342 THE BOOK OF THE LANDED ESTATE. 



immediately covered on the outside with dew-drops of moisture ; whence come these ? 

 Not through the glass from the water within, but from the atmosphere without a 

 proof that the moisture was there though unseen. 



It may have been observed that the hotter an iron plate may be, the more 

 quickly is any water spilt upon it converted into vapour. The reason is, the more 

 rapidly does it impart the heat necessary to the vaporisation of the fluid. So is it 

 with the soil ; the hotter the soil may be, the more rapidly is moisture evaporated. 



There is always a difference in the temperature of soil exposed to the direct rays 

 of the sun and the temperature of soil in the shade, whether that shade be afforded 

 by roof, rock, tree, or bush, or even by the grass. 



Thus can we in part account for what has been seen to follow the destruction ot 

 bush, whether it be for a supply of fuel, or in connection with the burning of the 

 veldt as a means of securing pasturage, desired for flocks or herds. The principle 

 involved is equally applicable to the destruction of trees. 



Such are the opinions of Dr Brown, and those who may have given 

 some attention to the subject will agree with him. It is an import- 

 ant fact that the denudation of a country has been followed by an 

 increase of heat and drought from the destruction of forests of trees 

 and bush ; and there can be no doubt that if portions of those countries 

 which I refer to were judiciously clothed with plantations, consisting of 

 kinds of trees suited to the soil and climate, they would ere long be very 

 much improved, in respect to a better supply of water and the fertility 

 of vegetation. 



We have ample proof from geology that Syria and Persia were at one 

 time covered with masses of wood, and that there were streams, flowing 

 throughout these countries, which are now completely dried up. Por- 

 tions of these countries were once thickly populated, but now, from the 

 want of water, the inhabitants are much fewer in number. 



In Jamaica the clearing of forests has been followed by a diminution 

 of water. 



The great missionary Moffat tells us, in reference to his settlement at 

 Latakoo, that the natives used to speak of the floods of ancient times, 

 and the incessant showers which clothed the very rocks with verdure, 

 and the extensive forests, consisting of giant trees, which once studded 

 the brows of the hills. They spoke with rapture of the large rivers, 

 with their impassable torrents, in which the hippopotami amused 

 themselves, while herds of other animals walked to their necks in luxu- 

 riant grass, filling their makukas (milk-sacks) with milk, making all 

 their hearts to sing with joy. The remains of these large forests were 

 found in numbers of large stumps of the Acacia giraffe; but at the 

 time of Mr Moffat's settlement there was hardly one of the kind to be 

 found, while the hills and ancient beds of rivers plainly told that they 

 were covered at a former period with a more luxuriant herbage than now 

 clothes them, the whole country north of the Orange river, lying east 



