EFFECTS OF FOEEST VEaETATIOK ON CLIMATE. 183 



vegetable treasures has destroyed the character of Nature, and 

 terrified man himself flies from the arena of his actions, leaving 

 the impoverished earth to barbarous razees or animals, so long as 

 yet another spot in virgin beauty smiles before him. 



" Here again in selfish pursuit of profit, and conscioiisly or 

 unconsciously following the abominable principle of the great 

 moral vileness Avhich one man has expressed apres nous le deluge^ 

 he begins anew the work of destruction." (Henfrey's Schleiden's 

 Eleventh Lecture, p. 304-6.) 



There is much in this reasoning of the G-erman professor 

 which agrees with the sentiments of the late Sir Henry Holland, 

 Bart., who in an able critical essay in the Tldraburgli Mevieio of 

 1864, of Marsh's excellent work "Man and Nature," says: — 

 " It is the forest w^hich actively ministers to the climatic con- 

 ditions of the earth, which, extirpated by the axe or restored by 

 planting, changes both the face of nature and the distribution 

 and destinies of human life." The simple name of Forest will 

 hardly bring to the casual reader a conception of all that it 

 implies ; of the vast extent of the earth's " surface thus covered 

 in every zone to the very confines of the Arctic Circle-; of the 

 various aspects and qualities of this great forest mantle, and of 

 its relation to all the moving elements of the natural world. It 

 is impossible to estimate, even by loose approximation, the actual 

 extent of surface so occupied. We have given reasons for 

 believing that the earth was largely covered with wood at the 

 time when man first became its denizen." Mr. Marsh himself 

 enters most minutely into the use and value of Eorest vegeta- 

 tion, and describes with accurate care the effects consequent on 

 the clearing of his native American lands by the axe or the 

 prairie fire: — "With the disappearance of the forest all (he 

 says) is changed. At one season the earth parts with its warmth 

 by radiation to an open sky, and receives at another heat from 

 the unobstructed rays of the sun. Hence the climate becomes 

 excessive, and the soil is alternately parched by the fervour of 

 summer and seared by the rigours of winter. Bleak wdnds 

 sweep unresisted over its surface, drift away the snow^ that 

 sheltered it from the frost, and dry up its scanty moisture. . . . 

 The washing of the soil from the mountains leaves bare ridges 

 of sterile rock, and the rich organic mould which covered them, 

 now swept down into the damp low grounds, promotes a luxu- 

 riance of aquatic vegetables that breed fever and more insidious 

 forms of mortal disease by its decay." — ("Man and Nature, or 

 Physical Greography as modified by Human Action." By Grcorge 

 P. Marsh. 1864.) 



The review^er of this enthusiastic w^ork points out wdiere the 

 author leans too partially to one side of his argument, but fairl}^ 

 joins him in affirming that " vegetation, under the form of woods, is 



