PRACTICAL FORESTRY. 



CHAPTER I. 

 INFLUENCE OF FORESTS ON CLIMATE. 



The influence of forests on climate, is a subject that 

 has attracted the attention of all civilized nations, and 

 barbarous races, however low in the scale of intelligence, 

 know enough of the effect of forests on climate to seek 

 or avoid them as may be necessary to escajie disease, or 

 obtain shelter. AVe are not, however, to suppose that 

 large forests are always a blessing to a country or to a 

 people, or that their total absence is in all cases a dire 

 calamity, for the jungles of India, or the almost im- 

 penetrable forests of the tropical regions of America, are 

 no more desirable as places of residence, than the arid 

 plains of this or any other country. What man should 

 seek, is adaptation of the climate to his needs, and if he 

 can increase or decrease the amount of moisture by chang- 

 ing the area covered by forest, he should lose no time in 

 beginning to raise trees, or to destroy them, which ever 

 is likely to conduce most to his welfare. 



The cutting down of great forests, thus allowing the 

 air and sun to reach the earth, and the wind to sweep 

 over its surface, must necessarily hasten the disappear- 

 ance of moisture therefrom, just as the opening of the 

 windows of a room tends to a more rapid movement of 

 the air within, and aids in dispelling smoke, steam, or 

 odors which it may have previously contained. We ven- 

 tilate a building by arranging for the ingress and egress 

 of air in such a way that it shall be kept in motion, and 

 (9) 



