EXPERIMENT VIII.
There is an Experiment, Pyrophilus, which though I do not ſo exactly remember, and though it be ſomewhat Nice to make, yet I am willing to Acquaint You with, becauſe the thing Produc'd, though it be but a Curioſity, is wont not a little to pleaſe the Beholders, and it is a way of turning by the help of a Dry Subſtance, an almoſt Golden-Colour'd Concrete, into a White one, the Several Tryals are not at preſent ſo freſh in my Memory to enable me to tell you Certainly, whether an Equal onely or a Double weight of Common Sublimate muſt be taken in reference to the Tinglaſs, but if I miſtake not, there was in the Experiment that ſucceeded beſt, Two parts of the Former taken to One of the Latter. Theſe Ingredients being finely Powdred and Exactly mix'd, we Sublim'd together by degrees of fire (the due Gradation of which is in this Experiment a thing of main Importance) there aſcended a matter of a very peculiar Texture, for it was for the moſt part made up of very Thin, Smooth, Soft and Slippery Plates, almoſt like the fineſt ſort of the Scales of Fiſhes, but of ſo Lovely a White Inclining to
Pearl-Colour, and of ſo Curious and Shining a Gloſs, that they appear'd in ſome reſpect little Inferiour to Orient Pearls, and in other Regards, they ſeem'd to Surpaſs them, and were Applauded for a ſort of the Prettieſt Trifles that we had ever prepar'd to Amuſe the Eye. I will not undertake that though you'l hardly miſs changing the Colour of your ſhining Tinglaſs, yet you will the firſt or perhaps the ſecond time hit Right upon the way of making the Gliſtring Sublimate I have been mentioning.
EXPERIMENT IX.
When we Diſſolve in Aqua Fortis a mixture of Gold and Silver melted into one Lump, it uſually happens that the Powder of Gold that falls to the bottom, as not being Diſſoluble by that Menſtruum, will not have its own Yellow, but appear of a Black Colour, though neither the Gold, nor the Silver, nor the Aqua Fortis did before manifeſt any Blackneſs. And divers Alchymiſts, when they make Solutions of Minerals they would Examine, are very Glad, if they ſee a Black Powder Præcipitated to the Bottom, taking it for a Hopefull Sign, that thoſe Particles are of a Golden Nature,
which appear in a Colour ſo ordinary to Gold parted from other Metalls by Aqua Fortis, that it is a trouble to the Refiner to Reduce the Præcipitated Calx to its Native Colour. For though, (as we have try'd,) that may be Quickly enough done by Fire, which will make this Gold look very Gloriouſly (as indeed 'tis at leaſt one of the Beſt wayes that is Practis'd for the Refining of Gold,) yet it requires both Watchfulneſs and Skill, to give it ſuch a Degree of Fire as will ſerve to Reſtore it to its Luſtre, without giving it ſuch a One, as may bring it to Fuſion, to which the Minuteneſs of the Corpuſeles it conſiſts of makes the Powder very apt. And this brings into my Mind, that having taken a Flat and Bright piece of Gold, that was Refin'd by a Curious and Skilfull Perſon on purpoſe to Trye to what height of Purity Gold could be brought by Art, I found that this very piece, as Glorious as it look'd, being rubb'd a little upon a piece of fine clean Linnen, did ſully it with a kind of Black; and the like I have obſerv'd in Refin'd Silver, which I therefore mention, becauſe I formerly ſuſpected that the Impurity of the Metall might have been the only Cauſe of what I have divers times obferv'd in wearing Silver-hilted Swords, Namely, that
where they rubb'd upon my Clothes, if they were of a Light-Colour'd Cloath, the Affriction would quickly Black them; and Congruouſly hereunto I have found Pens Blackt almoſt all over, when I had a while carri'd them about me in a Silver Ink-caſe. To which I ſhall only add, that whereas in theſe ſeveral Inſtances of Denigration, the Metalls are worn off, or otherwiſe Reduc'd into very Minute Parts, that Circumſtance may prove not Unworthy your Notice.
EXPERIMENT X.
That a Solution of Silver does Dye Hair of a Black Colour, is a Known Experiment, which ſome perſons more Curious than Dextrous, have ſo Unluckily made upon themſelves as to make their Friends very Merry. And I remember that the other day, I made my ſelf ſome Sport by an Improvement of this Obſervation, for having diſſolv'd ſome Pure Silver in Aqua Fortis, and Evaporated the Menſtruum ad ſiccitatem, as they ſpeak, I caus'd a Quantity of fair Water to be pour'd upon the Calx two or three ſeveral times, and to be at each Evaporated, till the Calx was very Drye, and all the Greeniſh Blewneſs that is wont to appear in Common Cryſtals of Silver,
was quite carry'd away. Then I made thoſe I meant to Deceive, Moiſten ſome part of their Skin with their own Spittle, and ſlightly Rub the moiſtned parts with a little of this Prepar'd Silver, Whereupon they Admir'd to ſee, that a Snow-white Body laid upon the White Skin ſhould preſently produce a deep Blackneſs, as if the ſtains had been made with Ink, eſpecially conſidering that this Blackneſs could not, like that produc'd by ordinary Ink, be readily Waſh'd off, but requir'd many Hours, and part of it ſome dayes to its Obliteration. And with the ſame White Calx and a little Fair Water we likewiſe Stain'd the White Hafts of Knives, with a laſting Black in thoſe parts where the Calx was Plentifully enough laid on, for where it was laid on but very Thinly, the Stain was not quite of ſo Deep a Colour.