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(i) The case "Forest Destruction does diminish the rainfall ": 
I think that the few authors about to be cited are fairly representative of 
the evidence that is usually adduced. There is a certain amount of vagueness in 
some cases as to whether it is intended to state that the amount of rainfall is 
diminished by the destruction of trees. My first illustration is given, because in 
one version or another it is so often quoted in the periodical discussions that have 
taken place in New South Wales. 
The most fertile of all provinces in Bucharia was that of Sogd. Malte Brun 
said, in 1826 : 
For eight days we may travel and not be out of one delicious garden. 
In 1876, another writer says of the same region : 
Within thirty years this was one of the most fertile spots of Central Asia, a country which, when 
well wooded and watered, was a terrestrial paradise. But within the last twenty-five years a mania for 
clearing has seized upon the people, all the great forests have been cut away, and the little that remained 
was ravaged by fire during the civil war. The consequences followed quickly, and this country has been 
transformed into a kind of arid desert. The watercourses are dried up, and the irrigating cannls are 
empty. 
It is certain that the fertility of these regions in ancient times was due to stupendous irrigating 
devices and canals, and when these were neglected, through wars and other untoward circumstances, the 
fertility necessarily ceased. It is certain that there are ruins of enormous irrigating ditches and canals in 
Babylonia where history indicates that there was ones a teeming population and great fertility, but where 
now only a sandy desert greets the eye.* 
The late Sir William Hooker wrote : 
That from Ascension there continued to be received encouraging accounts of the increased fertility 
and moisture of the island consequent on the extension of the plantations, f 
It is proper to point out that in this statement it is not asserted that the 
rainfall is alleged to have been increased. 
It is remarked by Marsh, that " It has long been a popularly settled belief that vegetation and 
condensation and fall of atmospheric moisture are reciprocally necessary to each other, and even the poet 
sings of 
Afric's barren sand, 
Where nought can grow, because it raineth not, 
And where no rain can fall to bless the land, 
Because nought grows there. 
Here we have an illustration of the converse fact ; one measure of humidity promoting vegetation, and 
vegetation not only arresting the desiccation, but so reversing the process that an increased humidity is the 
consequence. J 
While the extract just quoted may be interpreted as not stating that forests 
increase rainfall, the same work contains many instances (not well classified) of 
the effects of the destruction of the forests and of varying degrees of value, but 
affording a lengthy list fronuwhich a writer working up a case can obtain his 
illustrations. 
In connection with the systematic destruction of timber in Australia, it is mentioned that in the 
Ballarat district this destruction has been accompanied by a corresponding diminution in the rainfall, and 
since 1863 there has been a more or less regular reduction, from 37 '27 inches in 1863 to 14-23 inches in 
1868. 
* I'rofessor H. A. Hazen before Annual Meeting of American Forestry Association, Nashville, Tenn., U.S.A., 22nd 
September, 1897 ; quoted in " Nature," 30th December, 1897, p. 213. 
t Report of the Director of Kew Gardens for 18(H. 
t J. Croumbie Brown's " Forests and Moisture," pp. 144-5. 
"Nature," i, 261. 
C 
