circumstance from finding on its inland flank the last remains of three
small points of eruption. These points are composed of glossy scoriae,
cemented by crystalline calcareous spar, exactly like the great submarine
calcareous deposit, where the heated lava has rolled over it: their
demolished state can, I think, be explained only by the denuding action of
the waves of the sea. I was guided to the first orifice by observing a
sheet of lava, about two hundred yards square, with steepish sides,
superimposed on the basaltic plain with no adjoining hillock, whence it
could have been erupted; and the only trace of a crater which I was able to
discover, consisted of some inclined beds of scoriae at one of its corners.
At the distance of fifty yards from a second level-topped patch of lava,
but of much smaller size, I found an irregular circular group of masses of
cemented, scoriaceous breccia, about six feet in height, which doubtless
had once formed the point of eruption. The third orifice is now marked only
by an irregular circle of cemented scoriae, about four yards in diameter,
and rising in its highest point scarcely three feet above the level of the
plain, the surface of which, close all round, exhibits its usual
appearance: here we have a horizontal basal section of a volcanic spiracle,
which, together with all its ejected matter, has been almost totally
obliterated.

The stream of lava, which fills the narrow gorge eastward of the town of
Praya, judging from its course, seems, as before remarked, to have come
from Signal Post Hill, and to have flowed over the plain, after its
elevation (The sides of this gorge, where the upper basaltic stratum is
intersected, are almost perpendicular. The lava, which has since filled it
up, is attached to these sides, almost as firmly as a dike is to its walls.
In most cases, where a stream of lava has flowed down a valley, it is
bounded on each side by loose scoriaceous masses.): the same observation
applies to a stream (possibly part of the same one) capping the sea cliffs,