5C2 Periodical Inundations. [Book VII. 



ings are purfued, and delineated, in prejudice of fome 

 other branch that better deferved the name and the 

 defcription. In this manner*, in Europe, the Da- 

 nube is known to receive thirty leffer rivers; the 

 Wolga thirty-two or thirty- three. In Afia, the Ho- 

 hanno receives thirty-five; the Jenifca above fixty; 

 the Oby as many ; the Amour about forty ; the Nan- 

 quin receives thirty rivers ; the Ganges twenty j and 

 the Euphrates about eleven. In Africa, the Senegal 

 receives more than twenty rivers ; the Nile receives 

 not one for five hundred leagues upwards, and then 

 only twelve or thirteen. In America, the river Ama- 

 zons receives above fixty, and thofe very confiderable ; 

 the river St. Lawrence about forty, counting thofe 

 which fall into its lakes ; the Miffiffippi receives forty ; 

 and the river Plata above fifty. 



The inundations of the Ganges and the Nile have 

 -been already mentioned, and it might be added, that 

 aim oft all great rivers have their periodical inundations 

 from fimilar caufes. The author already quoted ob- 

 ferves, that, fc befides thefe annually periodical inunda- 

 tions, there are many rivers that overflow at much 

 fnorter intervals. Thus moft of thofe in Peru and 

 Chili have fcarce any motion by night; but upon the 

 appearance of the morning fun they refume their 

 former rapidity: this proceeds from the mountain 

 fnows, which, melting with the heat, encreafe the 

 ftream, and continue to drive on the current while the 

 fun continues to difiblve them -f .' 



There are fome rivers which are faid to lofe them- 

 felves in chafms under the earth, and to flow for fe- 



veral miles in fecret and undifcovered channels. On 

 i 



* Buffon, vol. ii. p. 74. 



f Goldfmith's Earth, p. zeo. 



" this 

 ; 4^ , 



