Oil of Cloves to Preserve Paste.—The Superior Printer has the following recipe for a good paste, which will keep for months in a stoppered bottle:—Dissolve a piece of alum the size of a walnut in a pint of boiling water, to which two spoonfuls of flour, made smooth in a little cold water, and a few drops of oil of cloves have been added, the mixture being then boiled.

Liquefiable Sealing-wax.—Heat two parts Venice turpentine, and dissolve therein four parts white shellac; remove the heat, allow to cool somewhat, and add ten parts 96 per cent. alcohol. Rub five parts cinnabar into a paste with alcohol, and add this to the mixture, stirring constantly during the addition. The whole is put into convenient bottles, and whenever it is desired to use the wax the preparation can be made perfeetly fluid by immersing the bottles in warm water and shaking.

Washable Paper.—Writing- and drawing-paper are first coated thinly with a mixture of glue or some other suitable adhesive substance, with zinc, white chalk, barytes, &c., and the color for producing the desired tint. They are then coated with silicate of soda, to which a small quantity of magnesia has been added, and dried at a temperature of 77° Fahr. during ten days or so. Paper thus treated is said to possess the property of preserving writing or drawing in lead pencil, chalk, or indian ink, unaltered after being washed.

Preserving Printers' Inks.—In the case of inks kept in tin cans and used only occasionally, the Bulletin de l'Imprimerie advises that every time ink is taken from the can the surface be made perfectly smooth again, and the particles adhering to the tin be carefully removed, so as to diminish those parts liable to dry up. The ink is then covered with a sheet of parchment previously soaked in oil and well dried on both sides, care being taken that the ink is completely covered by the parchment. The can is then to be hermetically closed, wrapped in paper, and the ink can thus be preserved in good condition for a very long time.

Transferring Engravings.—The following method is described in Booklore:—The engraving is first exposed for ten seconds to the vapor of iodine. The paper on which the impression is to be reproduced has previously been dipped in a weak solution of starch, and, when dry, in a similar solution of oil of vitriol. When again dry, the prepared paper is placed on the engraving and put for a few minutes under a press, when all the fineness and delicacy of the print will be found to have been faithfully transferred. A little alcohol and water to sharpen the lines, and a few strokes of a pen to heighten the effect, and it would take a very expert critic to discover that it was not an original. This process applies only to line engravings. With ordinary typographic or lithographic ink, it would not succeed.