palms and cactuses, lianes and trees.  Red stacks and skerries stood isolated and ready to fall at the end of the point, showing that the land has, even lately, extended far out to sea; and that Point Rouge, like Point Courbaril and Point Galba—­so named, one from some great Locust-tree, the other from some great Galba—­must have once stood there as landmarks.  Indeed all the points of the peninsula are but remnants of a far larger sheet of land, which has been slowly eaten up by the surges of the gulf; which has perhaps actually sunk bodily beneath them, even as the remnant, I suspect, is sinking now.  We scrambled twenty feet down to the beach, and lay down, tired, under a low cliff, feathered with richest vegetation.  The pebbles on which we sat were some of pitch, some of hard sandstone, but most of them of brick; pale, dark, yellow, lavender, spotted, clouded, and half a dozen more delicate hues; some coarse, some fine as Samian ware; the rocks themselves were composed of an almost glassy substance, strangely jumbled, even intercalated now and then with soft sand.  This, we were told, is a bit of the porcellanite formation of Trinidad, curious to geologists, which reappears at several points in Erin, Trois, and Cedros, in the extreme south-western horn of the island.

How was it formed, and when?  That it was formed by the action of fire, any child would agree who had ever seen a brick-kiln.  It is simply clay and sand baked, and often almost vitrified into porcelain-jasper.  The stratification is gone; the porcellanite has run together into irregular masses, or fallen into them by the burning away of strata beneath; and the cracks in it are often lined with bubbled slag.

But whence carne the fire?  We must be wary about calling in the Deus e machina of a volcano.  There is no volcanic rock in the neighbourhood, nor anywhere in the island; and the porcellanite, says Mr. Wall, ’is identically the same with the substances produced immediately above or below seams of coal, which have taken fire, and burnt for a length of time.’  There is lignite and other coaly matter enough in the rocks to have burnt like coal, if it had once been ignited; and the cause of ignition may be, as Mr. Wall suggests, the decomposition of pyrites, of which also there is enough around.  That the heat did not come from below, as volcanic heat would have done, is proved by the fact that the lignite beds underneath the porcellanite are unburnt.  We found asphalt under the porcellanite.  We found even one bit of red porcellanite with unburnt asphalt included in it.