Tutia Pharm. Lond. & Edinb. Tutia alexandrina. Tutty: an argillaceous ore of zinc, found in Persia; formed on cylindrical moulds into tubulous pieces like the bark of a tree, and baked to a moderate hardnefs (a); generally of a brbwnish colour and full of small protuberances on the outside, smooth and yel-lowish. within, sometimes whitish, and some-times with a bluish call. Like other argillaceous bodies, it becomes harder in a strong fire; and after the zinc has been revived and dissipated by inflammable additions, or extracted by acids, the remaining earthy matter affords, with oil of vitriol, an aluminous salt (see Bolus and Calami-naris).

(a) Percival, Ess. Med, and Exp, II. 224.

Tutty, levigated into an impalpable powder, is, like the lapis calaminaris and calces of zinc, an useful ophthalmic, and frequently used as such in ointments and collyria. Ointments for this intention are prepared in the shops, by mixing the levigated tutty with so much sper-maceti ointment as is sufficient to reduce it to a due consistence†; or by adding one part to five parts of a simple liniment made of oil and wax ‡.