a Narrative of the Turquois's changing Colour, that I cannot but think it worth your Peruſal, eſpecially ſince a much later and very Experienc'd Author, Olaus Wormius,[a]32] where he treats of that Stone, Confirms it with this Teſtimony. Imprimis memorandum exemplum quod Anſhelmus Boetius de ſeipſo refert, tam mutati Coloris, quam à caſu preſervationis. Cui & ipſe haud diſſimile adferre poſsum, niſi ex Anſhelmo petitum quis putaret. I remember that I ſaw two or three years ſince a Turcois (worn in a Ring) wherein there were ſome ſmall ſpots, which the Virtuoſo whoſe it was aſur'd me he had obſerv'd to grow ſometimes greater ſometimes leſs, and to be ſometimes in one part of the Stone, ſometimes in another. And I having encourag'd to make Pictures from time to time of the Stone, and of the Situation of the cloudy parts, thatſo their Motion may be more indiſputable, and better obſerv'd, he came to me about the midle of this very week, and aſſur'd me that he had, as I wiſh'd, made from time to time Schemes or Pictures of the differing parts of the Stone, whereby the ſeveral Removes and motions of the above mentioned Clouds are very manifeſt, though the cauſe ſeem'd to him very occult: theſe Pictures
he has promis'd to ſhow me, and is very ready to put the Stone it ſelf into my hands. But the ring having been the other day caſually broken upon his finger, unleſs it can be taken out, and ſet again without any conſiderable heat, he is loath to have it medled with, for fear its peculiarity ſhould be thereby deſtroy'd. And poſſibly his apprehenſion would have been ſtrengthen'd, if I had had opportunity to tell him what is related by the Learned Wormius[a]33] of an acquaintance of his, that had a Nephritick ſtone, of whoſe eminent Virtues he had often Experience ev'n in himſelf, and for that cauſe wore it ſtill about his Wriſt; and yet going upon a time into a Bath of fair Water only, wherein certain Herbs had been boyl'd, the Stone by being wetted with this decoction, was depriv'd of all his Virtue, whence Wormius takes Occaſion to advertiſe the ſick, to lay by ſuch ſtones whenſoever they make uſe of a Bath. And we might expect to find Turcos likewiſe, eaſily to be wrought upon in point of Colour, if that were true, which the curious Antonio Neri, in his ingenious Arte Vetraria[a]34] teaches of it, namely, That Turcois's diſcolour'd and grown white, will regain and acquire
an excellent Colour, if you but keep them two or three days at moſt cover'd with Oyl of ſweet Almonds kept in a temperate heat by warm aſhes, I ſay if it were true, becauſe I doubt whether it be ſo, and have not as yet had opportunity to ſatisfie my ſelf by Tryals, becauſe I find by the confeſſion of the moſt Skilfull Perſons among whom I have laid out for Turcoiſes, that the true ones are great rarities, though others be not at all ſo. And therefore I ſhall now only mind you of one thing that you know as well as I, namely, that the rare Stone which is called Oculus Mundi, if it be good in its Kind, will have ſo great a change made in its Texture by being barely left a while in the Languideſt of Liquors, common Waters, that from Opacous it will become Tranſparent, and acquire a Luſtre of which it will again be depriv'd, without uſing any other Art or Violence, by leaving it a while in the Air. And before experience had ſatisfy'd us of the truth of this, it ſeem'd as unlikely that common Water or Air, ſhould work ſuch great changes in that Gemm, as it now ſeems that the Effluviums of a human Body ſhould effect leſſer changes in a Turcois, eſpecially if more ſuſceptible of them, than other Stones of the ſame kind. But both my Watch and my Eyes tell me that
'tis now high time to think of going to ſleep, matters of this Nature, will be better, as well as more eaſily, clear'd by Conference, than Writing. And therefore ſince I think you know me too well to make it needfull for me to diſclame Credulity, notwithſtanding my having entertain'd you with all theſe Extravagancies; for you know well, how wide a difference I am wont to put betwixt things that barely may be, and things that are, and between thoſe Relations that are but not unworthy to be inquir'd into, and thoſe that are not worthy to be actually believ'd; without making Apologies for my Ravings, I ſhall readily comply with the drowſineſs that calls upon me to releaſe You, and the rather, becauſe Monſieur Zulichem being concern'd in your deſire to know the few things I have obſerved about the ſhining Stone. To entertain thoſe with Suſpicions that are accuſtomed not to acquieſce but in Demonſtrations, were a thing that cannot be look'd upon as other than very improper by,
SIR,
Your most Affectionate
and
most Faithfull Servant,
RO. BOYLE.
