SABURRÆ s79

all the degrees of pale red from what we call flesh-colour’d to absolutely colourless; andthe brown particles which make its flight variegation, are more pellucid than the rest,of irregular figures, and of a brownish yellow ; among these there are scatter’d a fewspangles of a white foliaceous Talc, very thin, and in general smaller than the other par-ticles ; these are in reality very few in number, tho’ to an innacurate observer, the massto the naked eye may seem to contain a great number of them, many of its own particleshaving flat surfaces, and being very bright and colourless, and being not easily at first sightdistinguishable from Micæ; this is a mistake some have fallen into in regard to someof the common Sands of England, but there is much more ground for it here;

This raises no effervescence with Aqua Fortis.

It burns to a something paler red.

I receiv’d it from the shores of the Red Sea, where in some places there are long tractsof it, of four, five, or more feet in breadth running from the land into the sea; the oc-casion of this is easily guess’d, and I doubt not but there are Granites on that stioreof the fame colour.

8 . Saburra faxea^ crafjljfima splendida y carneo nigrescem.Large , coarse 3 blackish red , Jlony Grits*

This is extreamly large and coarse, and the most strongly variegated of all this Class jit is remarkably heavy, of a colour mix’d of pale red and black, and considerablybright and shining in its own particles, beside that, it is spangled with a small numberof black and white flakes of Talc which are in general smaller than the other particles ;its different matter is very irregular in size; it feels remarkably hard and cutting betweenthe fingers, and shook up in water subsides immediately, without leaving the leastmuddinest in it.

Examin’d before the Microscope, it appears a heap of large particles of various co-lours, shapes and sizes, some are white, others of all the degrees of a pale red, and agreat number perfectly black and shining more than the rest, tho' not at all pellucid jamong these there are flakes of a blackish, and some of a white foliaceous Talc.

It makes no effervescence with Aqua Fortis.

It suffers not the least change in the fire.

I receiv’d it from the shores of Sicily, where there is a prodigious bed of it whichruns to an unknown depth into the Sea.

g. Saburra saxea^ splendida , crajstjjima , rubro-virescens.

Coarse , shining , greenish-red , ftony Gritt.

This is an extreamly singular, and very bright and beautiful Gritt; it is very largeand coarse, considerably heavy, and of a greenish red; but compos’d of such largemasses, that like the former and some others, it is distinctly seen to be compos’d ofparticles of both those colours, and many white ones beside ; it is very bright and spark-ling in itself, and if closely examin’d is found to contain a few spangles of a greenishwhite Talc, very like the Venetian kind us’d in the shops; its particles, tho’ so variousin colour, are very uniform and regular in size; it feels very hard and sharp betweenthe fingers, and shook up in water subsides immediately, but leaves a reddish muddi-ness in it.

Examin’d by the Microscope, it appears compos’d of particles of very irregular si-p-ures, but all angular and all tending to flatness; they are green, white and red, allseeming of the same texture, and all equally transparent.

It makes a very brisk effervescence with Aqua Fortis. .

It burns to a pale reddish grey, with very little remaining greenest.

I had it from some of the shores of the Mediterranean, but could not learn the exactplace; by my enquiries about this, however, and all the others, I find they never coverwhole shores, but are always either in separate large patches, or in long trains from theland into the sea; this very well agrees with my opinion as to their origin; theymust in their concreted state, however, be many of them, particularly this, such veryelegant stones, that it is much to be wish’d they were traced out and taken no-tice of.

Sect,