200 FOEtlST CULTUBE AlfD 



of sea-breezes renders the more littoral tracts of West 

 and North Australia almost free. But in the econo- 

 my of nature the trees, beyond affording shade and 

 shelter, and retaining humidity to the soil, serve 

 other great purposes. Trees, ever active in sending 

 their roots to the depths, draw unceasingly from below 

 the surface-strata those mineral elements of vegetable 

 nutrition on which the life of plants absolutely de- 

 pends, _and which, with every dropping leaf, is left as 

 a storage of aliment for the subsequent vegetation. 

 How much lasting good could not be effected, then, 

 by mere scattering of seeds of our drought-resisting 

 Acacias, and Eucalypti, and Casuarinas, at the termi- 

 nation of the hot season along any water-course, or 

 even along the crevices of rocks, or over bare sands 

 or hard clays, after refreshing showers ? Uven the 

 rugged escarpments of the desolate ranges of Tunis, 

 Algiers, and Morocco might become woodwJ ; even 

 the Sahara itself, if it could not be conqufjfed and 

 rendered habitable, might have the extent of its oases 

 vastly augmented ; fertility might be secured again" 

 to the Holy Land, and rain to the Asiatic plateau, or 

 the desert of Atacama, or timber and fuel be furnish- 

 ed to Natal and La Plata. An experiment instituted 

 on a bare ridge near our metropolis demonstrates 

 what may be done. 



Not Australia alone, but some other countries, have 

 judiciously taken advantage of the facilities afforded 

 by Australian tree- vegetation for raising woods — an 

 object which throughout the interior might be ini- 

 tiated by rendering this an additional purpose of the 

 expeditions to be maintained in the field for territo- 

 rial and physiographical exploration ; and more, it 



