IMPEDIMENTS TO NAVIGATION. 261 



srhat are called rapids (raudalcs). Such are the yellalas, or 

 rapids of the River Zaire,* or Congo, which Captain Tuckey 

 has recently made known to us ; the rapids of the Orange 

 liiver in Africa, above Fella ; and the falls of the Missouri, 

 which are four leagues in length, where the river issues 

 from the Rocky Mountains. Such also are the cataracts of 

 Atures and Mavpures; the only cataracts which, situated 

 in the equinoctial region of the New World, are adorned 

 M ith the noble growth of palm-trees. At aD seasons they 

 exhibit the aspect of cascades, and present the greatest 

 obstacles to the navigation of the Orinoco, while the rapids 

 of the Ohio and of Upper Egypt are scarcely visible at the 

 period of floods. A solitary cataract, like Niagara, or the 

 cascade of Terni, afibrds a grand but single picture, varying 

 only as the observer changes his place. Rapids, on the 

 contrary, especially when adorned with large trees, embel- 

 lish a landscape during a length of several leagues. Some- 

 times the tumultuous movement of the waters is caused 

 only by extraordinary contractions of the beds of the rivers. 

 Such is the angostura of Carare, in the river Magdalena, 

 a strait that impedes communication between Santa Fe do 

 Bogota and the coast of Carthagena; and such is thepongc 

 of Manseriche, in the Upper Maranon. 



The Orinoco, the Rio Negro, and almost all the con- 

 fluents of the Amazon and the Maranon, have falls or rapids, 

 either because they cross the mountains where they take 

 rise, or because they meet other mountains in their course. 

 If the Amazon, from the pongo of Manseriche (or, to speak 

 with more precision, from the pongo of Tayucluu-) as far as 

 its mouth, a space of more than seven hundred and fifty 

 leagues, exhibit no tumultuous movement of the waters, the 

 river owes this advantage to the uniform direction of its 

 course. It flows from west to east in a vast plain, forming 



* Voyage to explore the River Zaire, 1818, pp. 152, 327, 340. What 

 the inhabitants of Upper Egypt and Nubia call chelldl in the Nile, is called 

 yellala in the River Congo. This analogy between words signifying 

 rapids is remarkable, on account of the enormous distance of the yellalas 

 of the Congo from the chelldl and djenadel of the Nile. Did the word 

 chellal penetrate with the Moors into the west of Africa? If, with 

 Burckhardt, we consider the origin of this word as Arabic (Travels in 

 Nubia, 1819), it must be derived from the root chtUla, ' to disperse,' which 

 forms chelil, ' water falling through a narrow channel.' 



