Chap. VI. MOUTH OF THE TAPAJOS. 233 



breadth, reckoning from the places 2000 miles from 

 its mouth, where the river and its earliest tributaries 

 rush forth between walls of rock through the eastern- 

 most ridges of the Andes. It is, perhaps, necessary 

 to take this in consideration when studying the geo- 

 graphical distribution of the plants and animals which 

 people these vast wooded plains. 



We crossed the river three times between Monte 

 Alegre and the next town, Santarem. In the middle 

 the waves ran very high, and the vessel lurched fear- 

 fully, hurling everjrthing that was not well secured from 

 one side of the deck to the other. On the morning 

 of the 9th of October, a gentle wind carried us along 

 a " remanso," or still water, under the southern shore. 

 These tracts of quiet water are frequent on the irregular 

 sides of the stream, and are the effect of counter move- 

 ments caused by the rapid current of its central parts. 

 At 9 a.m. we passed the mouth of a Parana-mirim, called 

 Mahica, and then found a sudden change in the colour 

 of the water and aspect of the banks. Instead of the 

 low and swampy water-frontage which had prevailed 

 from the mouth of the Xingu, we saw before us a broad 

 sloping beach of white sand. The forest, instead of 

 being an entangled mass of irregular and rank vege- 

 tation as hitherto, presented a rounded outline, and 

 created an impression of repose that was very pleasing. 

 We now approached, in fact, the mouth of the Tapajos, 

 whose clear olive-green waters here replaced the muddy 

 current against which we had so long been sailing. 

 Although this is a river of great extent — 1000 miles 

 in length, and, for the last eighty miles of its course. 



