XX] LONDON: VOYAGE TO SINGAPORE 317 



mountains of Guiana, and, perhaps, in some parts up to the 

 foot of the Andes. The other great peculiarity of the river 

 is its dark brown, or nearly black, waters, which are yet per- 

 fectly clear and pleasant to drink. This is due, no doubt, to 

 the greater part of the river's basin being an enormous forest- 

 covered plain, and its chief tributaries flowing over granite 

 rocks. It is, in fact, of the same nature as the coffee-coloured 

 waters of our Welsh and Highland streams, which have their 

 sources among peat-bogs. A delightful peculiarity of all these 

 black or clear water rivers is that their shores are entirely free 

 from mosquitoes, as is amusingly referred to in my brother's 

 letter, already quoted in Chapter XVIII. 



After my journey the river Uaupes remained unknown to 

 the world for thirty years, when, in 1881 and 1882, Count 

 Ermanno Stradelli, after spending two years in various parts 

 of the Amazon valley, ascending the Purus and Jurua rivers, 

 visited this river to beyond the first cataracts. Having fever 

 he returned to Manaos (Barra), and joined an expedition to 

 determine the boundary between Brazil and Venezuela through 

 an unknown region, and descended the Rio Branco to Manaos. 

 He then went a voyage up the Madeira river, returning home 

 in 1884. In 1887 he again visited South America, ascending 

 the Orinoko, passed through the Cassiquiare to the Rio Negro, 

 and having become much interested in the rock-pictures 

 he had met with in various parts of these rivers, he again 

 made a voyage up the Uaupes, this time penetrating to the 

 Jurupari cataract, which I had failed to reach, and going about 

 a hundred miles beyond it This last voyage was made in 

 1 890- 1 89 1. His only objects seem to have been geographical 

 and anthropological explorations, and he has probably ex- 

 plored a larger number of the great tributaries of the Amazon 

 and Orinoko than any other European. 



For a knowledge of this great traveller I am indebted to 

 Mr. Heawood, the librarian of the Royal Geographical Society, 

 who, in reply to my inquiry as to any ascents of the Uaupes 

 since my journey, sent me two volumes of the Bolletino delta 

 Societa Geographica Italiana (1887 and 1900), which, give, so 

 far as he can ascertain, all that is known of Count Stradelli's 



