406 auripigmenta,

They readily melt over a gentle fire, running into a fine fluid mass of a deeper red,which colour the whole retains when cold ; if set on fire, it burns with a very brightand vivid greenish white flame, and a strong garlick-like smell, and finally leaves asmall quantity of greyish ashes, which taste very brackish and saline, but make noeffervescence with Aqua Fortis.

It is found in the Turkish dominions, and in the islands of the Archipelago, noris our own country without it, for I have lately receiv’d a very fine specimen of stfrom the tin mines of Cornwall, under the name of red Mundick, every thing that isbright and sparkling being there call’d by that name ; it is usually lodg’d in the greenZarnich, sometimes in but small quantities, sometimes in much larger; and in theislands of the Archipelago is sometimes, tho’ very rarely, found in pure masses com-pos’d of multitudes of spangles blended together in ail directions without the inter-vention of any other substance.

When pure it would doubtless make a very beautiful colour, but in its common stateof mixture with the green Zarnich, it is of little value.

These are the species of genuine Qrpiment known at present in the world, for I amnot, according to the common custom, accounting Sandarach of that number ; the con-founding these two substances under the fame denomination, is indeed an error of late ages,the Antients, who knew both Orpiment and Sandarach very well, never calling them bythe fame name ; and Diofcorides allotting them two separate chapters : What may there-fore appear a new discovery in regard to these bodies at this time, and set right their truenature and distinctions, was indeed well known to the Antients; and the great misfor-tune is, that the later writers, even those of greatest repute, have not taken the painsof enquiring thoroughly into the writings of the Antients, or of comparing their ac-counts with the bodies themselves ; the late eminent Geoffroy fays, fluid ft Auripig-mentum alterum Diofcoridis balanoides pallidum , colore Bandarachum imitans & glebofmn,ignoramus ; yet this very kind is evidently the red Orpiment, describ’d in this place.Dioscorides’s account of Orpiment is indeed an excellent one; he fays, the finest iscrustaceous or foliaceous, and resembles gold in colour, having its crusts laid evenlyand regularly on one another; and adds, that this kind is free from admixtures of anyforeign matter; there can be no doubt but that this was the fine, large, flaked Orpi-ment first describ’d; the other, he says, was form’d into irregular glebes in figureresembling the lumps of Ochre, and in colour approaching to Sandarach • this is thespecies declar’d unknown to us by Geoffroy, but is plainly this above describ’d; sothat a red Orpiment, different from Sandarach, tho’ it might seem a new discoverynow, is really a substance known as early as in the days of Diofcorides; and supposingthat author to have had before him some of the pure specimens, where the flakes arenot immers’d in the Zarnich, but make up of themselves the whole mass, it is noteasy to contrive in so few words a better description.

Simple inflammable Foflils.

SERIES I.

Class I. Order II. Genus I.

ZARNICHIA, ZARNICH S.

Inflammable Foflile substances , not compos d of plates or flakes , but of a plain , fimpkand uniform JtruFture , not flexile nor elastic , soluble in of and burning ’with a whitififlame , and noxious smell like that of Garlick.

r. Zarnichium fioride rubens ; quœ. Sandaracha author um.Bright red Zarnich , the Sandarach of Authors.

t A HIS is an extreamly beautiful and elegant Fossil, of a fine, even and compacttexture, and very remarkably heavy; it is of a bright glittering surface, very

smooth and soft to the touch, and very indeterminate in shape and size, being found of

all