By adding a small portion of sandarach varnish to the common sponge blacking it will make it brilliant and hard. By adding a small portion India-rubber dissolved in triple refined camphene it renders the blacking elastic and water-proof, and useful for boot and shoe uppers, etc.
Asphaltum is a smooth, hard, brittle, black substance, which breaks with a polish, melts easily when heated, and, when pure, burns without leaving any ashes. It makes a cheap and brilliant varnish for boot and shoe heels, by dissolving it in triple refined camphene. It should be made thick so as to spread with the finger or a brush.
India-rubber has been highly extolled for a varnish. Dissolve in five times its weight of triple refined camphene. By keeping it a few days, after it is cut fine, then boil one ounce of this solution in eight ounces of “drying” linseed oil, for a few minutes; strain the solution and use it warm.
WATER-PROOF CEMENT.
Take of the best glue four ounces, of isinglass two ounces, and dissolve them in mild ale over a slow fire, in a common glue kettle, to the consistence of strong glue, when one ounce and a half of well boiled linseed oil must be gradually added, and the whole be well mixed by stirring. When cold and made into cakes, it resembles India-rubber. When wanted for use dissolve a piece of it in a proportionate quantity of ale. This cement is applicable to all joints of wood, to join earthen-ware, china, glass. It is an excellent cement for leather, for harness, bands for machinery, &c. The joints of these are to be prepared as if for sewing, the cement to be applied hot, laying a weight upon each joint as it is made, in which state it is to be left six hours, when the joints will be found nearly as firm as if they were of an entire piece. By adding a little tow to the above, you have an excellent cement for leaks in casks, &c.
SEED-LAC VARNISH.
Take three ounces of seed-lac, and put it, with a pint of spirits of wine, into a bottle, of which it will not fill more than two-thirds. Shake the mixture well together, and place it in a gentle heat, till the seed-lac appears to be dissolved: the solution will be hastened by shaking the bottle occasionally. After it has stood some time, pour off the clear part, and keep it for use in a well-stopped bottle. The seed-lac should be purified before it is used, by washing it in cold water, and it should be in coarse powder, when added to the spirit.
This varnish is next to that of copal in hardness, and has a reddish-yellow color: it is, therefore, only to be used where a tinge of that kind is not injurious.
SHELLAC VARNISH.
Take five ounces of the best shellac, reduce it to a gross powder, and put it into a bottle in a gentle heat, or a warm, close apartment, where it must continue two or three days, but should be frequently well shaken. The lac will then be dissolved, and the solution should then be filtered through a flannel bag; and, when the portion that will pass through freely is come off, it should be kept for use in well-stopped bottles.