166 



heat of the atmosphere at Maypures. I found 

 the dip of the magnetic needle at Maypures 

 31*1° (centesimal division), consequently 1 '15° 

 less than the dip at the village of Atures, which 

 is 25' of latitude farther north. I do not find in 

 my registers the original observation of the 

 intensity of the magnetic force ; it is merely 

 said, that I had determined it in the open air, 

 near the church, and that it differed little from 

 that of Atures. 



April the 21st. Having spent two days and 

 half in the little village of Maypures, on the 

 banks of the Great Upper Cataract, we em- 

 barked at two in the afternoon in the same 

 canoe, which the missionary of Carichana had 

 parted with to us; and which was much damaged 

 by the shoals it had struck against, and the care- 

 lessness of the Indians. Still greater dangers 

 awaited it. It was to be dragged over land, 

 across an isthmus of thirty-six thousand feet ; 

 from the Rio Tuamini to the Rio Negro, to go 

 up by the Cassiquiare to the Oroonoko, and to 

 repass the two raudales. We examined the 

 bottom and sides of the canoe and judged it to 

 be capable of sustaining this long journey. 



When the traveller has passed the Great Cata- 

 racts, he feels as if he were in a new world ; 

 and had overstepped the barriers, which nature 

 seems to have raised between the civilized coun- 

 tries of the coast, and the savage and unknown 



