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portions. If the galls are much increased, which it isnecessary they should be for ink, they make the dye inclineto brown; but an increase of the vitriol, by which inksare made so perishable, does not appear at all to affectthe dye : even the largest additions of vitriol, howeverthey may weaken the cloth, do not seem to injure thecolour.

14. In the dying of black, as of most other colours,there are considerable variations in the practices of diffe-rent workmen, which it would be difficult and even use-less to collect. I shall here describe two processes, whichI have often tried in small, and which appeared to me tobe the best.

II. Black with galls , logwood , and vitriol.

A hundred pounds of woollen cloth, dyed first to adeep blue, require, for the black dye, about five pounds ofvitriol, five of galls, and thirty of logwood. These, as Iam informed by an experienced artist, are the quantitiesgenerally allowed by our dyers.

The galls, beaten into moderately fine powder and tiedup in a bag, are boiled for a little time in a copper ofwater sufficient for working the cloth in. The bluedcloth, after being steeped in river water and drained, thatit may be every where thoroughly moist, but not so as todrip, is in this state put into the boiling decoction of thegalls, and kept turning therein for two hours or more,the bag of galls being now and then squeezed, that thevirtue of this drug may be more effectually extracted andcommunicated to the cloth.

The logwood, rasped or shaved into small chips, orrather ground into powder, is boiled in another copperfor several hours, this wood giving out its colour exceed-ing difficultly. The logwood liquor is most commonly

prepared