By A. Peltz.

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.