SUPPOSED MINERAL RICHES. 
341 
The astronomical observations made in the night of the 
25th of April did not give me the latitude with satisfactory 
precision. The latitude of the mission of San Fernando 
appeared to me to be 4° 2 ' 48". In Father Caulin’s map, 
founded on the observations of Solano made in 1756, it is 
4° 1'. This agreement proves the justness of a result which, 
however, I could only deduce from altitudes considerably 
distant from the meridian. A good observation of the stars 
at Guapasoso gave me 4° 2' for San Fernando de Atabapo. 
I was able to fix the longitude with much more precision 
in my way to the Bio Negro, and in returning from that 
river. It is 70° 30' 46" (or 4° 0' west of the meridian of 
Cumana). 
On the 26th of April we advanced only two or three 
leagues, and passed tho night on a rock near the Indian 
plantations or conucos of Guapasoso. The river losing itself 
by its inundations in the forests, and its real banks being 
Unseen, the traveller can venture to land only where a rock 
°r a small table-land rises above the water. The granite 
of those countries, owing to the position of the thin 
bin lime of black mica, sometimes resembles graphic granite ; 
but most frequently (and this determines the age of its for- 
•nation) it passes into a real gneiss. Its beds, very regularly 
stratified, run from south-west to north-east, as in the Cor- 
dillera on the shore of Caracas. The dip of the granite- 
gneiss is 70° north-west. It is traversed by an infinite 
•'limber of veins of quartz, which are singularly transparent, 
a nd three or four, and sometimes fifteen inches thick. I 
found no cavity (druse), no crystallized substance, not even 
r ock-crystal ; and no trace of pyrites, or any other metallic 
substance. I enter into these particulars on accoimt of the 
chimerical ideas that have been spread ever since the six- 
teenth century, after the voyages of Berreo and Baleigh,* 
°u the immense riches of the great and fine empire of 
'"‘-liana.” 
The river Atabapo presents throughout a peculiar aspect ; 
you see nothing of its real banks formed by flat lands eight 
* Raleigh’s work bears the high sounding title of ‘ 1 The Discovery of 
e large, rich, and beautiful Empire of Guiana.” {Land. 1596.) See 
Raleghi admiranda Descriptio Regni Guiante, auri abundant isbitoi 
'“ondius, Noribergae , 1599.) 
