O THE ANCIENT EGYPTIANS. CHAP. XI. 



obviously occurred to them ; and if it be true, 

 that Menes, their first king, turned the course 

 of the Nile into a new channel he had made for 

 it, we have a proof of their having, long before 

 his time, arrived at considerable knowledge in this 

 branch of science, since so great an undertaking 

 could only have been the result of long experience. 

 These dykes were succeeded or accompanied by 

 the invention of sluices, and all the mechanism 

 appertaining to them ; the regulation of the supply 

 of water admitted into plains of various levels, the 

 report of the exact quantity of land irrigated, the 

 depth of the water and the time it continued 

 upon the surface, which determined the pro- 

 portionate payment of the taxes, required much 

 scientific skill ; and the prices of provisions for the 

 ensuing year were already ascertained by the un- 

 erring prognostics of the existing inundations. This 

 naturally led to minute observations respecting the 

 increase of the Nile during the inundation : Ni- 

 lometers, for measuring its gradual rise or fall, 

 were constructed in various parts of Egypt, and 

 particular persons were appointed to observe each 

 daily change, and to proclaim the favourable 

 or unfavourable state of this important pheno- 

 menon. On these reports depended the time 

 chosen for opening the canals, whose mouths were 

 closed until the river rose to a fixed height *, 



* Pliny says, *' Nilus ibi coloni vice fungens, evagari incipit, ut clixi- 

 nius, a solstitio aut nova Luna, ac prinio lente, deinde vehementius, 

 quamdiu in Leone sol est. Mox pigrescit in Virginem transgresso, 

 atque in Libra residet. Si duodecim cubita non excelsit fames certa 

 est : nee minus si sedecim exsuperavit." . . . . " Vulgo credebatur ab 



