GANATE OF POTASH (see chapter IV) is recommended at p. 49,
Science Gossip, 1879, by a French scientist, for "preserving delicate
organisms." "It is especially good in histological researches, as it
acts like osmic acid, burning up the protoplasm, bringing out the
minutiae, and showing the nuclei, outlines of cells, etc. It is used as
a saturated solution in distilled or very pure spring water; sea-water
also dissolves it. The concentrated solution, of a lovely violet
colour, kills small organisms at once, and then burns them. They are
left in it from thirty minutes to an hour, then withdrawn, and placed
in alcohol, after which they can be made transparent with essence of
terebinth and mounted in Canada balsam. Beautiful results are thus
obtained with echinoderms, zoophytes, worms and marine arthropoda. For
delicate researches, especially in the ciliated infusoria, it is
better than osmic acid, without its great cost, and is everywhere
easily obtained."--G. du Plessis.

GLYCERINE (see Chapter IV).--Glycerine will be found useful for
rubbing on the eyes or noses of animals to keep them moist and prevent
their drying up when modelling, as well as for many other purposes,
which will readily occur to the practical worker.

CORALS, etc, may be cleaned by first soaking in warm water, to remove
surface dust, etc, then allowing the tap to run on them for some hours,
and afterwards soaking them in a weak solution of chloride of lime for
a short time, until fairly bleached.

BIRDS may be roughly preserved from immediate decay by pouring down
their throats, or into their bodies by an incision under the wing,
crude creosote or carbolic acid. I remember once having a collection
of birds from India prepared in this way, which after a lapse of years
were successfully skinned and made up--"as well as could be expected."

Sometimes I have been written to by correspondents to say that they
had cured some mammals' skins by Formula No. 9, and that there was an
efflorescence about the mouth, or that mildew had appeared. My answer
has ever been:

Firstly, that possibly the specimen had been cased up too soon. At
least two months should elapse after stuffing before mammals should be
mounted in a case.

Secondly, that common alum had been used instead of burnt alum.

Thirdly, that an undue proportion of saltpetre had been mixed with the
alum.

Should mildew make its appearance, it would point to improper mounting
--i.e, not trimming o