674 FRAVELS' FO DISCOVERT 
the quantity of mud which the Nile brought down by its. 
inundation, which fo covered the land-marks, that’ no 
proprietor knew or could difcover the limits of his own. 
farm, and that this annual neceflity firft gave rife to the: 
{cience of Geometry *. _How or when Geometry was firft 
known and pra¢tifed, is not my bufinefs in this place to 
inquire, though I think the origin here given is a very 
probable one. The land of Egypt was certainly meafured’ 
annually : it is as certainly fo at this very time ; and if fo, the 
prefent reafon for this is probably the very one which firft 
gave rife to it; but that this is not owing to the mud of the 
Nile, will appear on the flighteft confideration ; for if Egypt 
increafe a foot in a hundred years, one year’s increafe of foil: 
could be but the one hundredth part of a foot, which could 
hide no land-mark whatever; and we fee to this day thofe. 
in Egypt were huge blocks of granite often with gigantic. 
heads at the end of them; which the Nile, at the rate Hero- 
dotus fixes, of a foot in 100 years, as being added to the foil). 
would not cover in feveral thoufand years. 
Ir is abfurd to fuppofe that the Nile is to bring down: 
an equal quantity of foil every year from the mountains: 
of Abyffinia ; whatever was the cafe at firft when this river- 
began to flow, we are fure now, that almoft every ri-. 
ver and brook in Abyffinia runs in a bed of hard ftone, 
the earth having been long removed; and the rivers now 
cannot furnifh from their rocky beds what they firft did 
from their earthy bottoms, when Egypt was fuppofed, ac- 
cording to Herodotus, to have its foundation laid in the 
floods ; 
* Terod, lib. ii. p. 127. fe&. 109. 
We hd 
