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being made black; others are stained paler, with the fameliquor diluted with water, for making purple; and others,designed to be red, are prepared with a solution of alumand sugar of lead: all these colours are dyed in one andthe same copper of madder, with a heat a little below boil-ing: a boiling heat would, give a dark. tawney or blackishhue to the red, and therefore in this process must necessarilybe avoided;, but for the same reason it. would contributeto deepen the black, and therefore ought always to becalled in aid where thread, or entire pieces of linen orcotton, are to be dyed of this colour,.

SECT. XI..

The flaming of Wood, Ivory, Stones, (Sc. black.

I. Wood .

T HE staining of wood black, for picture frames, 6cc.

depends on the same principle with the black dyein the foregoing sections. For a deep black, the woodis brushed over four or five times with a. warm. decoctionof logwood, and afterwards as often with a. decoction ofgalls, being suffered to dry thoroughly between the severalapplications of the liquors : thus prepared, it. receives asine deep black colour, from being washed over with so-lution of vitriol; in the room of which, some use. a solu-tion of iron in vinegar, keeping the vinegar for thispurpose upon a quantity of the filings of the metal, andpouring off a little as it is wanted.. A pretty good blackis obtained also, more expeditioufly, by brushing overthe wood, first with. the logwood liquor, and afterwardswith common ink.

Plumier, in his Art de tournir, directs the wood to bepreviously washed twice with the second parting, water of

the.