A Recipe for Making Printers' Inks.—For black ink: Take of balsam of copaiba (pure), 9 ounces; lamp black, 3 ounces; indigo and Prussian blue, of each half an ounce; Indian red, 3/4 ounce; yellow soap (dry), 3 ounces; grind the mixture to an impalpable smoothness by means of a stone and muller. Canada balsam may be substituted for balsam of copaiba where the smell of the latter is objectionable, but the ink then dries very quickly. The red inks are similarly made by using such pigments as carmine, lakes, vermilion, chrome yellow, red lead, orange red, Indian red and Venetian red.
A Cement to Stick White Metal Tops on Glass Bottles.—One of the best cap cements consists of resin, 5 ounces; beeswax, 1 ounce; red ocher or Venetian red in powder, 1 ounce. Dry the earth thoroughly on a stove at a temperature above 212° Fah. Melt the wax and resin together, and stir in the powder by degrees. Stir until cold, lest the earthy matter settle to the bottom.
The Correct Meaning of the Tonnage of a Vessel.—The law defines very carefully how the tonnage of different vessels shall be calculated. An approximate rule for finding the gross tonnage is to multiply the length of keel between perpendiculars by the breadth of vessel and depth of hold, all in feet, and dividing the product by 100. It is generally assumed that 40 cubic feet shall constitute a ton, and the tonnage of a vessel is considered to be the multiple of this ton, which most closely corresponds with the internal capacity of the vessel.
A Recipe for Re-inking Purple Type Ribbons.—Use: Aniline violet, 1/4 ounce; pure alcohol, 15 ounces; concentrated glycerine, 15 ounces. Dissolve the aniline in the alcohol, and add the glycerine.
The Process of Giving a Tempered-Blue Color to the Steel Plate and Malleable Iron Castings of a Roller Skate.—In order to obtain an even blue, the work must have an even finish, and be made perfectly clean. Arrange a cast-iron pot in a fire so as to heat it to the temperature of melted lead, or just below a red heat. Make a flat bottom basket of wire or wire cloth to sit in the iron box, on which place the work to be blued, as many pieces as you may find you can manage, always putting in pieces of about the same thickness and size, so that they will heat evenly. Make a bail to the basket, so that it can be easily handled. When the desired color is obtained, dip quickly in hot water to stop the progress of the bluing, for an instant only, so that enough heat may be retained to dry the articles. A cover to the iron box may sometimes be used to advantage to hasten the heating. Another way, much used, is to varnish the work with ultramarine varnish, which may be obtained from the varnish makers.
Cement to Mend Iron Pots and Pans.—Take two parts of sulphur and one part, by weight, of fine black lead; put the sulphur in an old iron pan, holding it over the fire until it begins to melt, then add the lead; stir well until all is mixed and melted; then pour out on an iron plate or smooth stone. When cool, break into small pieces. A sufficient quantity of this compound being placed upon the crack of the iron pot to be mended, can be soldered by a hot iron in the same way a tinsmith solders his sheets. If there is a small hole in the pot, drive a copper rivet in it, and then solder over it with this cement. The Best Method of Rendering Basement Walls Damp-Proof.—Construct on the outside an area wall so that the earth does not rest directly against the main wall of the house, but only against the outside wall or casing of the area. To form such an area, build a wall half or one brick thick parallel to and some 2 or 3 inches from the main wall, and form at the bottom a channel or gutter connected with the drains, so that any moisture or water finding its way in through the outer casing may be conducted away and will not therefore penetrate into the building. Thoroughly ventilate the areas by means of air bricks or other suitable connections with the outer air, and connect with one another by making through connections underneath the floor joists. Be very careful that the main wall is laid on a good and efficient damp course. The top of the space between the area and main walls may be covered in all around the building with bricks—ornamented or otherwise, as preferred—on a line just above the ground. Another plan of effecting the same object is to dispense with the area wall and in building the brick work to cover the whole of the work on the outside with a thick layer of bituminous asphalt. The plaster on the inside is in this case often rendered in nearly neat Portland cement.
How to Caseharden Large Pieces of Steel.—A box of cast or wrought iron should be provided large enough to hold one or two of the pieces, with sufficient room all around to pack well with the casehardening materials, which may be leather scrap, hoof shavings, or horn shavings, slightly burned and pulverized, which may be mixed with an equal quantity of pulverized charcoal. Pack the pieces to be casehardened in the iron box so as not to touch each other or the box. Put an iron cover on the box and lute with clay. Heat gradually in a furnace to a full red, keep at an even temperature for from 2 to 4 hours, raise the heat to a cherry red during the last hour, then remove the cover and take out the pieces and plunge endwise vertically in water at shop temperature; 2 per cent. of hydrochloric acid in the water improves its tempering qualities and gives the metal an even gray color.
A Good and Cheap Preparation to Put on Friction Matches.—The igniting composition varies with different makers. The following recipes may be taken as fairly representative, the first being the best: 1. Phosphorus by weight, 1/2 part; potassium chlorate, 4 parts; glue, 2 parts; whiting, 1 part; finely powdered glass, 4 parts; water, 11 parts. 2. Phosphorus by weight, 2 parts; potassium chlorate, 5 parts; glue, 3 parts; red lead, 1-1/2 parts; water, 12 parts. 3. A German mixture for matches. Potassium chlorate, 7.8 parts; lead hyposulphite, 2.6 parts; gum arabic, 1 part.
To Find How Much Tin Vessels Will Hold.—For the contents of cylinders: Square the diameter, and multiply the product by 0.7854. Again, multiply by the height (all in inches). Divide the product by 231 for gallons. For the frustum of a cone: Add together the squares of the diameters of large and small ends; to this add the product of the diameter of the two ends. Multiply this sum by 0.7854. Multiply this product by the height (all in inches). Then divide by 231 for the number of gallons.
A Useful Recipe.—For stopping the joints between slates or shingles, etc., and chimneys, doors, windows, etc., a mixture of stiff white-lead paint, with sand enough to prevent it from running, is very good, especially if protected by a covering of strips of lead or copper, tin, etc., nailed to the mortar joints of the chimneys, after being bent so as to enter said joints, which should be scraped out for an inch in depth, and afterward refilled. Mortar protected in the same way, or even unprotected, is often used for the purpose, but it is not equal to the paint and sand. Mortar a few days old (to allow refractory particles of lime to slack), mixed with blacksmith's cinders and molasses, is much used for this purpose, and becomes very hard and effective.