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be checked and that eventually the erosion of the ground was manifested, at first in an 

 insignificant and protracted manner, then by degrees in a more and more rapid form. At 

 present, the mantle of verdure which covers the mountains still acts as a powerful brake 

 on torrential action, but if we are to allow what remains of forest to be destroyed, and the 

 mountain grasslands to be burnt and grazed indiscriminately, the ruin of much of the 

 land will become a matter of years, and perhaps it would not then be feasible to spend 

 millions in redeeming it. While it is in our power to avert such consequences, we should 

 profit by the experience that has been so dearly bought elsewhere, and not neglect to 

 adopt any reasonable protective measures. Besides being cheaper, it is also better to pre- 

 serve natural forests than destroy them to substitute plantations which take centuries to 

 acquire the deep layer of humus and the surface growth which give such a peculiar 

 climatic value to the natural forest. 



Torrential action at the Cape is also manifest, though in a milder form than in Natal, 

 In a recent report published in the Cape Government Gazette, Prof. J. R. Seeley writes, 

 speaking of the Cape : " When, too, land has been denuded of its timber, the water 

 sweeping over the country carries away the ground which should have been under culti- 

 vation. This process is going on to an extent of which few people have any conception, 

 and the result is that land is being destroyed in a wholesale way, for it is not merely the 

 breaking up of the land which is so serious, but that a line of drainage is created deep 

 beneath the surface of the country/' 



INFLUENCE OF FORESTS ON WATER SUPPLY. In a forest country, the minor streams 

 appear in striking contrast dried up or perennial, according to whether they issue from 

 a forest or from the open, though the drainage areas and the rainfall may beequal in 

 both cases. This connection between forests and the volume of water delivered by springs 

 is a matter of common observation, established by innumerable instances, of which there 

 is no need to give any examples. Evidence on this point may be found in Marsh's work 

 on " The Earth as Modified by Human Action." M. Comte-Granchamps estimates that 

 in coniferous forests of the Loire and the Alps, the normal delivery of a water-course is 

 increased by 229 cubic feet daily for each acre reforested in its basin, and by 57 cubic 

 feet for each acre grassed. If the springs decrease their flow as the forests are destroyed, 

 the rivers which they feed must also shrink in volume. In 1873, G. Wex proved in an 

 able and exhaustive work that the volume of water delivered by the five principal rivers 

 of Central Europe namely the Danube, the Rhine, the Elbe, the Vistula, and the 

 Oder has in each case decreased continually for a long period (of years, and he ascribes 

 this effect to a corresponding diminution of forests. Commissions appointed in Austria 

 and in Russia to report on this work confirmed the conclusions arrived at by the author, 

 and the Russian Commission adds that the Volga has also diminished in volume in conse- 

 quence of the cutting down of the great forests on the Ural Mountains. 



