46 ASPECTS OF TROPICAL NATURE 



mountain-group in the Llanos, and conveys part of the waters 

 of the Orinoco to the Amazons, as if the latter were not already 

 sufficiently 'great. After a course of 1500 miles it throws 

 itself into the vast stream, 3600 paces broad and 19 fathoms 

 deep. Brigs of war have already ascended the Amazons as 

 far as the Rio Negro, and frigates would find no obstacle in their 

 way. 



The Madeira, the next great tributary of the regal stream, 

 has thus been named from the vast quantities of drift-wood 

 floating on its waters. Three considerable rivers (two of which, 

 the Mamore and the Beni, issue from the Andes, while the third, 

 the Gruapore, arises in the Campos de Parecis, but fifteen miles 

 from the sources of the Paraguay), form the enormous Madeira, 

 which rolls its waters slowly through the plains, as if, conscious 

 of being among the largest of rivers, it unwillingly stooped to 

 minister to the greatness of a still mightier stream. 



After the influx of the Madeira, the Amazons frequently swells 

 to a breadth of seven miles, and hollows its bed to an average 

 depth of twenty-four fathoms. Farther on, after having with a 

 side-arm embraced the island of Tupinambaranas, which almost 

 equals Yorkshire in extent, the Amazons now reaches the famous 

 strait of Obydos, where it narrows to 2126 paces, and rolls 

 along between low banks in a bed whose depth as yet no 

 plummet hath sounded. The mass of waters which, during the 

 rainy season, rushes in one second through the strait, is estimated 

 by Von Martins at 500,000 cubic feet, — enough to fill all the 

 streams of Europe with an exuberant current. 



The tides extend as far as Obydos, though still 400 miles 

 from the sea ; and, according to La Condamine, they are even 

 perceptible as far as the confluence of the Madeira. But so 

 slow is their progress upwards, that seven floods, with their 

 intervening ebbs, roll simultaneously along upon the giant 

 stream ; and thus, four days after the tide-wave was first raised 

 in the wide deserts of the South Sea, its last undulations expire 

 in the solitudes of Brazil.* 



The next considerable vassal of the Amazons is the shallow 

 Tapajo^l^Hjkh, however, is preferred to the Madeira for water- 

 commuiM^^ between the provinces of Matto-Grosso and 



* "The Sea and its Living "Wonders." Second Edition, p. 41. 



