THE SOURCE OF THE NILE. 663 



* 



becaufe we are now perfectly certain, from obfervation, that 

 Democritus and Agatharcides both of them had fallen upon 

 the true caufes of the inundation. 



I shall now mention a treatife of a modern philofopher^ 

 wrote expreisly upon this fubjecl, I mean a difcourfe on the 

 caufes of the inundation of the Nile, by M. de la Chambre, 

 printed at Paris in quarto, 1665, where, in a long dedica,- 

 tion, he modeftly allures the king, he is perfuaded that his 

 majefty will confider, as one of the glories of his reign, the 

 difcovery of the true caufe of the Nile's inundation, which 

 he had then made, after it had baffled the inquiry of all 

 philofophers for the fpace of 2000 years ; and, indeed, the 

 caufe and the difcovery would have been both very remark- 

 able, had they been attended with the leaft degree of poili- 

 bility. M. de la Chambre fays, that the nitre with which 

 the ground in Egypt is impregnated, ferments like a kind 

 of pafle, occafioning the Nile to ferment likewife, and thus 

 increafes the mafs of water fo much, that it fpreads over 

 the whole land of Egypt. . 



Far be it from me to bear hard upon th'ofe attempts 

 with which the ancients endeavoured to folve thofe phs*- 

 nomena, when, for want of a fufficient progrefs in experi- 

 mental philofophy and obfervation, they were generally 

 deilitute of the proper means ; . but there is no cxcufe for a 

 man's either believing or writing, that earth, impregnated 

 with fo fmall a quantity of any mixture as not to be dif- 

 cernible to the eye, fmell, or tafte, could periodically fwell 

 the waters of a river, then almoft dry, to fucli an immen- 

 fity, as to cover the whole plains of Egypt, and difcharge 

 millions of tons every day into the fea, at the fame time 



that 



