186
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VOYAGE TO THE
CHAP. the persecution of their conquerors. To remain, was certain deatli and
Feb.
1S26.
ignominy; to fly, was to leave their fate to chance.
The temporary obstruction of the trade-wind in these seas, by the
westerly monsoons, has not been duly considered by those who represent
the difficulties as insurmountable. At the period of the year
corresponding w-ith our spring these gales commence, and blow with
great violence during the rainy season. As they arise very suddenly,
any canoes at sea must have difficulty in escaping them, and would, in
all probability, be driven so far, as never to be able to regain tlieir native
country, or be drifted to islands upon wliich tliey might be contented
to dwell, in preference to encountering farther risks.
The traces of inhabitants upon almost all the islands of tlie low
archipelago, many of which are at present uninhabited, show the frequency
with which these migrations have occurred, and how extensive
they have been: some of these isolated spots where remains have been
found, Pitcairn Island for instance, are 400 miles from any land whence
inhabitants were likely to be derived; and the circumstance of their
having abandoned the island is a fair presumption that the people
who landed there knew of other lands which there was a probability of
their reaching, and which certainly could not be the coast of America, at
least 2000 miles against the trade-wind.
I shall now- b rin g to g e th e r a few facts co nnected with th e formatio
n o f th e se islands, which it is h oped may be useful to those persons
who are in te re s ted ab o u t it, observing, in ex te n u atio n o f th e absence o f
more d e ta iled information, th a t o u r time d id n o t admit o f m ore th an
was actually essential to th e purposes o f a correct delineation o f them,
a n d th a t in general th e islands were so su rro u n d ed by breakers th a t it
was dangerous to approach them, in th e ship in particular, which alone
was calculated to obtain very d e ep soundings. 'I'o windward this
could n o t be done o f course, and to leeWard th e re was not u n frequently
a heavier swell se ttin g upon th e island th a n in o th e r p a rts o f it.
In speaking of the coral islands hereafter, my observations will be
applied to the thirty-two islands already stated to have fallen under our
examination. The largest of them was thirty miles in diameter, and
the smallest less than a mile: they were of various shapes ; w-ere all
PACIFIC AND BEERING’S STRAIT. 187
formed of living coral, except Henderson’s Island, which was partly sur- C H A P
rounded by it ; and they all appeared to be increasing their dimensions
by the active operations of the lithophytes, w-hich appeared to be gradually
Feb.
1826.
extending and bringing the immersed parts of their structure to
the surface.
Twenty-nine of tlie number had lagoons in their centres, which is
a proportion sufficiently large, when coupled with information supplied
from other parts of the globe where such formations abound,
to render it almost certain that the remainder also had them in the
early period of their formation, and that such is the peculiar structure
of the coral islands. And, indeed, these exceptions can scarcely be considered
objections, as tw-o of tliem—Tlirum Cap, which is only seventeen
hundred yards long by twelve hundred broad ; and Queen Charlotte’s
Island, which is not more than three quarters of a mile wide in its
broadest part, and less than half a mile in other places—are so circumstanced,
that, had their lagoons existed, they would have been filled in
the course of time with the masses of coral and other substances w-hich
the sea heaps upon sucli formations as they rise above the surface ; they
have, besides, long been wooded and inhabited, though deserted at the
present moment, botli of which would tend to efface the remains of a
lagoon of such small dimensions. The sea, how-ever, prevented our
boats from landing upon either of these islands to ascertain the fact
of tlie early e.xistence of lagoons. The other exception, Henderson’s
Island, though of coral formation, appears to have been raised to its
present heiglit above the sea by a subterraneous convulsion, and has its
centre so incnmbered and overgrown witli bushes that we could not
determine wliether it ever had a lagoon.
In the above-mentioned twenty-nine islands the strips of dry coral
enclosing the lagoons, divested of any loose sandy materials lieaped
upon tliem, are rarely elevated more than tw-o feet above the level of
the sea ; and w-ere it not for tlie abrupt descent of tlie external margin,
wliicli causes the sea to break upon it, these strips would be wholly
inundated ; this height of two feet is continued over a small portion only
of the width of the island, which slopes on both sides, by an almost
imperceptible inclination to the first ledge, where, as I said before, its
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