The New Orleans bulletin. [volume] (New Orleans [La.]) 1874-1876, 1876-02-13
ARTIFICIAL PEARLS.

IL WH8 oUOub tu0 o0voUtcoot0 C0k4tu4y tAos ~
was tried with more or less success to initiate
real pearls, and the most successful means to
which recourse was had was with the aid OF
tho ''Oriental essence" or pearly white solu-
ton from the scales Of the bleak, called
guanine. In giving to this product the name
s.Oriental essence, it Was with the intention
of Keeping the substance secret. In AnJou,
although this industry chat is to say, the
bleak fishery to obtain the Oriental essence }
is little known, it is no less certain that the
fishermen of Ecouflans and Ponts-de-Ce
largely aid the manufacture of imitation
pearls and that they still use this name, or
that of bleak white. The scale OF the bleak
is fabricated by mucus which was TOR long
time considered albuminous, but it Is not
90. This essence is very abundant, and is
difficult to mix with water. 1t coagulates by
heat to thick white deposit, and becomes
black in time if . proper remedy be not ap-
Piled to prevent this deterioration, especially
during the time of intense heat, during which
period fishing is at its height in the Loire
and the Mayenne. If the scales Of the bleak
are examined under the microscope, the
smallest are found to be nearly round; and if
the surface of one of the larger ones is lightly
pressed, this "Oriental essence" under the
form of small pearly drop, issues from one
Of the canals and sticks to the fingers. In this
mucilage an infinite number of small. rudi-
mental, pearly scalea can be seen. The
largest scales are square, nearly rectangular,
four times as long as they are wide; each scale
has three colorless cylindrical veins. 1t is to
M. Joaquin that this invention is
due, all the more fortunate as it RENE
died the difficulties and bad effects Of
the pearls made Of quicksilver placed in y
glass bulb. In Anjou, in order to obtain this
sOriental essence" they only fish for the
bleak: however, the scales of the dace furnish
it also. The bleak (Leuciscus albunus) is the
only river fish which is not used for
food; it is q white fish, we'll known in the
running streams and on the fat,
sandy coasts of France, where the va or
is not deep; it is also found in the Seine,
Marne, Moselle, Escaut, ETC., never descend
ing into the Black Sea, being principally
found at the mouth q rivers. In Apjou they
spawn on the sand jim the months of May and
June. For its propagation in certain parts Of
France, artificial spavning places are made by
the aid of heaps Of sand where they multiply.
In Anjou, recourse i not had to any artificial
means; they breed Under the shelter Of the
fiat, sandy coast. thus avoiding becoming the
prey of other fishes.
the bleak by thousands as they travel in shoals
in the current, taking care not to let them
get entangled in the meshes, or wound them
selves or loose part of their large scales;
but, above all, nos-tp stain themselves with
The following is the process of extracting
the "Oriental essence" Men and children,
provided with blunt knives, take the fl sh one
after the other and scrape them over shallow
tub, containing little fresh water. Care is
taken not to scale the black or dorsal part, as
these scales are yellow, while the white scales
are very valuable. The whole is received on
a horsehair sieve. The first water, mixed
with q little blood, is thrown away. The
scales are then washed and pressed; the es-
sence settles at the bottom of the tub, and it
is then that we have very brilliant, blue
white, oily mass. Warm water must not be
used for the washing, as it would promote fer
mentation. It takes 10000 bieaks to furnish
two pounds of essense.
The fishermen put this guanine in tin boxes,
which they fill up with ammonia the box is
then closed and sent to Paris. Others pre- fer
to put it in large-mouthed bottles. II drop
Of the essence is taken up by straw and let
fall upon water, the guanine floats, giving
forth the most brilliant colors The intes-
tines Of the bleak are thrown away. They
are, however, covered with this mucus There
is here great negligence, and, in spite of all
the advice given on the subject, the fisher.
men lose large part of the produce. This
guanine is insoluble in water. in ammonia,
and in acetic acid, but combines with sui
phuric and other acids. We know that the
pancreas also furnishes this substance. There
is no doubt that they are wrong to neglect
that which covers the intestines. Although
The yield would be small for each fish, it is
none the less true that large quantities could
he an ohtainad Hen;ereS' (An0erS Jour-
nal Of Applied Sciences.