nd the day after crossed over to Ondor, the chief
village of Goram.
Around this island extends, with few interruptions, an encircling coral
reef about a quarter of a mile from the shore, visible as a stripe of
pale green water, but only at very lowest ebb-tides showing any rock
above the surface. There are several deep entrances through this reef,
and inside it there is hood anchorage in all weathers. The land rises
gradually to a moderate height, and numerous small streams descend on
all sides. The mere existence of these streams would prove that the
island was not entirely coralline, as in that case all the water would
sink through the porous rock as it does at Manowolko and Matabello; but
we have more positive proof in the pebbles and stones of their beds,
which exhibit a variety of stratified crystalline rocks. About a hundred
yards from the beach rises a wall of coral rock, ten or twenty feet
high, above which is an undulating surface of rugged coral, which slopes
downward towards the interior, and then after a slight ascent is bounded
by a second wall of coral. Similar walls occur higher up, and coral is
found on the highest part of the island.
This peculiar structure teaches us that before the coral was formed land
existed in this spot; that this land sunk gradually beneath the waters,
but with intervals of rest, during which encircling reef's were formed
around it at different elevations; that it then rose to above its
present elevation, and is now again sinking. We infer this, because
encircling reefs are a proof of subsidence; and if the island were again
elevated about a hundred feet, what is now the reef and the shallow sea
within it would form a wall of coral rock, and an undulating coralline
plain, exactly similar to those that still exist at various altitudes up
to the summit of the island. We learn also that these changes have taken
place at a comparatively recent epoch, for the surface of the coral
has scarcely suffered from the action of the weather, and hundreds of
sea-shells, exactly resembling those still found upon the beach, and
many of them retaining their gloss and even their colour, are scattered
over the surface of the island to near its summit.
Whether the Goram group formed originally part of New Guinea or of Ceram
it is scarcely possible to determine, and its productions will throw
little light upon the question, if, as I suppose, the islands have been
entirely submerged within the epo
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