I Am Rather Inclined To Consider Them As Islands Heaved Up By Fire, And Ranged In That Regular Line, Of Which We Find Striking Examples In So Many Volcanic Hills In Auvergne, In Mexico, And In Peru.

The geological constitution of the Archipelago appears, from the little we know respecting it, to be very similar to that of the Azores and the Canary Islands.

Primitive formations are nowhere seen above ground; we find only what belongs unquestionably to volcanoes: feldspar-lava, dolerite, basalt, conglomerated scoriae, tufa, and pumice-stone. Among the limestone formations we must distinguish those which are essentially subordinate to volcanic tufas* from those which appear to be the work of madrepores and other zoophytes. (* We have noticed some of the above, following Von Buch, at Lancerote, 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. Cortes: Mariegalante, La Desirade, the Grande Terre of Guadaloupe, and the Grenadillas. According to the observations of that naturalist, Curacoa and Buenos Ayres present only calcareous formations. M. Cortes divides the West India Islands into, 1st, those containing at once primitive, secondary, and volcanic formations, like the greater islands; 2nd, those entirely calcareous, (or at least so considered) as Mariegalante and Curacoa; 3rd, those at once volcanic and calcareous, as Antigua, St. Bartholomew, St. Martin, and St. Thomas; 4th, those which have volcanic rocks only, as St. Vincent, St. Lucia, and St. Eustache.) The latter, according to M. Moreau de Jonnes, seem to lie on shoals of a volcanic nature.

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