

 oration in the open country is five times as great as in a 

 forest. 



But on the question of the influence of forests on climate 

 and the permanent water supply, there is a growing unanimity 

 among practical foresters and professors in the forest schools 

 of Europe. Their theories and observations plainly show 

 that the wholesale clearing of forests has an injurious effect 

 on both, while the extensive planting of trees on arid regions 

 has ameliorated the climate, prevented mountain torrents, and 

 rendered the water supply more permanent. These investi- 

 gations show that the general destruction of forests has ren- 

 dered the climate dryer, more changeable and trying, and that 

 forests on the one hand tend to lower the general temperature 

 of a country and promote the fall of rain at more i-egular in- 

 tervals, and on the other hand they ward off sudden meteor- 

 ological changes which result in heavy falls of rain and 

 disastrous floods. 



It is well known that houses too closely surrounded by trees 

 are damp. Beautiful and healthful as shade trees are, they 

 may stand too near the house. Dense evergreens growing so 

 close as to shut out all sunlight, are harmful. It is an old 

 Italian proverb, that " where the sunlight cannot come the 

 doctor must;" and sometimes the wisest direction of the 

 physician to his rheumatic patient is, to cut down the tree 

 which too densely overshadows the house and excludes all 

 sunlight. The wetness of roads completely overshadowed by 

 trees, shows how forests affect the humidity of the ground 

 they cover. Mr. Marsh says : " One important conclusion at 

 least is certain and undisputed, that within their own limits 

 and near their own borders forests maintain a more uniform 

 degree of humidity in the atmosphere than is observed in 

 cleared grounds." Speaking of the indiscriminate clearing in 



