54 



certain degree of activity in the roots. They lay up a supply of aliment in the wood, 

 which serves to keep them alive at a time when grass and herbs would die, and from the 

 depth to which the roots penetrate, they are able to draw water from deeper strata which 

 never become dry, and may thus be able to endure the driest seasons. The amount of 

 water which plants and trees need to sustain life, depends mainly upon the growth and 

 evaporation. The latter differs in the same plant according to age, size, and location, as 

 well as conditions of soil, amount of light, and motion of the air. We have as yet no 

 reliable results as to the amount of water which different forest plants and trees under 

 various circumstances lose by evaporation. This is a subject which deserves our attention 

 in the highest degree, and furnishes a rich subject for forest experimental stations. While 

 linger found that water would evaporate three times the amount of a plant of the same 

 surface, Schleiden concludes that a forest evaporates at least three times as much water 

 as a water-surface of like area. According to Hartig, a forest evaporates less than free 

 water or wet earth. In hot summer days some plants will evaporate their own weight. 

 In fact, forests afford, and some species of trees, more than others, a kind of vertical 

 drainage of water from the soil. 



" With respect to the relative amount of water falling in the fields and forests, it was 

 found uniformly greater at the surface of the earth in the former than the latter, for the 

 manifest reason that a part was intercepted by and evaporated from the foliage of the 

 trees. The percentage in the woods as compared with the fields, varied in different years, 

 by seasons, from forty to ninety, being on the general average of all stations, and, for the 

 whole period least in spring and most in winter. These results will be found to agree 

 with those obtained at other stations, and the rule would doubtless apply to all countries 

 arid to every period of time. 



"The^ foregoing statements show how closely related in a country, are its wealth in 

 forests and water (as shown by the great influence of the former), and the litter that 

 covers the surface, to the evaporation and moisture. It therefore need not surprise us 

 that springs and brooks dry up or flow only periodically, and that the mean height of 

 water in rivers and large streams lessens when large surfaces are cleared up, or that 

 springs flow more abundantly and regularly when, by replanting, the extent of forests 

 is increased. The influence of forests, and of litter-covering on the moisture of the soil, 

 founded upon these observations, may be expressed not only in percentages, but we 

 may be allowed to draw conclusions from small to great, as they afford the means for 

 estimating the loss of water in the soil, caused by large clearings and the taking off of 

 litter from any given surface." 



As I am endeavouring to present in this compilation as good an idea as is available 

 of what has been done in this matter of late years, -in different countries, (for the 

 world in general appears to be becoming aware of the loss of its timber), I will now 

 give an opinion relative to the Indian forests from a source which should command 

 attention. It is from a valuable work entitled " India in 1880," by Sir Richard Temple, 

 Bart., G.C.S.I., C.I.E., D.C.L., late Governor of Bombay, Lieutenant-Governor of 

 Bengal, and Finance Minister of India (a work with which, by the way, I was furnished 

 by the kindness of Mr. Goldwin Smith) : — 



Of his qualifications for writing such a work, the author says ; — " If, in undertaking 

 to give such a description from my own knowledge, I shall seem presumptuous, I may 

 state that the demands of public duty have compelled me to visit every part of the Indian 

 Empire, from Thibet to Ceylon, from the Khyber Pass to the frontier of Ava, from the 

 valley of Asam to the city of Candahar. It has been my fate to serve in the three Presi- 

 dencies of Bengal, Madras, and Bombay, and in every province of the empire with one 

 exception, to be brought in contact with the Native States and the North- West frontier 

 and to be employed in some capacity or other under all the departments of the State'. 

 These circumstances are mentioned in order to show how the materials have been acquired 

 upon which this volume is founded. I have, with trifling exceptions, not only beheld^but 



