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son, does not prove the quantity of rain to have diminished; 
the average flow of water may be unaltered, although a diffe- 
rent distribution of the total quantity may have taken place, 
between the several seasons of the year ; and with respect to 
general impressions on the subject, they would no doubt be 
in general, founded on the circumstance of the two conditions 
of abundant moisture and luxuriant vegetation being com- 
monly found together; the effect being mistaken for the 
cause, and the plentiful rain being considered the consequence 
of the very vegetation which it has produced and nourished. 
Mauritius revels in all the conditions necessary to exube- 
rance of vegetation. With a fertile soil, a genial sun, and a 
humid and stimulating atmosphere, it is inconceivable that 
the conversion of the humidity into rain should be the only 
thing to continue wanting for the completion of one of the 
great works of Providence, namely the preservation and mul- 
tiplication of organic life, in the vegetable creation. We can- 
not suppose the laws of nature to have been so disposed that 
rain is forbidden to fall until some human hand shall have 
first planted and noui’ished trees to invite it. Such a theory 
would be altogether contradicted by the wonderful systems of 
self-regulation and compensation which may be observed in 
all the operations of nature. 
The foregoing considerations seem to shew conclusively 
that trees have little or nothing to do with the quantity of 
rain, and that Mauritius will always receive a fair and suffi- 
cient supply, whether forest exist or whether they be swept 
away altogether. 
The real value of trees, in connexion with the water supply, 
consists in their power of preserving and husbanding the rain 
water after it has fallen. 
When rain falls upon land not sheltered by forests, it rush- 
es down the slopes of the ground, at once, without opposition, 
to the water courses ; they are suddenly swelled into torrents, 
but will soon be left dry, as before. 
The very small quantity of moisture which has time to pe- 
netrate into the parched ground, or which remains upon the 
surface, is quickly dried up by the sun, and the water courses 
