ve coating for bottles or "preparation" jars, is attacked by
the contained spirit in such a manner as to be useless as a preventive
of evaporation. Ordinary sealing wax, "bottle wax," beeswax, or
paraffin wax, being useless, we are driven back on a very old recipe
of the French naturalist M. Peron, who claimed for it advantages which
it certainly possesses.

No. 30.--"Lithocolle" for Sealing Bottles.

Common resin.

Yellow beeswax (or paraffin wax).

Red ochre (in powder).

Oil of turpentine (turps).

The proportions of this luting are determined by putting more or less
resin and red ochre, or turpentine and wax, as the "lithocolle" is to
be more or less brittle or elastic. Melt the wax in the resin, then
add the ochre in small quantities, and at each addition of this stir
the whole briskly round. When the mixture has boiled seven or eight
minutes, pour in the turpentine, stir it round, and set it near the
fire to keep it warm some little time. To ascertain the quality, and
if it requires more or less wax, put a little out on a cold plate, and
note its degree of tenacity.

It is rather dangerous to prepare, and is best managed over a gas jet
or stove, so arranged that the flame does not rise above the edge of
the iron pot containing the composition; if this is attended to, not
much danger can arise, especially if, in case of the composition
firing, the lid of the pot be immediately clapped on.

Apply with an old brush, or by repeatedly plunging the neck of the
bottle in the luting before the latter becomes cold. I have used an
application of glue with great success on corks over spirits, by
procuring the best glue, making it rather thin, and applying it whilst
hot in successive coats. It will not do, however, for non-alcoholic
solutions, nor for glass stoppers, from which it scales off when cold.

GENERAL REMARKS.

In all cases when "pickling" animals it must be remembered that the
first pickle, whether alcoholic or not, is essentially deteriorated by
the bloody mucus and water which exudes from the specimens, especially
if large and "flabby;" this, of course, reduces the strength of the
preservative medium. It is well, therefore, to have from three to four
different vessels, in which the objects shall be successively immersed
for several days, or even weeks, until, coming to the final
preparation jar, they shall not stain the liquid in which they are
ultimately to rest.

By using the various strengths of