Paper and Printing Recipes Part 3

A CEMENT THAT WILL RESIST THE DAMP.

A cement that will resist the damp, but will not adhere if the surface is greasy, is made by boiling together 2 parts sh.e.l.lac, 1 part borax, and 16 parts water.

TO MAKE GLUE WATERPROOF.

The best substance is bichromate of potash. Add about one part of it, first dissolved in water, to every thirty or forty parts of glue; but you must keep the mixture in the dark, as light makes it insoluble. When you have glued your substances together, expose the joint to the light, and every part of the glue thus exposed will become insoluble, and therefore waterproof. If the substances glued together are translucent like paper, all will become waterproof; if opaque like wood, only the exposed edges will become so, but they also protect the interior--not exposed parts--against the penetration of moisture.

TWO GLUE RECIPES.

A glue ready for use is made by adding to any quant.i.ty of glue, common whisky, instead of water. Put both together in a bottle, cork it tight and set it for three or four days, when it will be fit for use without the application of heat. Glue thus prepared will keep for years, and is at all times fit for use, except in very cold weather, when it should be set in warm water before using. To obviate the difficulty of the stopper getting tight by the glue drying in the mouth of the vessel, use a tin vessel with the cover fitting tight on the outside to prevent the escape of the spirit by evaporization. A strong solution of isingla.s.s made in the same manner is an excellent cement for leather.

A valuable glue is made by an admixture with common glue of one part of acid chromate of lime in solution to five parts of gelatine. The glue made in this manner, after exposure, is insoluble in water, and can be used for mending gla.s.s objects likely to be exposed to hot water. It can also be made available for waterproofing articles such as sails or awnings, but for flexible fabrics it is not suitable. A few immersions will be found sufficient to render the article impervious to wet. It is necessary that fractured articles should be exposed to the light after being mended, and then warm water will have no effect on them, the chromate of lime being better than the more generally used bichromate of potash.

POSTAGE STAMP MUCILAGE.

Postage stamp mucilage can be made by dissolving an ounce of dextrine in five ounces of hot water, and adding one ounce of acetic acid and one ounce of alcohol. The dextrine should be dissolved in water in a glue pot, or some similar vessel, which will prevent burning. The quant.i.ties in this recipe may be varied by taking any required weights in the proportions mentioned. Dr. Phin says that dextrine mixed with water makes a good label mucilage if a drop or two of glycerine be added to it. Too much glycerine will prevent the mucilage drying; with too little it will be likely to crack.

HOW TO KEEP MUCILAGE FRESH.

To keep mucilage fresh, and prevent the formation of mould, drop into the bottle a few crystals of thymol, which is a strong and harmless antiseptic.

MUCILAGE IN A SOLID FORM WHICH WILL DISSOLVE IN WATER.

Mucilage in a convenient solid form, and which will readily dissolve in water, for fastening paper, prints, etc., may be made as follows:--Boil one pound of the best white glue, and strain very clear; boil also four ounces of isingla.s.s, and mix the two together; place them in a water bath--a glue pot will do--with one-half pound of white sugar, and evaporate till the liquid is quite thick, when it is to be poured into molds, dried, and cut into pieces of convenient size.

MUCILAGE FOR PASTEBOARD.

Persons are often at a loss for a very strong mucilage having sufficient power of tenacity to fasten sheets of pasteboard together. The following cement is recommended by a scientific authority. It has the additional advantage of being waterproof. Melt together equal parts of pitch and gutta-percha. To nine parts of this add three parts of boiled oil, and one-fifth part of litharge. Continue the heat with stirring until a thorough union of the ingredients is effected. Apply the mixture hot or somewhat cooled, and thinned with a small quant.i.ty of benzole or turpentine oil.

A PORTABLE INK.

The aniline colors, which possess great tinctorial powers, can be conveniently used in the preparation of a portable ink. Saturate white tissue paper with an aniline violet, or with aniline black, by dipping the sheets into a saturated alcoholic solution of these colors; then dry and pack them in suitable parcels, and you will have a portable ink, either violet or black.

INDELIBLE INDIA INK.

Draughtsmen are aware that lines drawn on paper with good India ink well prepared cannot be washed out by mere sponging or washing. Now, however, it is proposed to take advantage of the fact that glue or gelatine, when mixed with bichromate of pota.s.sa, and exposed to the light, becomes insoluble, and thus renders India ink, which always contains a little gelatine, indelible. Reisenbichler, the discoverer, calls this kind of ink "Harttusche," or "hard India ink." It is made by adding to the common India ink of commerce about one per cent, in a very fine powder, of bichromate of potash. This must be mixed with the ink in a dry state; otherwise, it is said, the ink could not be easily ground in water. Those who cannot provide themselves with ink prepared as above in a cake, can use a dilute solution of bichromate of potash in rubbing up the ink. It answers the same purpose, though the ink should be used thick, so that the yellow salt will not spread.

TO MAKE COPYING INKS.

Dissolve in a pint and a half of writing ink (violet or any other color) an ounce of lump sugar or sugar candy. A copying ink, so slow drying that writing in it can be copied by the use of no greater pressure than the hand can produce when pa.s.sed over a sheet of paper, may be made by boiling away nearly half of some ordinary writing fluid and then adding as much glycerine.

A GOOD PASTER.

Let a little starch lie in vinegar over night. Pour in boiling water, stirring briskly till it thickens. It will keep better if a few drops of carbolic acid are added. A very little corrosive sublimate will keep out insects. A little glue dissolved in the vinegar will make it stronger. It leaves the pasted sc.r.a.p-page flexible, adheres firmly, dries quickly, and does not give a varnishy look to even the thinnest print paper.

A PASTE WHICH WILL NOT SPOIL.

A paste that will not spoil is made by dissolving a piece of alum the size of a walnut in one pint of water. Add to this two tablespoonfuls flour made smooth with a little cold water, and a few drops of oil of cloves, putting the whole to a boil. Put up in a gla.s.s canning-jar.

ELECTRIC PAPER.

Electric paper may be made thus:--Tissue paper or filtering paper is soaked in a mixture consisting of equal quant.i.ties of saltpetre and sulphuric acid. It is afterwards exposed to dry, when a pyroxyline (a substance resembling gun-cotton) forms. This is in the highest degree electrical.

A SILVER SOLDER.

To make silver solder melt together 34 parts, by weight, silver coin, and five parts copper; after cooling a little, drop into the mixture 4 parts zinc, then heat again.

AN ALLOY FOR GLa.s.s OR METAL.

The following alloy, it is said, will attach itself firmly to gla.s.s, porcelain or metal.--Twenty to thirty parts of finely pulverulent copper, prepared by precipitation or reduction with the battery, are made into a paste with oil of vitriol. To this seventy parts of mercury are added, and well triturated. The acid is then washed out with boiling water and the compound allowed to cool. In ten or twelve hours it becomes sufficiently hard to receive a brilliant polish, and to scratch the surface of tin or gold. When heated it is plastic, but does not contract on cooling.

AN IMPROVED PROCESS OF PHOTO-ENGRAVING.

The metal plate, of copper or zinc, is coated with a very thin layer of bitumen of Judaea, and when this coat has become perfectly dry, a film of bichromatized alb.u.men is flowed over the plate. It is next exposed in the camera, and afterwards washed with water, in order to dissolve all the alb.u.men which has not been rendered insoluble by the luminous action; it is then treated with spirit of turpentine, which dissolves all those parts of the layer of bitumen that have become exposed. The plate can now be attacked directly by water acidulated with from four to six per cent of nitric acid. The great advantage of this method consists in the high sensitiveness of the bichromatized alb.u.men, at the same time preserving the solid reserve produced by the bitumen of Judaea on a metallic surface.

TO MAKE NEW A CORRODED PEN.

When a pen has become so corroded as to be useless, it can be made good as new by holding it in the flame of a gas jet for half a minute; then drop in cold water, take out, wipe clean, and it will be ready for use again.

ENAMEL FOR FINE CARDS.

For the brilliant enamel now often generally applied to fine cards and other purposes, the following formula is given:--For white and for all pale and delicate shades, take twenty-four parts, by weight, of paraffine; add thereto 100 parts of pure kaolin (China clay), very dry and reduced to a fine powder. Before mixing with the kaolin, the paraffine must be heated to fusing point. Let the mixture cool, and it will form a h.o.m.ogeneous ma.s.s, which is to be reduced to powder, and worked into paste in a paint-mill, with warm water. This is the enamel ready for application. It can be tinted according to fancy.

ELECTROTYPING HANDWRITING.

To produce electrotypes or stereotypes of letters, signatures, ordinary written matter, drawings or sketches, coat a smooth surface of gla.s.s or metal with a smooth, thin layer of gelatine, and let it dry. Then write or draw upon it with an ink containing chrome alum, allow it to dry exposed to light, and immerse the plate in water. Those parts of the surface which have not been written upon will swell up and form a relief plate, while those parts which have been written upon with the chrome ink have become insoluble in water, after exposure to light. The relief may be transferred to plaster of Paris, and from this may be made a plate in type metal.

BLACK PAINT FOR BLACKBOARDS.