ld ultimately yield and be demolished by
such irresistible forces. Yet these low insignificant coral islets stand
and are victorious, for here another power, as antagonist to the former,
takes part in the contest. The organic forces separate the atoms of
carbonate of lime one by one from the foaming breakers, and unite them
into a symmetrical structure; myriads of architects are at work night
and day, month after month, and we see their soft and gelatinous bodies
through the agency of the vital laws conquering the great mechanical
power of the waves of an ocean, which neither the art of man, nor the
inanimate works of nature could successfully resist."[1118]

As the coral animals require to be continually immersed in salt water,
they cannot raise themselves by their own efforts, above the level of
the lowest tides. The manner in which the reefs are converted into
islands above the level of the sea is thus described by Chamisso, a
naturalist, who accompanied Kotzebue in his voyages:--"When the reef,"
says he, "is of such a height that it remains almost dry at low water
the corals leave off building. Above this line a continuous mass of
solid stone is seen composed of the shells of mollusks and echini, with
their broken-off prickles and fragments of coral, united by calcareous
sand, produced by the pulverization of shells. The heat of the sun often
penetrates the mass of stone when it is dry, so that it splits in many
places, and the force of the waves is thereby enabled to separate and
lift blocks of coral, frequently six feet long and three or four in
thickness, and throw them upon the reef, by which means the ridge
becomes at length so high that it is covered only during some seasons of
the year by the spring tides. After this the calcareous sand lies
undisturbed, and offers to the seeds of trees and plants cast upon it by
the waves a soil upon which they rapidly grow, to overshadow its
dazzling white surface. Entire trunks of trees, which are carried by the
rivers from other countries and islands, find here, at length, a
resting-place after their long wanderings: with these come some small
animals such as insects and lizards, as the first inhabitants. Even
before the trees form a wood, the sea-birds nestle here; stray
land-birds take refuge in the bushes; and, at a much later period, when
the work has been long since completed, man appears and builds his hut
on the fruitful soil."[1119]

In the above description the