Experiment XLVIII
The third chief ſort of the Adventitious Colours of Metals, is, that which is produc’d by aſſociating them (eſpecially when Calcin’d) with other fuſible Bodies, and Principally Venice, and other fine Glaſs devoid of Colour.
I have formerly given you an Example, whereby it may appear, that a Metal may impart to Glaſs a Colour much differing from its own, when I told you, how with Silver, I had given Glaſs a lovely Golden Colour. And I ſhall now add, that I have Learn’d from one of the Chief Artificers that ſells Painted Glaſs, that thoſe of his Trade Colour it Yellow with a preparation of the Calx of Silver. Though having lately had occaſion among other Tryals to mingle a few grains of Shell-ſilver (ſuch as is imploy’d with the Penſil and Pen) with a convenient proportion of powder’d Cryſtal Glaſs, having kept them two or three hours in fuſion, I was ſurpriz’d to find the Colliquated Maſs to appear upon breaking the Crucible of a lovely Saphirine Blew, which made me ſuſpect my Servant might have brought me a wrong Crucible, but he conſtantly affirm’d it to be the ſame wherein the Silver was put, and conſiderable Circumſtances countenanc’d his Aſſertion, ſo that till I have opportunity to make farther Tryal, I cannot but ſuſpect, either that Silver which is not (which is not very probable) brought to a perfect Fuſion and Colliquation with Glaſs, may impart to it other Colours than when Neal’d upon it, or elſe (which is leſs unlikely) that though Silver Beaters uſually chuſe the fineſt Coyn they can get, as that which is moſt extenſive under the Hammer, yet the Silver-leaves of which this Shel-ſilver was made, might retain ſo much Copper as to enable it to give the predominant tincture to the Glaſs.
For, I muſt proceed to tell you (Pyrophilus) as another inſtance of the Adventitious Colours of Metals, that which is ſomething ſtrange, Namely, That though Copper Calcin’d per ſe affords but a Dark and baſely Colour’d Calx, yet the Glaſsmen do with it, as themſelves inform me, Tinge their Glaſs green. And I remember, that when once we took ſome crude Copper, and by frequent Ignition quenching it in Water had reduc’d it to a Dark and Ill-colour’d Powder, and afterward kept it in Fuſion in about a 100. times its weight of fine Glaſs, we had, though not a Green, yet a Blew colour’d Maſs, which would perhaps have been Green, if we had hit right upon the Proportion of the Materials, and the Degree of Fire, and the Time wherein it ought to be kept in Fuſion, ſo plentifully does that Metal abound in a Venerial Tincture, as Artiſts call it, and in ſo many wayes does it diſcloſe that Richneſs. But though Copper do as we have ſaid give ſomewhat near the like Colour to Glaſs, which it does to Aqua-fortis, yet it ſeems worth inquiry, whether thoſe new Colours which Mineral Bodies diſcloſe in melted Glaſs, proceed from the Coalition of the Corpuſcles of the Mineral with the Particles of the Glaſs as ſuch, or from the Action (excited or actuated by fire) of the Alcalizate Salt (which is a main Ingredient of Glaſs,) upon the Mineral Body, or from the concurrence of both theſe Cauſes, or elſe from any other. But to return to that which we were ſaying, we may obſerve that Putty made by calcining together a proportion of Tin and Lead, as it is it ſelf a White Calx, ſo does it turn the Pitta di Cryſtallo (as the Glaſsmen call the matter of the Purer ſort of Glaſs, wherewith it is Colliquated into a White Maſs, which if it be opacous enough is employ’d, as we elſewhere declare, for White Amel. But of the Colours which the other Metals may be made to produce in Colourleſs Glaſs, and other Vitrifiable Bodies, that have native Colours of their own, I muſt leave you to inform your ſelf upon Tryal, or at leaſt muſt forbear to do it till another time, conſidering how many Annotations are to follow, upon what has in this and the two former Experiments been ſaid already.
Annotation I.
When the Materials of Glaſs being melted with Calcin’d Tin, have compos’d a Maſs Undiaphanous and White, this White Amel is as it were the Baſis of all thoſe fine Concretes that Goldſmiths and ſeveral Artificers imploy in the curious Art of Enamelling. For this White and Fuſible ſubſtance will receive into it ſelf, without ſpoyling them, the Colours of divers other Mineral ſubſtances, which like it will indure the fire.
Annotation II.
So that as by the preſent (XLVIII.) Experiment it appears, that divers Minerals will impart to fuſible Maſſes, Colours differing from their own; ſo by the making and compounding of Amels, it may appear, that divers Bodies will both retain their Colour in the fire, and impart the ſame to ſome others wherewith they were vitrifi’d, and in ſuch Tryals as that mention’d in the 17. Experiment, where I told you, that ev’n in Amels a Blew and Yellow will compound a Green. ’Tis pretty to behold, not only that ſome Colours are of ſo fix’d a Nature, as to be capable of mixture without receiving any detriment by the fire, that do’s ſo eaſily deſtroy or ſpoyl thoſe of other Bodies; but Mineral Pigments may be mingled by fire little leſs regularly and ſucceſsfully, than in ordinary Dyeing Fatts, the vulgar Colours are wont to be mingled by the help of Water.
Annotation III.
’Tis not only Metalline, but other Mineral Bodies, that may be imploy’d, to give Tinctures unto Glaſs (and ’tis worth noting how ſmall a quantity of ſome Mineral ſubſtances, will Tinge a Comparatively vaſt proportion of Glaſs, and we have ſometimes attempted to Colour Glaſs, ev’n with Pretious Stones, and had cauſe to think the Experiment not caſt away. And ’tis known by them that have look’d into the Art of Glaſs, that the Artificers uſe to tinge their Glaſs Blew, with that Dark Mineral Zaffora, (ſome of my Tryals on which I elſewhere acquaint you) which ſome would have to be a Mineral Earth, others a Stone, and others neither the one, nor the other, but which is confeſſedly of a Dark, but not a Blew Colour, though it be not agreed of what particular Colour it is. ’Tis likewiſe though a familiar yet a remarkable practiſe among thoſe that Deal in the making of Glaſs, to imploy (as ſome of themſelves have inform’d me) what they call Manganeſs, and ſome Authors call Magneſia (of which I make particular mention in another Treatiſe) to exhibit in Glaſs not only other Colours than its own, (which is ſo like in Darkneſs or blackiſhneſs to the Load ſtone, that ’tis given by Mineraliſts, for one of the Reaſons of its Latine Name) but Colours differing from one another. For though they uſe it, (which is ſomewhat ſtrange) to Clarifye their Glaſs, and free it from that Blewiſh Greeniſh Colour, which elſe it would too often be ſubject to, yet they alſo imploy it in certain proportions, to tinge their Glaſs both with a Red colour, and with a Purpliſh or Murry, and putting in a greater Quantity, they alſo make with it that deep obſcure Glaſs which is wont to paſs for Black, which agrees very well with, and may ſerve to confirm what we noted near the beginning of the 44th Experiment, of the ſeeming Blackneſs of thoſe Bodies that are overcharg’d with the Corpuſcles of ſuch Colours, as Red, or Blew, or Green, &c. And as by ſeveral Metals and other Minerals we can give various Colours to Glaſs, ſo on the other ſide, by the differing Colours that Mineral Oars, or other Mineral Powders being melted with Glaſs diſcloſe in it, a good Conjecture may be oftentimes made of the Metall or known Mineral, that the Oar propos’d, either holds, or is moſt of kin to. And this eaſie way of examining Oars, may be in ſome caſes of good uſe, and is not ill deliver’d by Glauber, to whom I ſhall at preſent refer you, for a more particular account of it: unleſs your Curioſity command alſo what I have obſerv’d about theſe matters; only I muſt here advertiſe you, that great circumſpection is requiſite to keep this way from proving fallacious, upon the account of the variations of Colour that may be produc’d by the differing proportions that may be us’d betwixt the Oar and the Glaſs, by the Richneſs or Poorneſs of the Oar it ſelf, by the Degree of Fire, and (eſpecially) by the Length of Time, during which the matter is kept in fuſion; as you will eaſily gather from what you will quickly meet with in the following Annotation upon this preſent 48th Experiment.
Annotation IV.
There is another way and differing enough from thoſe already mention’d, by which Metalls may be brought to exhibit adventitious Colours: For by This, the Metall do’s not ſo much impart a Colour to another Body, as receive a Colour from it, or rather both Bodies do by the new Texture reſulting from their miſtion produce a new Colour. I will not inſiſt to this purpoſe upon the Examples afforded us by yellow Orpiment, and common Sea Salt, from which, ſublim’d together, Chymiſts unanimouſly affirm their White or Cryſtalline Arſenick to be made: But ’tis not unworthy our noting, That though Yellow Orpiment be acknowledg’d to be the Copiouſeſt by far of the two Ingredients of Arſenick, yet this laſt nam’d Body being duely added to the higheſt Colour’d Metall Copper, when ’tis in fuſion, gives it a whiteneſs both within and without. Thus Lapis Calaminaris changes and improves the Colour of Copper by turning it into Braſs. And I have ſometimes by the help of Zinck duely mix’d after a certain manner, given Copper one of the Richeſt Golden Colours that ever I have ſeen the Beſt true Gold Ennobled with. But pray have a care that ſuch Hints fall not into any hands that may mis-imploy them.
Annotation V.
Upon the Knowledge of the differing wayes of making Minerals and Metalls produce their adventitious Colours in Bodies capable of Vitrification, depends the pretty Art of making what Chymiſts by a Barbarous Word are pleas’d to call Amanſes, that is counterfeit, or factitious Gemms, as Emeralds, Rubies, Saphires, Topazes, and the like. For in the making of theſe, though pure Sand or Calcin’d Cryſtal give the Body, yet ’tis for the moſt part ſome Metalline or Mineral Calx, mingled in a small proportion that gives the Colour. But though I have many years ſince taken delight, to divert my ſelf with this pleaſing Art, and have ſeen very pretty Productions of it, yet beſides that I fear I have now forgot moſt of the little Skill I had in it, this is no place to entertain you with what would rather take up an intire Diſcourſe, than be comprehended in an Annotation; wherefore the few things which I ſhall here take notice of to you, are only what belong to the preſent Argument, Namely,
Firſt, That I have often obſerv’d that Calcin’d Lead Colliquated with fine White Sand or Cryſtal, reduc’d by ignitions and ſubſequent extinctions in Water to a ſubtile Powder, will of it ſelf be brought by a due Decoction to give a cleer Maſs Colour’d like a German Amethyſt. For though this glaſs of Lead, is look’d upon by them that know no better way of making Amanſes, as the grand Work of them all, yet which is an inconvenience that much blemiſhes this way, the Calcin’d Lead it ſelf does not only afford matter to the Amanſes, but has alſo as well as other Metals a Colour of its own, which as I was ſaying, I have often found to be like that of German (as many call them) not Eaſtern Amethyſts.
Secondly, That nevertheleſs this Colour may be eaſily over-powr’d by thoſe of divers other Mineral Pigments (if I may ſo call them) ſo that with a glaſs of Lead, you may Emulate (for Inſtance) the freſh and lovely Greenneſs of an Emerald, though in divers caſes the Colour which the Lead it ſelf upon Vitrification tends to, may vitiate that of the Pigment, which you would introduce into the Maſs.
Thirdly, That ſo much ev’n theſe Colours depend upon Texture, that in the Glaſs of Lead it ſelf made of about three parts of Lytharge or Minium Colliquated with one of very finely Powder’d Cryſtal or Sand, we have taken pleaſure to make the mixture paſs through differing Colours, as we kept it more or leſs in the Fuſion. For it was not uſually till after a pretty long Decoction that the Maſs attain’d to the Amethyſtin Colour.
Fourthly and laſtly, That the degrees of Coction and other Circumſtances may ſo vary the Colour produc’d in the ſame maſs, that in a Crucible that was not great I have had fragments of the ſame Maſs, in ſome of which perhaps not ſo big as a Hazel-Nut, you may diſcern four diſtinct Colours.
Annotation VI.
You may remember (Pyrophilus) that when I mention’d the three ſorts of adventitious Colours of Metals, I mention’d them but as the chief, not the only. For there may be other wayes, which though they do not in ſo ſtrict a ſenſe belong to the adventitious Colours of Metals, may not inconveniently be reduc’d to them. And of theſe I ſhall name now a couple, without denying that there may be more.
The firſt may be drawn from the practiſe of thoſe that Dye Scarlet. For the famouſeſt Maſter in that Art, either in England or Holland, has confeſs’d to me, that neither others, nor he can ſtrike that lovely Colour which is now wont to be call’d the Bow-Dye, without their Materials be Boyl’d in Veſſels, either made of, or lin’d with a particular Metall. But of what I have known attempted in this kind, I muſt not as yet for fear of prejudicing or diſpleaſing others give you any particular Account.24
The other way (Pyrophilus) of making Metals afford unobvious Colours, is by imbuing divers Bodies with Solutions of them made in their proper Menſtruum’s, As (for Inſtance) though Copper plentifully diſſolv’d in Aqua fortis, will imbue ſeveral Bodies with the Colour of the Solution; Yet Some other Metalls will not (as I elſewhere tell you) and have often try’d. Gold diſſolv’d in Aqua Regia, will, (which is not commonly known) Dye the Nails and Skin, and Hafts of Knives, and other things made of Ivory, not with a Golden, but a Purple Colour, which though it manifeſt it ſelf but ſlowly, is very durable, and ſcarce ever to be waſh’d out. And if I miſremember not, I have already told you in this Treatiſe, that the purer Cryſtals of fine Silver made with Aqua fortis, though they appear White, will preſently Dye the Skin and Nails, with a Black, or at leaſt a very Dark Colour, which Water will not waſh off, as it will ordinary Ink from the ſame parts. And divers other Bodies may the Same way be Dy’d, ſome of a Black, and others of a Blackiſh Colour.
And as Metalline, ſo likewiſe Mineral Solutions may produce Colours differing enough from thoſe of the Liquors themſelves. I ſhall not fetch an Example of this, from what we daily ſee happen in the powdring of Beef, which by the Brine imploy’d about it (eſpecially if the fleſh be over ſalted) do’s oftentimes appear at our Tables of a Green, and ſometimes of a Reddiſh Colour, (deep enough) nor ſhall I inſiſt on the practiſe of ſome that deal in Salt Petre, who, (as I ſuſpected, and as themſelves acknowledg’d to me) do, with the mixture of a certain proportion of that; and common Salt, give a fine Redneſs, not only to Neats Tongues, but which is more pretty as well as difficult, to ſuch fleſh, as would otherwiſe be purely White; Theſe Examples, I ſay, I ſhall decline inſiſting on, as chuſing rather to tell you, that I have ſeveral times try’d, that a Solution of the Sulphur of Vitriol, or ev’n of common Sulphur, though the Liquor appear’d clear enough, would immediately tinge a piece of new Coin, or other clean Silver, ſometimes with a Golden, ſometimes with a deeper, and more Reddiſh colour, according to the ſtrength of the Solution, and the quantity of it, that chanc’d to adhere to the Metall; which may take off your wonder that the water of the hot Spring at Bath, abounding with diſſolv’d Subſtances of a very Sulphureous Nature, ſhould for a while, as it were gild, the new or clean pieces of Silver coyn, that are for a due time immers’d in it. And to theſe may be added thoſe formerly mention’d Examples of the adventitious Colours of Mineral Bodies; which brings into my mind, that, ev’n Vegetable Liquors, whether by degeneration, or by altering the Texture of the Body that imbibes them, may ſtain other Bodies with Colours differing enough, from their own, of which very good Herbariſts have afforded us a notable Example, by affirming that the Juice of Alcanna being green (in which ſtate I could never here procure it) do’s yet Dye the Skin and Nails of a Laſting Red. But I ſee this Treatiſe is like to prove too bulky without the addition of further Inſtances of this Nature.