46G 
CONNEXION OE VOLCASOS. 
Parime, stretching from west to east.* in the inteiior of 
the continent, and not in a direction parallel with the coast, 
between the mouths of the river Amazon and the Orinoco. 
But though we find no chain of mountains at the north- 
east extremity of Terra Firms, having the same direction 
as the archipelago of the smaller West India Islands, it 
does not therefore follow that the volcanic mountains ol 
the archipelago may not have belonged originally to the 
continent, and formed a part of the littoral chain ol C aracas 
and Cumana.t . , , 
In opposing the objections ol some celebrated naturalists, 
I am far from maintaining the ancient contiguity ol all 
the smaller West India Islands. I am rather inclined to 
consider thorn as islands heaved up by lire, aud ranged m 
that regular line, of which we find, striking examples in so 
many volcanic hills in Auvergne, in Mexico, and in leru. 
The geological constitution ol the. Archipelago .appeals, 
from the little we know respecting it, to be very similar to 
"that of the Azores and the Canary Islands. Primitive for- 
mations are nowhere seen above ground ; we find only what 
beloims unquestionably to volcanos: feldspar-lava, dole- 
rite, basalt, conglomerated scoriae tufa, and pumice-stone. 
Am ong the limestone formations we must distinguish those 
which are essentially subordinate to volcanic tufas J from 
* From Ore cataracts of Atures towards the Essequibo River. Xlus 
chain of Pacaraimo divides the waters cf the Carony from those ot the 
Rio Parime, or Rio de Aguas Blancas. 
+ Among many such examples which the structure of the globe 
displays, we shall mention only the inflexion at a right angle termed hy 
the Higher Alps towards the maritime Alps, in Europe; and the peloui- 
Tagh, which joins transversely the Mouz-Tagh atul the Himalaya, m Asia. 
Amid the prejudices which impede the progress of nuneralogical geo- 
graphy, we may reckon, 1st, the supposition of a perfect umtorm.ty of 
direction in the chains of mountains; 2nd, the hypothesis ot the conti- 
nuitv of all chains ; 3rd, the supposition that the highest summits detei - 
mine the direction of a central chain; 4th, the tuea that, m all places 
where great rivers take rise, we may suppose the existence of great taolc- 
lands. or very high mountains. 
+ \\’e have noticed some of the above, following Von Buell, at Lance- 
rote and at Fortaventura, in the system of the Canary Islands. Among 
the 'smaller islands of the West Indies, the following islets are entirely 
calcareous, according to M. Cones : Mariegalante, La Desiradc, the 
Grande Terre of Guadaloupe, and tho Grenadillas. According to the 
observations .of that naturalist, Cura?oa and Buenos Ayres present omy 
