Page:A discourse upon the origin and foundation of the inequality among mankind (IA discourseuponori00rous).pdf/259

 as to tart Difficulties to the Suppoition of this natural Fertility of the Earth, I hall endeavour to obviate them by the following Paage.

"As Vegetables derive for their Support a great deal more Subtance from the Air and Water than from the Earth, o, when they decay, they retore to the Earth more than they received from it; moreover, Forets engros great Quantities of Rain Water by topping the Vapours that form it. Thus, in Woods that have remained untouched for a long Time, the Layer of Earth, in which the Buines of Vegetation is carried on, mut have received a coniderable Addition. But Animals retoring to the Earth les than they derive from it, and Men conuming enormous Quantities of Vegetables for firing and other Purpoes, it follows that the Layer of vegetating Earth, in well peopled Countries, mut be contantly on the Decline, and become at lat like the Surface of Arabia Petrea, and o many other Provinces of the Eat, (which in Fact is the Part of the World that was earliet inhabited)