Chap. I. CONICAL HILL. 47 



To the south my rambles never extended further than 

 the banks of the Irura, a stream which rises amongst 

 the hills already spoken of, and running through a 

 broad valley, wooded along the margins of the water- 

 courses, falls into the Tapajos, at the head of the bay of 

 Mapiri. All beyond, as before remarked, is terra incog- 

 nita to the inhabitants of Santarem. The Brazilian 

 settlers on the banks of the Amazons seem to have no 

 taste for explorations by land, and I could find no per- 

 son willing to accompany me on an excursion further 

 towards the interior. Such a journey would be exceed- 

 ingly difficult in this country, even if men could be 

 obtained willing to undertake it. Besides, there were 

 reports of a settlement of fierce runaway negroes on the 

 Serra de Mururaru, and it was considered unsafe to go 

 far in that direction, except with a large armed party. 

 I visited the banks of the Irura and the rich woods 

 accompanying it, and two other streams in the same 

 neighbourhood, one called the Panema, and the other 

 the Urumari, once or twice a week during the whole 

 time of my residence in Santarem, and made large 

 collections of their natural productions. These forest 

 brooks, with their clear cold waters brawling over their 

 sandy or pebbly beds through wild tropical glens, 

 always had a great charm for me. The beauty of the 

 moist, cool, and luxuriant glades was heightened by the 

 contrast they afforded to the sterile country around 

 them. The bare or scantily wooded hills which sur- 

 round the valley are parched by the rays of the vertical 

 sun. One of them, the Pico do Irura, forms a nearly 

 perfect cone, rising from a small grassy plain to a height 



