Page:Travels to Discover the Source of the Nile - In the Years 1768, 1769, 1770, 1771, 1772, and 1773 volume 3.djvu/698

 674             TRAVELS TO DISCOVER

the quantity of mud which the Nile brought down by its inundation, which so covered the land-marks, that no proprietor knew or could discover the limits of his own farm, and that this annual decessity first gave rise to the science of Geometry*. How or when Geometry was first known and practised, is not my business in this place to inquire, though I think the origin here given is a very probable one. The land of Egypt was certainly measured annually: it is as certainly so at this very time; and is so, the present reason for this is probably the very one which first gave rise to it; but that this is not woing to the mud of the Nile, will appear on the slightest consideration; for if Egypt increase a foot in a hundred years, one year's increase of soil could be but the on hundredth part of a foot, which could hide no land-mark whatever; and we see to this day those in Egypt were huge blocks of granite often with gigantic heads at the end of them; which the Nile, at the rate Herondorus fixes, of a foot in 100 years, as being added to the soil, would not cover in several thousand years.

It is absurd to suppose that the Nile is to bring down an equal quantity of soil every year from the mountains of Abyssinia; whatever was the case at first when this river began to flow, we are sure now, that almost every river and brook in Abyssinia runs in a bed of hard stone, the earth having been long removed; and the rivers now cannot furnish from their rocky beds waht they first did from their earthy bottons, when Egypt was supposed, according to Herodorus, to have its foundation laid in the

floods;


 * Herod, lib. II.P. 127 ...