THE PACIFIC OCEAN. 269 
is excluded. It almost invariably happens that, in 
the line of reef, one or more openings occur, which, 
though sometimes narrow and intricate, so as scarcely 
to allow the passage of a native canoe, are not un- 
frequently of sufficient width and depth to permit 
the free ingress of large ships. This is a very re- 
markable instance of the Divine care over the little 
creatures which rear these solid structures; they 
appear to be endowed with an instinctive knowledge, 
that if the reef were carried uninterruptedly along 
from one point to another, so as completely to shut 
in the lagoon, the water within would soon become 
unfit to support their existence, and would ulti- 
mately be dried up. The advantage to man of these 
openings is very great; without them the islands 
might smile invitingly, but in vain; no access could 
be obtained to them by shipping, through the tre- 
mendous surf by which their shores are lashed; but’ 
by these entrances the lovely lagoons are converted 
into the most quiet, safe, and commodious havens 
imaginable, where ships may lie, and wood and 
water, and refregh their crews, in security, though 
the tempest howl without. It is a scarcely less 
beneficent provision that the position of the open- 
ings is in most cases indicated so as to be visible 
at a great distance. Had there been merely an 
opening in the coral rock, it could not have been 
detected from the sea, except by the diminution 
of the foaming surf just at that spot; a circumstance 
that could scarcely be visible, unless the observer 
were opposite the aperture. But, in general, there 
is on each side of the passage, a little islet, raised 
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