1852.] DISAPPOINTMENTS. 249 



the height of the river above the sea-level, at the point I 

 reached. Nothing, however, can accurately determine this fact, 

 but a series of barometer or " boiling-point " observations ; and 

 to determine this height above the next great fall, and ascertain 

 the true course and sources of this little-known but interesting 

 and important river, would be an object worth the danger and 

 expense of the voyage. 



There is said to be a week's smooth water above this place, 

 to the Jurupari caxoeira, which is higher than any below it ; 

 and above this no other fall has been found, though traders 

 have been ten or fifteen days up. They say the river still keeps 

 as wide or wider than below, that the water is as " white," or 

 muddy, as that of the Solimoes, that many trees, birds, and 

 fish peculiar to the Solimoes are there found, that the Indians 

 have Spanish knives, ponchos, and coins, and relate that, 

 higher up, there are extensive " campos," with cattle, and men 

 on horseback. All these interesting particulars seem to show 

 that the river has its sources in the great plains which extend 

 to the base of the Andes, somewhere near where the sources of 

 the Guaviare are placed in most maps; but the latter river, 

 from all the information I can obtain, is much smaller, and 

 has a much shorter course. Having only a pocket surveying 

 sextant, without any means of viewing two objects much 

 differing in brilliancy, I endeavoured to obtain the latitude as 

 accurately as I could, first by means of the zenith-distance at 

 noon, obtained by a plumb-line and image of the sun, formed 

 by a lens of about fifteen inches focus ; and afterwards, by the 

 meridian altitude of a star, obtained on a calm night, by 

 reflection in a cuya of water. I took much care to ensure an 

 accurate result, and have every reason to believe that the mean 

 of the two observations will not be more than two or three 

 minutes from the truth. 



My expectations of finding rare and handsome birds here 

 were quite disappointed. My hunter and Senhor Nicolau 

 killed a few umbrella-birds of the Rio Negro species ; but of 

 the white bird such contradictory statements were given, 

 many knowing nothing whatever about it, others saying that it 

 was sometimes, but very rarely seen, that I am inclined to 

 think it is a mere white variety, such as occurs at times with 

 our blackbirds and starlings at home, and as are sometimes 

 found among the curassow-birds and agoutis. Another bird, 



