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and are caused by the water entering the deep rents, or 

 fissures in the soil, made by the drought, and passing 

 downward between the soil and the stratum on which 

 it rests, and not readily finding a way out, liquefying 

 and carrying away the soil at the bottom of the slope- 

 The soil composing the slope being softened and un- 

 dermined at the base, and loosened from the stratum 

 on which it rests, slips down by its own weight, and 

 carries everything along with it. 



Another benefit that may be expected to result from 

 the re- wooding of hills, at present only covered with 

 grass, is that the water, being hindered from running 

 off the surface of the ground in floods, as at present, will, 

 by percolating through the soil, be given off gradually, 

 and a regular and abundant supply will be kept up in 

 rivers and streams throughout the year. This is a 

 most important consideration, not only as it will main- 

 tain a supply of water for domestic purposes, cattle, 

 &c, but also as a motive-power for machinery, the 

 irrigation of the land, and in navigating the rivers. 

 Re-wooding large tracts of land will also have the 

 effect of making the climate moist throughout the 

 year, and, in consequence, fit for the growth of agri- 

 cultural produce for which otherwise it would be 

 quite unsuitable, by reason of aridity. For example, a 

 field of rich land may be planted with sugar canes, 

 and well irrigated, but if the climate of the locality 

 be dry and arid, the crop will not pay expenses should 

 the canes grow, which is questionable. It is my 

 opinion that much of the cane disease, so disastrous 

 in Mauritius of late years, is due to the unsuitability 

 of the climate, brought about, or caused, by the over 

 destruction of the forests. It would seem that a pro- 

 portion of unwooded arable land and of forest were 



Q2019. I 



