860 



metals; and some grains of gold have been 

 found in the mountains of Parima, near the mis- 

 sion of Encaramada. How can we infer the 

 absolute sterility of the primitive rocks of Guyana 

 from testimony merely negative, from the cir- 

 cumstance, that during a journey of three 

 months we saw no auriferous vein appearing 

 above the soil ? 



In order to bring together whatever may en- 

 lighten the government of this country on a 

 subject so long disputed, I shall enter into a few 

 more general geological considerations. The 

 mountains of Brazil, notwithstanding the nu- 

 merous traces of imbedded ore which they dis- 

 play between Saint Paul and Villarica, have 

 furnished hitherto only stream-works of gold. 

 More than six sevenths of the seventy-eight 

 thousand marks* of this metal, which at the 

 beginning of the 19th century America has an- 

 nually furnished to the commerce of Europe, 

 have come, not from the lofty Cordillera of the 

 Andes, but from the alluvial lands on the east 

 and west of the Cordilleras. These lands are 

 raised but little above the level of the sea, like 

 those of Sonora in Mexico, and of Choco and 

 Barbacoas in New Grenada; or they stretch 

 along in tablelands, as in the interior of Bra- 



Buria, los Tequcs, and los Marietus. See above, Vol. iii, 

 p. 525, 529. 



* Value 65,878,000 franks. 



