the name of an instrument used for finding the bigness of fine round pearls. It consists of thin pieces or leaves, about two inches long, and half an inch broad, fastened together at one end by a rivet. In each of these are round holes drilled of different diameters. Those in the first leaf serve for measuring pearls from half a grain to seven grains; those of the second, for pearls from eight grains or two carats to five carats, &c.; and those of the third, for pearls from six carats and a half to eight carats and a half.
is also a sort of paint, varnish, or glue, used by painters, &c.
The shreds and parings of leather, parchment, or vellum, being boiled in water and strained, make size. This substance is much used in many trades.—The manner of using size is to melt some of it over a gentle fire; and scraping as much whiting into it as will just colour it, let them be well incorporated together; after which you may whiten frames, &c. with it. After it dries, melt the size again, and put more whiting and whiten the frames, &c. seven or eight times, letting it dry between each time: but before it is quite dry, between each washing with size, you must smooth and wet it over with a clean brush-pencil in fair water.
To make gold-size. Take gum-anime and asphaltum, of each one ounce; minium, licharge of gold, and amber, of each half an ounce: reduce all into a very fine powder, and add to them four ounces of linseed oil, and eight ounces of drying oil: digest them over a gentle fire that does not flame, so that the mixture may only simmer, but not boil; left it should run over and set the house on fire, stir it constantly with a stick till all the ingredients are diffused and incorporated, and do not leave off stirring till it becomes thick and ropy; after being sufficiently boiled, let it stand till it is almost cold, and then strain it through a coarse linen cloth, and keep it for use.—To prepare it for working, put what quantity you please in a horse-muffle shell, adding as much oil of turpentine as will dissolve it; and making it as thin as the bottom of your feed-lac varnish, hold it over a candle, and then strain it through a linen-rag into another shell; add to these as much vermilion as will make it of a darkish red; if it is too thick for drawing, you may thin it with some oil of turpentine. The chief use of this size is for laying on metals.
The best gold size for burnishing is made as follows: Take fine bole, what quantity you please; grind it finely on a piece of marble, then scrape into it a little beef fat; grind all well together; after which mix in a small proportion of parchment size, with a double proportion of water, and it is done.
To make silver-size. Take tobacco-pipe clay in fine powder, into which scrape some black-lead and a little Genoa soap, and grind them all together with parchment size as already directed.