The method which is here recommended originated with Dr. M. Buchner,
and consists in preparing a concentrated solution of alcoholic caustic
potash--one part caustic potash to three of 90 per cent. alcohol--and
then boiling one to two grammes of the suspected wax in a small flask
with the above solution. The liquid is poured into a glass cylinder to
prevent solidification of the contents, and it is then placed for
about one half hour in boiling water. With pure wax the solution
remains clear white; when ceresine and paraffine are present, they
will float on the surface of the alkali solution as an oily layer, and
on cooling they will appear lighter in color than the saponified mass,
and thus they may be quantitatively estimated. The author likewise
gives a superficial method for the determination of the purity of
beeswax. It depends on the formation of wax crystals when the fused
wax solidifies. These crystals form on the surface on cooling, and are
still visible after solidification when examining the surface from the
side. The test succeeds best when the liquid wax is poured into a
shallow tin mould After cooling another peculiar property of the wax
becomes apparent. While the beeswax fills a smaller volume, that is,
separates from the sides of the mould, the Japanese wax, without
separating from the sides, becomes covered with cracks on cooling
which have a depth corresponding to the thickness of the wax.--_Neuste
Erfindungen und Erfahrungen_, viii., p. 430.
* * * * *