274 MAN AND NATURE. 



it together, dried and pulverised by sun and wind, and at 

 last exhausted by new combinations. . . . The rivulets, 

 wanting their former regularity of supply, and deprived of 

 the protecting shade of woods, are heated, evaporated, and 

 reduced in their summer currents, but swollen to raging- 

 torrents in autumn and spring. . . . 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 luxuriance of aquatic 

 vegetables that breeds fever and more insidious forms of 

 mortal disease by its decay. 1 



Such, somewhat abridged, is the theme of our 

 American Evelyn ; in style rather florid and ambitious, 

 yet doubtless containing much that is true and of prac- 

 tical value. He recurs to this topic in every part of 

 the volume, and fortifies his position by various autho- 

 rities, ancient and modern. 2 Here, nevertheless, we 

 must bring in the old claim of audi alter am partem, as 

 essential to truth. Mr. Marsh bestows his zeal on one 

 side of the case, and generalises too much upon it, 

 without duly regarding those many exceptions which 

 Nature is ever suggesting or forcing upon us. He seems 

 to forget in his large conclusions that to preserve the 

 native forest is in many countries to narrow the space 

 allotted by Providence to the growth and maintenance 



1 To these various effects of forest vegetation our author might per- 

 haps have added its influence on the electrical relations of the atmosphere 

 and earth an influence greater, we believe, than is usually supposed. 

 But though certain as fact, the particular conditions it involves are still 

 so little known that their omission may reasonably be justified. 



2 One of the most recent and valuable works on this subject seems 

 to be that of Hohenstein (I860), entitled <Der Wald.' Our old English 

 writer, Harrison, has a curiously quaint chapter on the woods and 

 marshes of England, complaining much of the decay of the former j and 

 other ancient English authorities might be quoted to the same effect. 



