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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1878 Excerpt:...If it makes the glass swell and intumesco, it is properly prepared; if not, it must be still further calcined. Such a powder communicates to glass greens of various tints, passing into turquoiso. Whon thin narrow strips of brass are stratified with sulphur in a crucible, and calcined at a red heat, they becomo friable and may be reduced to powder. This being sifted and exposed upon tiles in a reverboratory furnaco for 10 or 12 days, becomes fit for use, and is capable of imparting a chalcedony--rod or yellow--tinge to glass by fusion, according to the mode and proportion of using it. The glassmakers rod colour may bo prepared by holding small plates of brass in a modorato hoat in a rovorberatory furnace till they are thoroughly calcined. When the substance becomes pulverulent, and assumes a rod colour, it is ready for immediate use. Brass colour, as employod by the colourmen to imitate brass, is of two tints--the red or bronze, and the yellow, liko gilt brass. Copper filings mixed with red ochre, or bole, constitute the former; a powdered brass, imported from Germany, is used for the latter. Both must be worked up with varnish after being dried by heat, and then spread flat with a camel-hair brush evenly upon tho surfaco of tho object. Tho best varnish is composed of 20 ounces of spirits of wine, 2 ounces of shellac, and 2 ouncos of sandaracn, properly dissolved. (See VAnxisH.) Only so much of the brass powder and varnish should bo mixed at a time as is wanted for immediate use. See Bkonzb Powdbh. BRASSES, COAX., or BRASS OF COAX, or BRASSBT COAX Karnes given to iron pyrites found in the coal-measures. In 1872 it was estimated that tho following quantities were produced and used:--Nobthumbebland and Durham.,. 3,250 tons. Yobkshikb 3,700 „ Lancashire 2...