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Mr. Chitten- have maintained that precipitation has been diminished in particular 
den. —_ localities by the destruction of forests, or augmented by planting them, 
has led the public to suppose that their assertions rested upon suflicient 
proof. I cannot affirm that in none of those cases did such proof exist, 
but I am not aware that it has ever been produced.” 
Perfectly applicable is this statement to the common theories of 
the present day. 
It is also claimed that precipitation is more irregular, but here 
again evidence is lacking, and, such as there is, is conflicting. There 
is nothing of sufficient duration or accuracy to enable one to draw 
positive conclusions, except that whatever changes may have resulted 
are of very small magnitude. The distribution of rainfall throughout 
the year is very irregular, and upon this fact Mr. Leighton and others 
have built up their theory of increased flood frequencies following de- 
forestation. It might possibly be claimed that this irregularity itself 
is due to deforestation, but this is negatived by the fact that the 
greatest irregularity in the numerous records cited by Dr. McGee and 
Mr. Leighton occurred on those water-sheds where there had been the 
least change in those years in forest areas. 
The claim often advanced, that broad general changes in climate 
have resulted from changes wrought by Man on the surface of the 
earth in particular localities, is likewise without.substantial founda- 
tion. The writer believes that a careful study of the question, with 
the same rules of evidence that would be applied to any other subject, 
will convince any one of the substantial correctness of the following 
statement by Professor Cleveland Abbé, of the U. S. Weather Bureau, 
in his article on climate in the International, Encyclopedia: 
“There is no well-authenticated case of an appreciable change of 
climate within the past two thousand years. The researches of 
Eginitis on the climate of Greece seem to establish this principle be- 
yond doubt. Neither is it possible that any change on the surface of 
the earth due to man—such as deforestation, reforestation, agriculture, 
canals, railroads, or telegraph lines—can have had anything more than 
the slightest local effect, if any, on climatic phenomena that depend 
upon the action of the whole atmosphere.” 
One of the most common of popular fallacies is this belief in 
change of climate. In every community probably the majority of peo- 
ple believe that material changes have occurred within a generation. 
Most of us can remember when it was generally thought that the cli- 
mate of Western Nebraska and Kansas was changing, and rain was be- 
coming more frequent as a result of settlement and cultivation. A 
succession of more than average wet years was responsible for this be- 
lief, and many settlers moved to that country on the strength of it. 
But after a while normal conditions returned—perhaps the pendulum 
swung the other way—and many a settler was forced to leave the 
country. These facts are matters of official record. 
