Leuce is a change of the skin to a white colour, occasioned by a viscid and glutinous phlegm. Since all the kinds of leuce are not curable, you may form a diagnosis of it in this manner. Pierce the leuce superficially, not deeper than the skin, with a needle, and if blood flow, the complaint may be cured; but if a milky moisture be discharged, it is incurable. Or, rub it with a rough woollen rag, and if the part become red, the complaint may be cured; but if it remain of the same colour, it cannot be cured. And those kinds which attack a great part of the body are to be supposed more difficult to cure than those which are confined to a small space, and old cases than recent. Some, therefore, in leuce, have approved of burning by iron, consisting simply of the application of heat. Others, dreading the pain of burning, and the scar arising from it, as being no less unseemly than leuce itself, have had recourse to escharotic medicines, such as they say will produce a scar of the natural colour. Others rejecting all these things on account of the difficulty of their application, have used dyes (paying more consideration to the deception than the utility which they produce,) which are, of all others, the most to be rejected, owing to the speedy renewal of the affection. We must use, then, the under-mentioned remedial powers: Of adarce, of rosemary seed, of sulphur vivum, of each, equal parts; bruise and strain singly, and then, having triturated together for a sufficient number of days, anoint in the sun, but not in great quantity, lest the skin be ulcerated; and, after some time, a little hellebore and galls may be added in like manner.—_Another_: Macerate the tops of the black fig in vinegar, and having triturated, mix equal parts of aphronitrum, sulphur vivum, and the fruit of tamarisk, and having rubbed natron into the part, anoint and expose to the sun, taking care lest an ulcer be produced. But Archigenes having mixed a sufficiency of quicklime with fig-leaves, used them in like manner: or, he says, having rubbed the leuce with white hellebore until the part perspire and become of the same colour as the rest of the body, anoint with sinopis or melian earth; or, having perforated them with needles until they bleed, anoint with sinopis in vinegar; or, having first rubbed them as formerly said, anoint with the fresh juice of figs, or rub in so much with the leaves of it. * * * * *