arful escape, that
they caught the eye more like a flash of momentary light, than living,
moving forms. We flushed in the course of the day a white bird, or at
least nearly so, with a black ring round the neck, and a bill crooked
like the ibis, which bird indeed, except in colour, it more resembles
than any I have ever seen.*

(*Footnote. Since ascertained to be an Ibis--the Threskiornis
strictipennis.)

Among the trees seen in the course of this ramble, I had almost forgotten
to mention one which struck me more than any other from its resemblance
to a kind of cotton tree, used by the natives of the South Sea islands in
building their canoes.

February 7.

The day following we secured several boat-loads of rainwater, deposited
in the holes of the rocks, near our temporary observatory, and were the
better pleased with our success, as our well-digging had proved
unsuccessful.

GEOLOGY OF THE CLIFFS.

There was something particularly striking in the geological formation of
the cliffs that form the western side of this bay: and which rise from 70
to 90 feet in height, their bases apparently resting amid huge and
irregular masses of the same white sandstone as that which forms the
cliffs themselves, and from which this massive debris, strewn in all
conceivable irregularity and confusion around, appears to have been
violently separated by some great internal convulsion.

Some of these great masses, both of the living cliff and ruined blocks
beneath, are strangely pierced with a vein or tube of vitreous matter,
not less in some instances than 18 inches in diameter. In every place the
spot at which this tube entered the rock was indicated by a considerable
extent of glazed or smelted surface; but I am not sufficiently versed in
the science of geology to offer any specific theory to account for the
appearances I have described: the cliffs were rent and cracked in a
thousand different ways, and taking into consideration their strange and
wrecked appearance, together with the fact that lightning is known to
vitrify sand, may we not thus get a clue to the real agency by which
these results have been produced?*

(*Footnote. Since this was written, I have consulted my friend, Mr.
Darwin, who has kindly examined a specimen I brought away. He pronounces
it "a superficial highly ferrugineous sandstone, with concretionary veins
and aggregations." The reader should, however, consult Mr. Darwin's work
on the Geology of Volcanic