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judged, the same effects. White wine produced an inkof a deeper black colour than the waters ; and with vine-gar, the colour was rather still deeper. Proof spirit ex-tracted only a reddiffi brown tinge, and rectified spirit apaler brown, the vitriol not being dissoluble in these li-quors. Both the spirituous tinctures funk and spread uponthe paper, that in rectified spirit more than the other:hence the addition of spirit to common ink, directed bysome for preserving it from mouldiness, or from freezingin winter, occasions generally a precipitation of partof the colour, and makes the, ink sink, more or less ac-cording to the quantity of the spirit. The coloured juicesof fruits, as of privet-berries, mulberries, black-cherries,used as menstruums for the galls and vitriol, made thecolour rather fuller on first writing than water did, but itwas less black, and soon grew dull or rusty in keeping.A decoction of logwood, used instead of water, sensiblyimproved both the beauty and the deepness of the black,without at all disposing it to fade.

Instead of the galls, I tried .other strong astringents, asoak bark, alder bark, sloe bark, sumach, tormentil root,bistort root, balaustine flowers, pomegranate peel, &c. butcould not find one of equal efficacy with galls. Nor,did any but the oak bark seem to give the same species ofblackness that galls did, most of the others having moreor less of a greenish hue : the oak bark itself however,though it came nearest to the galls, made a very bad ink,and though used in eight or ten times their quantity, wasfar from being equal to them in effect. The saw-dustof oak wood, which has lately been found to answer fortanning leather, as well as the bark or rather better, andconsequently to have no inconsiderable impregnation oftrue astringent matter, produced with vitriol a tincturesomewhat different from all the other astringents I have

tried: