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 exprefsly upon this fubject, 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 aflures 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 bafHed the inquiry of alk 
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 pofli- 
bility. M. de la‘Chambre fays, that the nitre with which 
the ground in Egypt is impregnated,.ferments like a kind 
of pafte, 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 thofe attempts 
with which the ancients endeavoured to folve thofe phe- 
nomena, when, for want of a fufficient progrefs in experi: 
mental philofophy and obfervation, they were generally 
deftitute of the proper means; but there is no excufe for a 
man’s either believing or writing, that earth, impregnated 
with fo {mall 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 fuch 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 
thar 
