Ch. V, SOUTH AMERICA. 373 



the influx of the river ofChuchiingn, the place where 

 the Maranon becomes navigable, and where M. de 

 la Condamine first embarked on it, he found its 

 breadth to be one hundred and thirty-five toises: and 

 though this was near its beginning, the lead did not 

 reach the bottom at twenty. eight toises, notwith- 

 standing this sounding was made at a great distance* 

 from the middle of the river. 



The islands formed by the Maranon east of the 

 Napo, terminate at the river Coari, where it again re- 

 unites its waters, and flows in one stream : but here 

 its breadth is from one thousand to twelve hundred 

 toises, or near half a league ; and here the same in- 

 genious gentleman, after taking all possible precau- 

 lions against the current, as he had before at the 

 mouth of the river Chuchunga, sounded, but found no 

 bottom with one hundred and three fathom of line. 

 The river Negro, at the distance of two leagues from 

 its mouth, measured twelve hundred toises in breadth, 

 which being nearly equal to that of the principal 

 river, and some of those we have named, Ucayale, the 

 Madera, and others, were found to be nearly of the 

 same width. 



About one hundred leagues below the mouth of 

 the river Negro, the shores of the Maranon begin to 

 approach each other near the efflux of the river 

 Trumbetas, which part is called the Estrecho de 

 Pauxis, where, as also at the posts of Peru, Gurupa 

 and Macapa, along its banks, and on these east of 

 the rivers Negro and Popayos, the Portuguese have 

 forts. At the Estrecho de Pauxis, where the breadth 

 of the river is near nine hundred toises, the eifect of thp 

 tides may be perceived; though the distance from the 

 sea-coasts be not less than two hundred leagues. This 

 effect consists in the waters, which, vvithoutany change 

 in the direction of their course, decrease in their velo- 

 city, and gradually swell over their banks. The 

 flux and reflux arc constant every twelve hours^ with 

 B b 3 the 



