e was reduced to about 700 yards. It was composed entirely
of incoherent ejected matter, scoriae, pumice, and lapilli, forming
regular strata, some of which are described as having been parallel to
the steep inward slope of the crater, while the rest were inclined
outwards, like those of Vesuvius.[598] When the arrangement of the
ejected materials has been determined by their falling continually on
two steep slopes, that of the external cone and that of the crater,
which is always a hollow inverted cone, a transverse section would
probably resemble that given in the annexed figure (61). But when I
visited Vesuvius, in 1828, I saw no beds of scoriae inclined towards the
axis of the cone. (See fig. 45, p. 381.) Such may have once existed; but
the explosions or subsidences, or whatever causes produced the great
crater of 1822, had possibly destroyed them.

[Illustration: Fig. 61.]

Few of the pieces of stone thrown out from Graham Island exceeded a foot
in diameter. Some fragments of dolomitic limestone were intermixed; but
these were the only non-volcanic substances. During the month of August,
there occurred on the S. W. side of the new island a violent ebullition
and agitation of the sea, accompanied by the constant ascension of a
column of dense white steam, indicating the existence of a second vent
at no great depth from the surface. Towards the close of October, no
vestige of the crater remained, and the island was nearly levelled with
the surface of the ocean, with the exception, at one point, of a small
monticule of sand and scoriae. It was reported that, at the commencement
of the year following (1832), there was a depth of 150 feet where the
island had been: but this account was quite erroneous; for in the early
part of that year Captain Swinburne found a shoal and discolored water
there, and towards the end of 1833 a dangerous reef existed of an oval
figure, about three-fifths of a mile in extent. In the centre was a
black rock, of the diameter of about twenty-six fathoms, from nine to
eleven feet under water; and round this rock are banks of black volcanic
stones and loose sand. At the distance of sixty fathoms from this
central mass, the depth increased rapidly. There was also a second shoal
at the distance of 450 feet S. W. of the great reef, with fifteen feet
water over it, also composed of rock, surrounded by deep sea. We can
scarcely doubt that the rock in the middle of the larger reef is solid
lava, whic