166 EFFECTS OF FORESTS ON BIVBBS. 



It may be that there is not an inch of its course, or of the courses 

 of its numerous tributaries and affluents, which does not pass 

 many of its sources, channels of capillary dimensions, through 

 which, from time to time, such excess of rainfall has drained off, or 

 may drain off, into its bedj by which the accumulated drainings are 

 drained off into the sea, if they be not absorbed or evaporated by the 

 way. 



It is under this aspect of springs, and streamletss, and rivers, we 

 should look at them while considering the local effect upon them -of 

 forests, or of the destruction of these. 



At a conference which I attended in Swartland, at the Cape of 

 Good Hope, after I had given expression to my views on this subject, one 

 gentleman who was present stated that a neighbour of his had 

 planted on his place twelve trees twenty years before, or twenty trees 

 twelve years before, I do not remember which, and that he did not 

 believe one drop more rain had fallen in the district since these trees 

 had been planted than usually fell before ! And I think it not im- 

 possible that this may have been the case ; but there are other ways 

 besides increasing the quantity of the rainfall in which trees may act 

 upon the humidity of a country, and even on the rainfall in a way 

 beneficial to maa and beast. 



It has frequently been remarked that springs, and streamlets, and 

 rivers, which have flowed permanently in the vicinity of forests have 

 ceased to flow when these forjsts have been destroyed ; nor are cases 

 awanting of their flow having been resumed when, by plantations or 

 natural reproductions, the destroyed trees have been replaced by 

 others ; cases ha?e been cited ; and, while apparently in certain 

 circumstances even the extensive destruction of forests has not 

 perceptibly affected the deposit of moisture over a widely extended 

 region, facts are not awanting illustrative of what has been 

 referred to occuriug on an extended, as well as on a limited, scale. 



The observations made by Mr Draper in regard to undiminished 

 rainfall in America must command acceptance. But along with 

 these we must attend also to the following. 



In the Report of the Commissioners of Agriculture, for 1869, it is 

 stated : — " From all parts of the State of Maine come up the same 

 complaint of the diminished volume of water in the streams, 

 occasioned by clearing off the forests and denuding the hills of trees. 

 The snows are not so heavy, nor so frequent, as they were twenty or 



