Bradford reporter. [volume] (Towanda, Pa.) 1844-1884, 1865-10-19
CORAL ROCKS.

The coral rocks, which grow from the
bed of the ocean, were formerly thought to
be OF vegetable nature but subsequent
investigation has demonstrated that the
foundation of these immense masses is eff
fected by certain species of polypes. A
portion even of England is based on foun-
dation of coral, many of our transition
rocks containing an immense number OF
fossil corals and many islands between
the tropics appear to rest entirely on mass
es of coral rocks The order and regularl-
ty with which these vast accumulatIons OF
solid matter are constructed, by means
apparently 50 inadequate to the end, are
no less astonishing than the amazing num-
Der of such masses which are known to
exist
Thousands of islands in the Eastern
Ocean owe their origin entirely to this
source and particularly those in the In
dian Archipelago, and round New Holland,
are produced by various tribes of these an
imals !; especially by the cellepora, isis, ma
drepora, millepora, and tubipora. The ami
mails which form these corals work with
such rapidity, that enormous masses of
them appear where there were scarcely any
marks of such reefs before and the navi-
cation of the seas in which they abound is
rendered every day more difficult by the
continually increasing number of coral
reefs, which will become the basis of future
islands These reefs have fiat tops, and
rise so perpendicularly from the bed of the
sea, that the officers of vessels, within only
two ships length Of them, have found no
bottom at the depth Of $50 fathoms, or nine
hundred feet 1t is an interesting object
Of geological research to trace the progress
of these foundations, by the minute but
combined labors of millions of these marine
zoophites, which occupy the lowest rank in
the animal kingdom but which have been
instrumental in giving to the earth its pres
ent form. The following interesting ex
tract from Kotzebue's Voyages" " gives
the best description of the mode III which
the islands consisting of coral reefs, may
have been progressively formed:
"As soon as the ridge or reef has reach
ed such height that it remains almost dry
at low water, at the time of ebb, the poly
pes cease from building higher. Seashells,
fragments Of corals, sea hedgehog shells,
and their broken off prickles, are united by
the burning sun, through the medium of
the cementing calcareous sand, which has
arisen from the pulverizatiOn of the above
mentioned shells, into one whole or solid
stone which, strengthened by the contin-
ual throwing up of new materials gradual
" increases in thickness, till it becomes at
last so high, that is covered only during
some seasons of the year by high tides
The heat Of the sun so penetrates the mass
of stone, when it is dry, that it splits in
many places, and breaks off in fakes
These flakes, so separated, are raised one
upon another by the waves, at the time of
high water The always active surf throws
blocks of coral Frequently of tathom in
length, and three or four feet thick and
shells of marine animals, between and up
on the foundation stones after this the
calcareous sand lies undisturbed, and of
| fers to the seeds and trees of plants, cast
upon it by the waves, a soil, upon which
| they rapidly grow, to overshadOw its daz-
zling white surface Entire trunks of trees
which are carried from other countries and
islands, find here, at length, a resting place
after their long wanderings. With these
come some small animals, such as lizards
and insects, as the first inhabitants Even
before the trees form wood, the real sea
birds nestle here, strayed land birds take
refuge in the bushes, and at much later
period, when the work has been long since
been completed, man also appears builds
his hut on the fruitful SOIL formed by the
corruption of the leaves of the trees, and
calls himself the lord and proprietor of this
new creation"