460 



from their basin, and mingles it's waters with 

 those of the Baltic. 



In South America an immense plain contains 

 the basin of the Amazon, and a portion of the 

 basin of the Oroonoko ; but in Germany, be- 

 tween Melle and Osnabrueck, we have the 

 rare example of a very narrow valley containing 

 two basins of little rivers independant of each 

 other. The Else and the Haase begin to rise in 

 a near and parallel course from south to north ; 

 but on entering the plain, they diverge to the 

 east and west, and join two hydraulic systems 

 entirely different, those of the Werra and of the 

 Ems. 



I come now to the third peculiarity to be 

 observed in the course of the Upper Oroonoko, 

 that bifurcation, the existence of which was held 

 in doubt at the moment of my departure for 

 America. This bifurcation {divergium amnis), 

 according to the astronomical observations* 



* These observations were of some importance, because no 

 other has ever been made at a more central point of South 

 America, north of the equator. In the night of the 22d of 

 May, I observed the passage over the meridian of « of the 

 Cross, and # of the Centaur. The first gives, for the latitude 

 of the mission of Esmeralda, 3° 11' 8" j the second, 3° 10' 52". 

 Six horary angles of the Sun, none of which differed more 

 than 1'2'* from the mean, fix, according to the chronometer, 

 the longitude of the mission at 68° 23' 19". As the rate of 

 the timekeeper could be verified by twice passing the 



