MISTINESS OF THE ATMOSPHERE. 
403 
my part, was afraid lest I should again find the fogs of the 
Bio .Negro in the valley of the Cassiqniare. Wo one in 
these missions for half a century past had doubted the 
existence of communication between two great systems of 
rivers; the important point of our voyage was confined there- 
fore to fixing by astronomical observations the course of the 
Cassiqniare, and particularly the point of its entrance into 
the Bio Negro, and that of the bifurcation of the Orinoco. 
Without a sight of the sun and the stars this object would 
be frustrated, and we shoidd have exposed ourselves in vain 
to long and painful privations. Our fellow travellers would 
have returned by the shortest way, that of the Phnichin and 
the small rivers; but M. Bonpland preferred, like me, per- 
sisting in the plan of the voyage, which we had traced for 
ourselves in passing the Great Cataracts. We had already 
travelled one hundred and eighty leagues in a boat from San 
Fernando de Apure to San Carlos, on the Bio Apure, the 
Orinoco, the Atabapo, the Temi, the Tuami.ni, and the Bio 
Negro. Iu again entering the Oriuoeo by the Cassiquiare 
we had to navigate three hundred and twenty leagues, from 
San Carlos to Angostura. By this way we had to struggle 
against the currents diming ten days; the rest was to be 
performed by going down the stream of the Orinoco. It 
would have been blamable to have suffered ourselves to be 
discouraged by the fear of a cloudy sky, and by the mos- 
quitos of the Cassiquiare. Our Indian pilot, who had been 
recently at Mandavaea, promised us the sun, and “those 
great stars that eat the clouds,” as soon as we should have 
left the black waters of the Guaviarc. We therefore carried 
out our first project of returning to San Fernando de Ata- 
bapo by the Cassiquiare ; and, fortunately for our researches, 
the prediction of the Indian was verified. The white waters 
brought us by degrees a more serene sky, stars, mosquitos, 
and crocodiles. 
We passed between the islands of Zaruma and Mini, or 
Mibita, covered with thick vegetation; and, after having 
ascended the rapids of the Piedra de TJimmane, we entered 
the Bio Cassiquiare at the distance of eight miles from the 
small fort of San Carlos. The Piedra, or granitic rock 
which forms the little cataract, attracted our attention on 
account of the numerous veins of quartz by which it is 
2 d 2 
