FORESTS IN THEIR RELATION TO RAINFALL. 223 



in the climate of the world since the earliest mention of such 



climates When we come down to recent times and 



to the records of rainfall measured in New England (U.S.A.) for 

 more than one hundred years, or at least, before and since the 

 forests were cut, we find a constancy in the rainfall which shows 

 its entire independence of man's efforts. Here it should be noted 

 that totally barren lands of any extent, in New England for 

 example, are to be found only in imagination. Even where the 

 forests have been cut away mercilessly there springs up a growth 

 of sprouts which covers the ground, and answers almost the same 

 purpose in causing rainfall (if there is any effect of that kind) as 

 the forests. Even where land is entirely cleared of a forest we 

 have at times the green pasture and at others still heavier crops 

 which leave the soil anything but a sandy waste." 



Professor Harrington, a learned meteorologist, also says: 

 "The facts to hand do not prove, with entire conviction, that 

 forests increase the rainfall. The historical method is lacking 

 generally in the character of the data for the beginning of the 

 comparison. Besides, where a change of rainfall has been actually 

 shown to be coincident with a change in the forest growth it is 

 not entirely certain that the former is due to the latter; it may 

 have been due to what are called secular changes of the rainfall, 

 the reasons for which lie beyond our knowledge. The geographical 

 method is not entirely satisfactory, for reasons already mentioned. 

 The entirely convincing method depends on observations above 

 forests and with systems of radial stations as proposed by Dr. 

 Lorenz Liburnau, and from these there is not a sufficient amount 

 of published results." 



IV. Clouds may Strike Against Trees and Deposit 

 Moisture. 



Trees cause a distribution of moisture from clouds, where 

 bare surfaces do not cause precipitation, but allow the 

 clouds to roll on. A single tree mechanically holds, for a 

 considerable time, a large quantity of water and if this be 

 multiplied indefinitely as in a forest, an enormous quantity 



