LONDON,
Printed for Henry Herringman. 1664
A COPY
OF THE
LETTER
That Mr. Boyle wrote to Sir Robert Morray,
to accompany
the Observations touching
the Shining Diamond.
SIR,
Hough Sir Robert Morray and Monsieur Zulichem be Persons that have deserv'd so well of the Commonwealth of Learning, that I should think my self unworthy to be look'd upon as a Member of it, if I declin'd to Obey them, or to Serve them; yet I should not without Reluctancy send you the Notes, you desire for him, if I did not hope that you will transmit together with them, some Account why they are not less unworthy of his perusal; which, that you may do; I must inform you, how the writing of them was Occasion'd, which in short was thus. As I was just going out of Town, hearing that an Ingenious Gentleman of my Acquaintance, lately return'd from Italy, had a Diamond, that being rubb'd, would shine in the Dark, and that he was not far off, I snatch'd time from my Occasions to make him a Visit, but finding him ready to go abroad, and having in vain try'd to make the Stone yield any Light in the Day time, I borrow'd it of him for that Night, upon condition to restore it him within a Day or two at furthest, at Gresham College, where we appointed to attend the meeting of the Society, that was then to be at that place. And hereupon I hasted that Evening out of Town, and finding after Supper that the Stone which in the Day time would afford no discernable Light, was really Conspicuous in the Dark, I was so taken with the Novelty, and so desirous to make some use of an opportunity that was like to last so little a while, that though at that time I had no body to assist me but a Foot-Boy, yet sitting up late, I made a shift that Night to try a pretty number of such of the things that then came into my thoughts, as were not in that place and time unpracticable. And the next Day being otherwise imploy'd, I was fain to make use of a drowsie part of the Night to set down hastily in Writing what I had observ'd, and without having the time in the Morning, to stay the transcribing of it, I order'd the Observations to be brought after me to Gresham College, where you may remember, that they were together with the Stone it self shown to the Royal Society, by which they had the good Fortune not to be dislik'd, though several things were through hast omitted, some of which you will find in the Margin of the inclosed Paper. The substance of this short Narrative I hope you will let Monsieur Zulichem know, that he may be kept from expecting any thing of finish'd in the Observations, and be dispos'd to excuse the want of it. But such as they are, I hope they will prove (without a Clinch) Luciferous Experiments, by setting the Speculations of the Curious on work, in a diligent Inquiry after the Nature of Light, towards the discovery of which, perhaps they have not yet met with so considerable an Experiment, since here we see Light produc'd in a dead and opacous Body, and that not as in rotten Wood, or in Fishes, or as in the Bolonian Stone, by a Natural Corruption, or by a Violent Destruction of the Texture of the Body, but by so slight a Mechanical operation upon its Texture, as we seem to know what it is, and as is immediately perform'd, and that several wayes without at all prejudicing the Body, or making any sensible alterations in its Manifest Qualities. And I am the more willing to expose my hasty Tryals to Monsieur Zulichem, and to You, because, he being upon the Consideration of Dioptricks, so odd a Phœnomemon relateing to the Subject, as probably he treats of, Light will, I hope, excite a person to consider it, that is wont to consider things he treats of very well. And for you Sir, I hope you will both recrute and perfect the Observations you receive, For you know that I cannot add to them, having a good while since restor'd to Mr. Clayton the Stone, which though it be now in the hands of a Prince that so highly deserves, by understanding them, the greatest Curiosities; yet he vouchsafes you that access to him as keeps me from doubting, you may easily obtain leave to make further Tryals with it, of such a Monarch as ours, that is not more inquisitive himself, than a favourer of them that are so. I doubt not but these Notes will put you in mind of the Motion you made to the Society, to impose upon me the Task of bringing in, what I had on other occasions observ'd concerning shining Bodies. But though I deny not, that I sometimes made observations about the Bolonian Stone, and try'd some Experiments about some other shining Bodies; Yet the same Reasons that reduc'd me then to be unwilling to receive ev'n their commands, must now be my Apology for not answering your Expectations, Namely the abstruse nature of Light, and my being already over-burden'd, and but too much kept imploy'd by the Urgency of the Press, as well as by more concerning and distracting Occasions. But yet I will tell you some part of what I have met with in reference to the Stone, of which I send you an account. Because I find on the one side, that a great many think it no Rarity upon a mistaken perswasion, that not only there are store of Carbuncles, of which this is one; but that all Diamonds and other Glistering Jewels shine in the Dark. Whereas on the other side there are very Learn'd Men, who (plausibly enough) deny that there are any Carbuncles or shining Stones at all.
And certainly, those Judicious men have much more to say for themselves, than the others commonly Plead, and therefore did deservedly look upon Mr. Clayton's Diamond as a great Rarity. For not only Boetius de Boot, who is judg'd the best Author on this Subject, ascribes no such Virtue to Diamonds, but begins what he delivers of Carbuncles, with this passage.26 Magna fama est Carbunculi. Is vulgo putatur in tenebris Carbonis instar lucere; fortassis quia Pyropus seu Anthrax appellatus a veteribus fuit. Verum hactenus nemo nunquam verè asserere ausus fuit, se gemmam noctu lucentem vidisse. Garcias ab Horto proregis Indiæ Medicus, refert se allocutum fuisse, qui se vidisse affirmarent. Sed iis fidem non habuit. And a later Author, the Diligent and Judicious Johannes de Laet in his Chapter of Carbuncles and of Rubies, has this passage. Quia autem Carbunculi, Pyropi & Anthraces a veteribus nominantur, vulgo creditum fuit, Carbonis instar in tenebris lucere, quod tamen nullâ gemmâ hastenus deprehensum, licet à quibusdam temerè jactetur. And the recentest Writer I have met with on this Subject, Olaus Wormius, in his Account of his well furnish'd Musæum, do's, where he treats of Rubies, concurr with the former Writers by these Words.27 Sunt qui Rubinum veterum Carbunculum esse existimant, sed deest una illa nota, quod in tenebris instar Anthracis non luceat: Ast talem Carbunculum in rerum naturâ non inveniri major pars Authoram existimant. Licet unum aut alterum in India apud Magnates quosdam reperiri scribant, cum tamen ex aliorum relatione id habeant saltem, sed ipsi non viderint. In confirmation of which I shall only add, that hearing of a Rubie, so very Vivid, that the Jewellers themselves have several times begg'd leave of the fair Lady to whom it belong'd, that they might try their choicest Rubies by comparing them with That, I had the Opportunity by the Favour of this Lady and her Husband, (both which I have the Honour to be acquainted with) to make a Trial of this famous Rubie in the Night, and in a Room well Darkn'd, but not only could not discern any thing of Light, by looking on the Stone before any thing had been done to it, but could not by all my Rubbing bring it to afford the least Glimmering of Light.
But, Sir, though I be very backward to admit strange things for truths, yet I am not very forward to reject them as impossibilities, and therefore I would not discourage any from making further Inquiry, whether or no there be Really in Rerum natura, any such thing as a true Carbuncle or Stone that without Rubbing will shine in the Dark. For if such a thing can be found, it may afford no small Assistance to the Curious in the Investigation of Light, besides the Nobleness and Rarity of the thing it selfe. And though Vartomannus was not an Eye witness of what he relates, that the King of Pegu, one of the Chief Kings of the East-Indies, had a true Carbuncle of that Bigness and Splendour, that it shin'd very Gloriously in the Dark, and though Garcias ab Horto, the Indian Vice-Roys Physician, speaks of another Carbuncle, only upon the Report of one, that he Discours'd with, who affirmed himself to have seen it; yet as we are not sure that these Men that gave themselves out to be Eye-witnesses speak true, yet they may have done so for ought we know to the contrary. And I could present you with a much considerabler Testimony to the same purpose, if I had the permission of a Person concern'd, without whose leave I must not do it. I might tell you that Marcus Paulus Venetus28 (whose suppos'd Fables, divers of our later Travellours and Navigatours have since found to be truths) speaking of the King of Zeilan that then was, tells us, that he was said to have the best Rubie in the World, a Palm long and as big as a mans Arm, without spot, shining like a Fire, and he subjoyns, that the Great Cham, under whom Paulus was a considerable Officer, sent and offer'd the value of a City for it; But the King answer'd, he would not give it for the treasure of the World, nor part with it, having been his Ancestours. And I could add, that in the Relation made by two Russian Cossacks of their Journey into Catay29, written to their Emperour, they mention'd their having been told by the people of those parts, that their King had a Stone, which Lights as the Sun both Day and Night, call'd in their Language Sarra, which those Cossacks interpret a Ruby. But these Relations are too uncertain for me to build any thing upon, and therefore I shall proceed to tell you, that there came hither about two years since out of America, the Governour of one of the Principal Colonies there, an Ancient Virtuoso, and one that has the Honour to be a member of the Royal Society; this Gentleman finding some of the chief Affairs of his Country committed to another and me, made me divers Visits, and in one of them when I enquir'd what Rare Stones they had in those parts of the Indies he belong'd to, he told me, that the Indians had a Tradition that in a certain hardly accessible Hill, a pretty way up in the Country, there was a Stone which in the Night time shin'd very vividly, and to a great distance, and he assur'd me, that though he thought it not fit to venture himself so far among those Savages, yet he purposely sent thither a bold Englishman, with some Natives to be his guides, and that this Messenger brought him back word, that at a distance from the Hillock he had plainly perceiv'd such a shining Substance as the Indians Tradition mention'd, and being stimulated by Curiosity, had slighted those Superstitious Fears of the Inhabitants, and with much ado by reason of the Difficulty of the way, had made a shift to clamber up to that part of the Hill, where, by a very heedful Observation, he suppos'd himself to have seen the Light: but whether 'twere that he had mistaken the place, or for some other Reason, he could not find it there, though when he was return'd to his former Station, he did agen see the Light shining in the same place where it shone before. A further Account of this Light I expect from the Gentleman that gave me this, who lately sent me the news of his being landed in that Country. And though I reserve to my self a full Liberty of Believing no more than I see cause; yet I do the less scruple to relate this, because a good part of it agrees well enough with another Story that I shall in the next place have occasion to subjoyn, in order whereunto I shall tell you, that though the Learned Authors I formerly mention'd, tell us, that no Writer has affirm'd his having himself seen a real Carbuncle, yet, considering the Light of Mr. Claytons Diamond, it recall'd into my mind, that some years before, when I was Inquisitive about Stones, I had met with an old Italian Book highly extoll'd to me by very competent Judges, and that though the Book were very scarce, I had purchas'd it at a dear Rate, for the sake of a few considerable passages I met with in it, and particularly one, which being very remarkable in it self, and pertinent to our present Argument, I shall put it for you, though not word for word, which I fear I have forgot to do, yet as to the Sense, into English.
Having promis'd (Says our Author)30 to say something of that most precious sort of Jewels, Carbuncles, because they are very rarely to be met with, we shall briefly deliver what we know of them. In Clement the seventh's time, I happen'd to see one of them at a certain Ragusian Merchants, nam'd Beigoio di Bona, This was a Carbuncle white, of that kind of whiteness which we said was to be found in those Rubies of which we made mention a little above, (where he had said that those Rubies had a kind of Livid Whiteness or Paleness like that of a Calcidonian) but it had in it a Lustre so pleasing and so marveilous, that it shin'd in the Dark, but not as much as colour'd Carbuncles, though it be true, that in an exceeding Dark place I saw it shine in the manner of fire almost gone out. But as for colour'd Carbuncles, it has not been my Fortune to have seen any, wherefore I will onely set down what I Learn'd about them Discoursing in my Youth with a Roman Gentleman of antient Experience in matters of Jewels, who told me, That one Jacopo Cola being by Night in a Vineyard of his, and espying something in the midst of it, that shin'd like a little glowing Coal, at the foot of a Vine, went near towards the place where he thought himself to have seen that fire, but not finding it, he said, that being return'd to the same place, whence he had first descry'd it, and perceiving there the same splendor as before, he mark'd it so heedfully, that he came at length to it, where he took up a very little Stone, which he carry'd away with Transports and Joy. And the next day carrying it about to show it divers of his Friends, whilst he was relating after what manner he found it, there casually interven'd a Venetian Embassadour, exceedingly expert in Jewels, who presently knowing it to be a Carbuncle, did craftily before he and the said Jacopo parted (so that there was no Body present that understood the Worth of so Precious a Gemm) purchase it for the Value of 10. Crowns, and the next day left Rome to shun the being necessitated to restore it, and (as he affirm'd) it was known within some while after that the said Venetian Gentleman did in Constantinople sell that Carbuncle to the then Grand Seignior, newly come to the Empire, for a hundred thousand Crowns. And this is what I can say concerning Carbuncles, and this is not a little at least as to the first part of this account, where our Cellini affirms himself to have seen a Real Carbuncle with his own Eyes, especially since this Author appears wary in what he delivers, and is inclin'd rather to lessen, than increase the wonder of it. And his Testimony is the more considerable, because though he were born a Subject neither to the Pope nor the then King of France (that Royal Virtuoso Francis the first) yet both the one and the other of those Princes imploy'd him much about making of their Noblest Jewels. What is now reported concerning a Shining Substance to be seen in one of the Islands about Scotland, were very improper for me to mention to Sr. Robert Morray, to whom the first Information was Originally brought, and from whom I expect a farther (for I scarce dare expect a convincing) account of it. But I must not omit that some Virtuoso questioning me the other day at White-Hall about Mr. Claytons Diamond, and meeting amongst them an Ingenious Dutch Gentleman, whose Father was long Embassador for the Netherlands in England, I Learn'd of him, that, he is acquainted with a person, whose Name he told (but I do not well remember it) who was Admiral of the Dutch in the East-Indies, and who assur'd this Gentleman Monsieur Boreel, that at his return from thence he brought back with him into Holland a Stone, which though it look'd but like a Pale Dull Diamond, such as he saw Mr. Claytons to be, yet was it a Real Carbuncle, and did without rubbing shine so much, that when the Admiral had occasion to open a Chest which he kept under Deck in a Dark place, where 'twas forbidden to bring Candles for fear of Mischances, as soon as he open'd the Trunck, the Stone would by its Native Light, shine so as to Illustrate a great part of it, and this Gentleman having very civilly and readily granted me the request I made him, to Write to the Admiral, who is yet alive in Holland, (and probably may still have the Jewel by him,) for a particular account of this Stone, I hope ere long to receive it, which will be the more welcome to me, not onely because so unlikely a thing needs a cleer evidence, but because I have had some suspition of that (supposing the truth of the thing) what may be a shining Stone in a very hot Countrey as the East-Indies, may perhaps cease to be so (at least in certain seasons,) in one as cold as Holland. For I observ'd in the Diamond I send you an account of, that not onely rubbing but a very moderate degree of warmth, though excited by other wayes, would make it shine a little. And 'tis not impossible that there may be Stones as much more susceptible than that, of the Alterations requisite to make a Diamond shine, as that appeares to be more susceptible of them, than ordinary Diamonds. And I confess to you, that this is not the only odd suspition (for they are not so much as conjectures) that what I try'd upon this Diamond suggested to me. For not here to entertain you with the changes I think may be effected ev'n in harder sorts of Stones, by wayes not vulgar, nor very promising, because I may elsewhere have occasion to speak of them, and this Letter is but too Prolix already, that which I shall now acknowledge to you is, That I began to doubt whether there may not in some Cases be some Truth in what is said of the right Turquois, that it often changes Colour as the wearer is Sick or Well, and manifestly loses its splendor at his Death. For when I found that ev'n the warmth of an Affriction that lasted not above a quarter of a minute, Nay, that of my Body, (whose Constitution you know is none of the hottest) would make a manifest change in the solidest of Stones a Diamond, it seem'd not impossible, that certain warm and Saline steams issuing from the Body of a living man, may by their plenty or paucity, or by their peculiar Nature, or by the total absence of them, diversifie the Colour, and the splendor of so soft a Stone as the Turquois. And though I admir'd to see, that I know not how many Men otherwise Learn'd, should confidently ascribe to Jewels such Virtues as seem no way competible to Inanimate Agents, if to any Corporeal ones at all, yet as to what is affirm'd concerning the Turquois's changing Colour, I know not well how to reject the Affirmation of so Learned (and which in this case is much more considerable) so Judicious a Lapidary as Boetius de Boot31, who upon his own particular and repeated Experience delivers so memorable 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,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 Wormius33 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 Vetraria34 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.
OBSERVATIONS
Made this 27th.35 of October 1663. about Mr. Clayton's Diamond.36
Being look'd on in the Day time, though in a Bed, whose Curtains were carefully drawn, I could not discern it to Shine at all, though well Rubb'd, but about a little after Sun-set, whilst the Twilight yet lasted, Nay, this Morning37 a pretty while after Sun-rising, (but before I had been abroad in the more freely inlightned Air of the Chamber) I could upon a light Affriction easily perceive the Stone to Shine.
Secondly, The Candles being removed, I could not in a Dark place discern the Stone to have any Light, when I looked on it, without having Rubb'd or otherwise prepar'd it.
Thirdly, By two white Pibbles though hard Rubb'd one against another, nor by the long and vehement Affriction of Rock Crystal against a piece of Red cloath, nor yet by Rubbing two Diamonds set in Ring, as I had Rubb'd this Stone, I could produce any sensible degree of Light.
Fourthly, I found this Diamond hard enough, not only to enable me to write readily with it upon Glass, but to Grave on Rock Crystal it self.
Fifthly, I found this to have like other Diamonds, an Electrical faculty.38
Sixthly, Being rubb'd upon my Cloaths, as is usual for the exciting of Amber, Wax, and other Electrical Bodies, it did in the Dark manifestly shine like Rotten Wood, or the Scales of Whitings, or other putrified Fish.
Seventhly, But this Conspicuousness was Fainter than that of the Scales, and Slabber (if I may so call it) of Whitings, and much Fainter than the Light of a Glow-worm, by which I have been sometimes able to Read a short Word, whereas after an ordinary Affriction of this Diamond I was not able to discern distinctly by the Light of it any of the nearest Bodies: And this Glimmering also did very manifestly and considerably Decay presently upon the ceasing of the Affriction, though the Stone continued Visible some while after.
Eighthly, But if it were Rubb'd upon a convenient Body for a pretty while, and Briskly enough, I found the Light would be for some moments much more considerable, almost like the Light of a Glow-worm, insomuch after I ceased Rubbing, I could with the Chaf'd stone exhibit a little Luminous Circle, like that, but not so bright as that which Children make by moving a stick Fir'd at the end, and in this case it would continue Visible about seven or eight times as long as I had been in Rubbing it.
Ninthly, I found that holding it a while near39 the Flame of a Candle, (from which yet I was carefull to avert my Eyes) and being immediately remov'd into the Dark, it disclosed some faint Glimmering, but inferiour to that, it was wont to acquire by Rubbing. And afterward holding it near a Fire that had but little Flame, I found the Stone to be rather less than more excited, than it had been by the Candle.
Tenthly, I likewise indeavour'd to make it Shine, by holding it a pretty while in a very Dark place, over a thick piece of Iron, that was well Heated, but not to that Degree as to be Visibly so. And though at length I found, that by this way also, the Stone acquired some Glimmering, yet it was less than by either of the other ways above mention'd.
Eleventhly, I also brought it to some kind of Glimmering Light, by taking it into Bed with me, and holding it a good while upon a warm part of my Naked Body.
Twelfthly, To satisfie my self, whether the Motion introduc'd into the Stone did generate the Light upon the account of its producing Heat there, I held it near the Flame of a Candle, till it was qualify'd to shine pretty well in the Dark, and then immediately I apply'd a slender Hair to try whether it would attract it, but found not that it did so; though if it were made to shine by Rubbing, it was as I formerly noted Electrical. And for further Confirmation, though I once purposedly kept it so near the hot Iron I just now mention'd, as to make it sensibly Warm, yet it shin'd more Dimly than it had done by Affriction or the Flame of a Candle, though by both those ways it had not acquir'd any warmth that was sensible.
Thirteenthly, Having purposely rubb'd it upon several Bodies differing as to Colour, and as to Texture, there seem'd to be some little Disparity in the excitation (if I may so call it) of Light. Upon White and Red Cloths it seem'd to succeed best, especially in comparison of Black ones.
Fourteenthly, But to try what it would do rubb'd upon Bodies more hard, and less apt to yield Heat upon a light Affriction, than Cloath, I first rubb'd it upon a white wooden Box, by which it was excited, and afterwards upon a piece of purely Glazed Earth, which seem'd during the Attrition to make it Shine better than any of the other Bodies had done, without excepting the White ones, which I add, lest the Effect should be wholly ascrib'd to the disposition White Bodies are wont to have to Reflect much Light.
Fifteenthly, Having well excited the Stone, I nimbly plung'd it under Water40, that I had provided for that purpose, and perceiv'd it to Shine whilst it was beneath the Surface of that Liquor, and this I did divers times. But when I indeavour'd to produce a Light by rubbing it upon the lately mentioned Cover of the Box, the Stone and it being both held beneath the Surface of the Water, I did not well satisfie my self in the Event of the Trial; But this I found, if I took the Stone out, and Rubb'd it upon a piece of Cloath, it would not as else it was wont to do, presently acquire a Luminousness, but needed to be rubb'd manifestly much longer before the desired Effect was found.
Sixteenthly, I also try'd several times, that by covering it with my warm Spittle (having no warm Water at hand) it did not lose his Light.41
Seventeenthly, Finding that by Rubbing the Stone with the Flat side downwards, I did by reason of the Opacity of the Ring; and the sudden Decay of Light upon the ceasing of the Attrition, probably lose the sight of the Stones greatest Vividness; and supposing that the Commotion made in one part of the stone will be easily propagated all over, I sometimes held the piece of Cloath upon which I rubb'd it, so, that one side of the Stone was exposed to my Eye, whilst I was rubbing the other, whereby it appear'd more Vivid than formerly, and to make Luminous Tracts by its Motions too and fro. And sometimes holding the Stone upwards, I rubb'd its Broad side with a fine smooth piece of Transparent Horn, by which means the Light through that Diaphanous Substance, did whilst I was actually rubbing the Stone, appear so Brisk that sometimes and in some places it seem'd to have little Sparks of fire.
Eighteenthly, I took also a piece of flat Blew Glass, and having rubb'd the Diamond well upon a Cloath, and nimbly clapt the Glass upon it, to try whether in case the Light could peirce it, it would by appearing Green, or of some other Colour than Blew, assist me to guess whether it self were sincere or no. But finding the Glass impervious to so faint a Light, I then thought it fit to try whether that hard Bodies would not by Attrition increase the Diamonds Light so as to become penetrable thereby, and accordingly when I rubb'd the Glass briskly upon the Stone, I found the Light to be Conspicuous enough, and somewhat Dy'd in its passage, but found it not easie to give a Name to the Colour it exhibited.
Lastly, To comply with the Suspition I had upon the whole Matter, that the chief manifest Change wrought in the Stone, was by Compression of its parts, rather than Incalescence, I took a piece of white Tile well Glaz'd, and if I press'd the Stone hard against it, it seem'd though I did not rub it to and fro, to shine at the Sides: And however it did both very manifestly and vigorously Shine, if whilst I so press'd it, I mov'd it any way upon the Surface of the Tile, though I did not make it draw a Line of above a quarter of an Inch long, or thereabouts. And though I made it not move to and fro, but only from one end of the short Line to the other, without any return or Lateral motion. Nay, after it had been often rubb'd, and suffer'd to lose its Light again, not only it seem'd more easie to be excited than at the beginning of the Night; but if I did press hard upon it with my Finger, at the very instant that I drew it briskly off, it would disclose a very Vivid but exceeding short Liv'd Splendour, not to call it a little Coruscation.42 So that a Cartesian would scarce scruple to think he had found in this Stone no slight Confirmation of his Ingenious Masters Hypothesis, touching the Generation of Light in Sublunary Bodies, not sensibly Hot.
A Postscript.
Annexed some Hours after the
Observations were Written.
So many particulars taken notice of in one Night, may make this Stone appear a kind of Prodigie, and the rather, because having try'd as I formerly noted, not only a fine Artificial Crystal, and some also that is Natural, but a Ruby and two Diamonds, I did not find that any of these disclos'd the like Glimmering of Light;43 yet after all, perceiving by the Hardness, and the Testimony of a Skilfull Goldsmith, that this was rather a Natural than Artificial Stone; for fear lest there might be some difference in the way of Setting, or in the shape of the Diamonds I made use of, neither of which was like this, a flat Table-stone, I thought fit to make a farther Trial of my own Diamonds, by such a brisk and assiduous Affriction as might make amends for the Disadvantages above-mention'd, in case they were the cause of the unsuccessfulness of the former Attempts: And accordingly I found, that by this way I could easily bring a Diamond I wore on my Finger to disclose a Light, that was sensible enough, and continued so though I cover'd it with Spittle, and us'd some other trials about it. And this will much lessen the wonder of all the formerly mention'd Observations, by shewing that the properties that are so strange are not peculiar to one Diamond, but may be found in others also, and perhaps in divers other hard and Diaphanous Stones. Yet I hope that what this Discovery takes away from the Wonder of these Observations, it will add to the Instructiveness of them, by affording pregnants Hints, towards the Investigation of the Nature of Light.
FINIS.
Notes.
1 L. Annæ Senecæ Natur. Quest. l. 6. c. 5.
2 He that desires more instances of this kind and matter, that according to this doctrine may much help the Theory of colours, and particularly the force both of Sulphureous and volatile, is likewise of Alcalizate and Acid Salts, and in what particulars, Colours likely depend not in the causation from any Salt at all, may beg his information from M. Boyle who hath some while since honoured me with the sight of his papers concerning this subject, containing many excellent experiments, made by him for the Elucidation of this doctrine, &c Dr. R. Sharrock in his ingenious and usefull History of the Propagation and Improvement of Vegetables, published in the yeare 1660.
3 See the Discourse of the Nature of Whiteness and Blackness.
4 Since for his eminent Qualities and Loyalty Grac'd, by his Majesty, with the Honour of Knighthood.
5 Exercitat. 325 Parag. 4
6 Album quippe & agrum, hoc quidem asperum esse dicit, hoc vero læve. de Sensu & Sensib. 3. 3.
7 Epist. 2. pag. 45.
8 Gent. Septen. Histor. lib. 4 cap. 13.
9 Hist. Anatom. Cent. 3. Hist. 44.
10 Olearius Voyage de Mosco. et de Perse liv. 3.
11 Piso Nat. & Med. Hist. Brasil. lib 1. in fine.
12 Purchas Pilgrim. Second part, Seventh Book 3. Chap. Sect 5.
13 Purchas. Ibid.
14 Purchas Ibid. in fin
15 See Scaliger Exercit. 325. Sect. 9.
16 Nicolaus Monardes lib simplic. ex India allatis, cap. 27.
17 Kircher. Art. Mag. lucis & umbræ, lib. 1. part. 3.
18 Herbarists are wont to call this Plant Cyanus vulgaris minor.
19 Paracelsus de Mineral. tract. 1. pag. m. 243
20 See Parkinson Th. Boran. Trib. 9. cap. 26.
21 Parkinson, Thea. Bot. Trib. 4 cap. 12.
22 Beguinus, Tyr. Chy. Lib. 2º. Cap. 13º.
23 Libr. 2do Cap. 34.
24 See the latter end of the fiftieth Experiment.
25 The Curious Reader that desires further Information concerning Lakes, may Resort to the 7th Book of Neri's Art of Glass, Englished (6 or 7 years since the Writing of this 49th Experiment) and Illustrated with Learned Observations, by the Inquisitive and experienc'd Dr. Charles Merret.
26 Boetius de Boot. Gem. & Lapid. Histor. Lib. 3. Cap. 8.
27 Musæi Wormiani. Cap. 17.
28 Purchas's Pilgrim. lib. 1. cap. 4. pag. 104.
29 In the year 1619.
30 Benvonuto Cellini nell Arte del Gioiellare, Lib. 1. pag. 10.
31 The Narrative in the Authors own words, is this. Ego (sayes he) sanctè affirmare possum me unam aureo Annulo inclusam perpetuo gestare, cujus facultatem (si gemmæ est) nunquam satis admirari potui. Gestaverat enim ante Triginta annos Hispanus quidam non procula puternis ædibus habitans. Is cum vitâ functus esset, & ipsius suspellex (ut moris apud nos est) venum exposita esset, inter cætera etiam Turcois exponebatur. Verum nemo (licet complures eo concurrissent, ut eam propter Coloris Elegantiam, quam vivo Domino habuerat emerent) sibi emptam voluit, pristinum enim nitorem & Colorem prorsus amiserat, ut potius Malachites, quam Turcois videretur. Aderat tum temporis gemmæ habendæ desiderio etiam parens & frater meus, qui antea sæpius gratiam & elegantiam ipsius viderant, mirabundi eam nunc tam esse deformem, Emit eam nihilominus pater, satisque vili pretio, qua omnibus contemptui erat, ac presentes non eam esse quam Hispanus gestarat, arbitrarentur. Domum reversus Pater, qui tam turpem Gemmam gestare sibi indecorum putabat, eam mihi dono dat, inquiens; Quandoquidem, fili mi, vulgi fama est, Turcoidem, ut facultates suas exercere possit, dono dari debere tibi eam devoveo, ego acceptam Gemmam sculptori trado, at gentilitia mea insignia illi, quamadmodum fieri solet, in Jaspide Chalcedono, aliisque Ignobilioribus Gemmis, insculperat. Turpe enim existimabam, hujusmodi Gemmâ ornatus gratia, dum gratiam nullam haberet, uti. Paret Sculptor redditque Gemmam, quam gesto pro annulo Signatorio. Vix per mensem gestaram, redit illi pristinus color, sed non ita nitens propter Sculpturam, ac inæqualem superficiem. Miramur omnes gemmam, atque id præcipuè quod color indies pulchrior fieret. Id quià observabam, nunquam fere eam à manu deposui, ita ut nunc adhuc candem gestem.
32 Olaus Wormius, in Musæ. 18º pag. 186.
33 Musæ. Worm. pag. 99.
34 Arte Vetraria, lib. 7 cap. 102.
35 These were brought in and Read before the Royal Society, (the Day following) Oct. 28. 1663.
36 The Stone it self being to be shown to the Royal Society, when the Observations were deliver'd, I was willing (being in haste) to omit the Description of it, which is in short, That it was a Flat or Table Diamond, of about a third part of an Inch in length, and somewhat less in breadth, that it was a Dull Stone, and of a very bad Water, having in the Day time very little of the Vividness of ev'n ordinary Diamonds, and being Blemished with a whitish Cloud about the middle of it, which covered near a third part of the Stone.
37 Hast made me forget to take notice that I went abroad the same Morning, the Sun shining forth clear enough, to look upon the Diamond though a Microscope, that I might try whether by that Magnifying Glass any thing of peculiar could be discern'd in the Texture of the Stone, and especially of the whitish Cloud that possest a good part of it. But for all my attention I could not discover any peculiarity worth mentioning.
38 V. For it drew light Bodies like Amber, Jet, and other Concretes that are noted to do so; But its attractive power seem'd inferiour to theirs.
39 IX. We durst not hold it in the Flame of a Candle, no more than put it into a naked Fire; For fear too Violent a Heat (which has been observ'd to spoil many other precious Stones) should vitiate and impair a Jewel, that was but borrow'd, and was suppos'd to be the only one of its Kind.
40 XV. We likewise Plung'd it as soon as we had excited it, under Liquors of several sorts, as Spirit of Wine, Oyl both Chymical and express'd, an Acid Spirit, and as I remember an Alcalizate Solution, and found not any of those various Liquors to destroy its Shining property.
41 XVI. Having found by this Observation, that a warm Liquor would not extinguish Light in the Diamond, I thought fit to try, whether by reason of its warmth it would not excite it, and divers times I found, that if it were kept therein, till the Water had leisure to communicate some of its Heat to it, it would often shine as soon as it was taken out, and probably we should have seen it Shine more, whilst it was in the Water, if some degree of Opacity which heated Water is wont to acquire, upon the score of the Numerous little Bubbles generated in it, had not kept us from discerning the Lustre of the Stone.
42 I after bethought my self of imploying a way, which produc'd the desir'd Effect both sooner and better. For holding betwixt my Fingers a Steel Bodkin, near the Lower part of it, I press'd the point hard against the Surface of the Diamond, and much more if I struck the point against it, the Coruscation would be extremely suddain, and very Vivid, though very Vanishing too, and this way which commonly much surpris'd and pleas'd the Spectators, seem'd far more proper than the other, to show that pressure alone, if forcible enough, though it were so suddain, and short, that it could not well be suppos'd to give the Stone any thing near a sensible degree of Warmth, as may be suspected of Rubbing, yet 'tis sufficient to generate a very Vivid Light.
43 We afterwards, try'd precious Stones, as Diamonds, Rubies, Saphires, and Emeralls, &c. but found not any of them to Shine except some Diamonds, and of these we were not upon so little practice, able to fore-tell before hand, which would be brought to Shine, and which would not; For several very good Diamonds, either would not Shine at all, or much less than others that were farr inferiour to them. And yet those Ingenious Men are mistaken, that think a Diamond must be foul and cloudy, as Mr. Claytons was, to be fit for Shining; for as we could bring some such to afford a Glimmering Light, so with some clear and excellent Diamonds, we could do the like. But none of those many that we try'd of all Kinds, were equal to the Diamond on which the Observations were made, not only considering the degree of Light it afforded, but the easiness wherewith it was excited, and the Comparatively great duration of its Shining.