102 
Professor Ilazen has some further remarks that are pertinent in this connec- 
tion ; and, as his paper is one of the ablest contributions to the subject that I have 
read, I would like to again quote him : 
It has been said that where our densest forests are found, that we have the greatest precipitation. 
There is no way whereby we can see that such forests would have started unless favoured by rainfall, so 
that the presence of the forest rather indicated the earlier occurrence of practically the same rainfall as at 
present. Meteorologists are agreed that there has been practically no change 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 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 leaves 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 l)e 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. 
Let me again quote Bibbentrop : 
Forests can have no influence whatever on the amount of moisture drawn from the ocean, and the 
general direction of the winds is unquestionably governed by greater causes. But, apart from this, 
periodical rains are subject to the same general laws as all other rains, and must, therefore, be, affected by 
the same causes, and amongst them by extensive forest growth, in exactly the same way and degree. The 
may be charged with moisture, which need not, however, be precipitated.* 
Let me quote the same author to again emphasise the point that, while it is 
indubitably true that rainfall conditions mainly originate many very many miles 
from the scene of deposit, it is simply impossible, and, indeed, undesirable, to lose 
sight of the local contributing effects of forests : 
The climate of each country and of each district is primd facie dependent upon its geographical 
position, its'elevation, the configuration of the ground, and other cosmic causes, which are independent of 
local circumstances. It can hardly be denied that the existence or non-existence of large well-wooded 
areas in a country naturally capable of growing forests, affects its climate in a very marked degree. 
History proves this to us in numerous instances where the deterioration of the climate of whole districts, 
and even of whole countries, has followed the destruction of forests.f 
4. 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 large tree may 
mechanically hold, for a considerable time, a large quantity of water ; and if this be 
multiplied indefinitely, as in a forest, an enormous quantity of water will be held or 
retarded. The effect of transpiration will be dealt with below. 
* Op. cit,, p. 45, t /*., p. 40. 
