Year: 1868

the living animal within esied, became
foundation for the homes of their sue
cessors. The polypi increase by bud
ding, the young creatures springlng
from the sides of the older animals, aud
there remaining fixed to grow and hard
en-. Although the single animals are
exceedingly minute, they increase 10
such immense numbers that they soon
gil large space. and numerous islands
have been formed by the slow and con-
slant upward growth of the coral until
it has reached the surface. Then the
constant action of the waves breaks OH
large portions of the mass from one
place to pile it upon another, and brings
drift wood to be detained by the obsta-
Gle and make a foundation for the solid
earth which finally accumulates. Asit
is impossible for the coral animals to
exist in very deep water. it was at first
difficult to account for their rearing
islands from the bottom Of the ocean.
The first supposition was, that they
built around the craters of extinct vol
canoes but the latest theory advocated
by Mr.. Darwin, attributes the factto the
gradual subsistence of the bed OF the
ocean in certain localities According
to this supposition, the corals must be-
gin their structure at time when the
ground upon which they build is sufh
GENTLY near the su. face to suit the ne
cessitics of their existence. Gradually
the slow growth of the coral keeping
pace with the equally slow alteration in
the bed of the ocean, the dead portions
of the mass sink, leaving the coral al
ways in favorable condition. When
the foundation becomes stationary, the
little creatures finally attain the surface
and cease their labors. The coral fish
cries are situated chiefly in the Medi-
terranean, where the red coral, which
is considered the most valuable, grows
in great banks. An engine, as it is
called. composed oftwo bars of wood and
network of lines, is let down over a
coral bank from the side of vessel,
and dragged along the bottom of the sea
until it catches in the rocks upon which
the coral grows. 1t is then raised by a
violent exertion on the part Of the crew
tearing up blocks of stone together with
the coral, which is collected and cleansed
before it is handed over to the jewel
Ter. Pearls are the third great pro-
duct of the ocean for which regular fish
cries have been established, the most
important being those in the Bay O
Bengal, Ceylon, and other parts of thu
Indian ocean. Here the pearl oyster il
procured by divers, who sink to the
bottom with the aid of f.large stones, ant
remain there for about 80 seconds gath
ering all the shells within reach. Th'
work is exceedingly severe, and the
men are frequently devoured by sharks
The search for pearls always ends a
noon, when a gun is fired, and all tn
boats return to the shore, in order tina
the load may be examined and care'
for by daylight. The shell. fish are pile'
together, and the heap is left for abou
ten days, by witch time the remain
become entirely decomposed. he shell
are then easily opened, the round pearls
which are found in the body of the oys
ter, are collected, and the valves of th'
oysters, which furnish nacre or moth
er-of.peal are cleansed aud sold by th
c,sk. The pearls are sifted to separat
the different sizes; the smaller ones ar
sold by weight and the others singly
according to their, value. The nacr
and the pearl are formed of essential
the same material, but the nacre is de
posted over the whole shell in layers
while the pearl is the result of an effor
on the part of the oyster to free itsel
f. ON the irritation of some foreign sub
stance which has penetrated within it
valves. AS the animal is incapable O
ejecting any intruder, such as an un
welcome grain of sand, itrenders it les
obnoxious by depositing around it tn
smooth and lustrous substance whicl
is so eagerly sought for by man. Th
Chinese are so well acquainted with thi
fact, that they force the oyster to form
pearls, by thrusting small figures of ii


between the valves, and then returnin
i the creature to the water, whence it
fshed up in the course of o few year,
and pearl is extracted retaining tn
shape Of the tin. There is but one kin
of oyster which possesses the power
producing pearls to any considerable el
tent, although they can occasionally b
found in other species of oysters, an
even In mussels.