156 



THE LOWER AMAZONS 



grey mountain. Ninety miles beyond Almeyrim stands 

 the village of Monte Alegre, which is built near the sum- 

 mit of the last hill visible of this chain. At this point 

 the river bends a little towards the south, and the hilly 

 country recedes from its shores to re-appear at Obydos, 

 greatly decreased in height, about a hundred miles further 

 west. Twenty-five miles to the south-west of Monte 

 Alegre, high land again appears, but now on the opposite 

 side of the river. This is the northernmost limit of the 

 table-land of Brazil, as the hills of Monte Alegre are the 

 southernmost of that of Guiana. In no other part of 

 the river do the high lands on each side approach each 

 other so closely. Beyond Obydos they gradually recede, 

 and the width of the river valley consequently increases, 

 until in the central parts of the Upper Amazons, near 

 Ega, it is no less than 540 miles. At this point, therefore, 

 the valley or river plain of the Amazons is contracted to 

 its narrowest 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 

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

 to take this in consideration when studying the geogra- 

 phical 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 fearfully, hurling 

 everything that was not well secured from one side of the 

 deck to the other. On the morning of the 9th of October, 

 a gentle v/ind carried us along a * reman so 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 movements 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 vegetation 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 



