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Typo: A Monthly Newspaper and Literary Review, Volume 1
Trade Wrinkles
Trade Wrinkles.
To Separate the Leaves of Charred Books, Deeds, &c., a French official has devised the following means: Cut off the back of the charred book so as to render the leaves absolutely independent of each other, then soak them, and dry them rapidly by a current of hot air. The leaves will then separate, but must, of course, be handled with extreme care.
Gilding Glass and Ivory.—The Glashatte states that to apply decoration upon ivory or glass, the design must be painted over with a fine camel-hair brush, on which is nitro-muriate of gold. The glass or ivory is then held over the mouth of a bottle in which hydrogen gas has been generated by the action of diluted sulphuric acid upon zinc. The hydrogen will reduce the chloride of gold on the painted surfaces into metallic gold, and the thin gold film thus precipitated will, in a short time, assume considerable brightness.—Another Method for the same purpose is specially applicable to glass. Gold-dust is prepared by placing leaf-gold with a little honey or thick india-rubber mucilage in an earthen vessel, and then rubbing the mixture well until the gold has been changed into dust, when the honey is removed by repeated rinsings with warm water. The gold-dust is then mixed with a strong solution of borax, and the pattern is coated with the composition. When dry, the glass is placed in an oven, and considerably heated. By this means the borax and cement are sufficiently vitrified for the gold to adhere firmly to the glass.
(From the Scientific American.)
Ink for Hand Stamps.—The following recipe is for an ink that will not injure the rubber:—Mix and dissolve two to four drachms aniline color, fifteen ounces alcohol, fifteen ounces glycerine. The solution is poured on the cushion and rubbed in with a brush.
(From the British and Colonial Printer and Stationer.)
A Crystalline Coating for Paper may, it is said, be obtained by mixing a very concentrated cold solution of salt with dextrine, and laying the thinnest coating of the fluid on the surface to be covered by means of a broad soft brush. After drying, the surface has a beautiful bright mother-of-pearl coating, which, in consequence of the dextrine, adheres closely to paper or wood. The coating may be made adhesive to glass by doing it over with an alcoholic shellac solution. Sulphate of magnesia, acetate of soda, and sulphate of tin, are among the salts which produce the most attractive crystalline coatings. Paper must first be sized, otherwise it will absorb the liquid and prevent the formation of crystals.
(From the Printing Times.)
Belts and Drums.—Steel is, strength for strength, considerably lighter than wrought iron, and resists torsion better. A curious fact is, that a strap or belt running on a wrought drum has at the least one-third more « bite, » or, in other words, a three-inch strap with a wrought drum is equal to a four-inch belt on cast iron. The cast-iron drum will weigh at least twice as much as the smaller and slighter-made wrought-iron one. Another consideration is, that in case of fire cast drums fly to pieces, whilst steel shafting and wrought drums can be easily repaired and used again. Moreover, as three-fourths only of the width of belt is required to replace them, a saving of fully 25 per cent. is effected. In speaking of belts, it is not generally known that the outside of the leather should run next the pulley—not the fleshy side—the « bite » is better; the strap can be run tighter, and will wear longer.