Page:Cyclopaedia, Chambers - Volume 1.djvu/919

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GOL

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GOL

Mr. Boyte made a Menflruum of Butter of Antimony, which diffolved Gold with great Facility ; and hence con- cluded that Gold might be diffolv'd without Sea Salt : But by Mi (lake, the effective Part even of this Menflruum be- ing {till Sea Salt, which is an Ingredient in Sublimate of Mer- cury wherewith Butter of Antimony is made. See Salt, Sublimate, &c.

The feventh Character is that it readily and fpontaneoufly, as by Tome Magnetic Virtue, attracts, and abforbs Mercury ; tho' what My Lord "Bacon writes, viz. that Gold, in imbib- ing Mercury, increafes in Weight, we doubt, is but ill war- ranted. For 'tis certain it rauft be increas'd in Bulk, more than in Weight, and confequenrly muft be fpeciflca-lly lighter. See Mercup.y.

It may be added, that as foon as the Mercury enters the Gold, the Metal becomes foft, like a Pafte. See Amalga- mation.

The eighth Character is, that it withftands the Violence both of Lead, and Antimony, /. e. being fufed in the Coppel along with either of thofe Matters, it does not diffipateand fly off with them inFume, but remains fix'd, and unchanged. All other Metals, except Gold, and Silver melted with Lead, perifh. with it, and evaporate by Fire ; and in Anti- mony, all other Metals except Gold, and even Silver itfelf, un- dergo the fame Fate. — Thus, if a Mafs confifting of Gold, Silver, Stones, Copper, £5c. be fufed together with Antimo- ny, the feveral Matters become feparated, and all but the Gold riles to the Surface in form of a Scoria, and is blown off with Bellows: But the Gold remains behind, much puri- fied, as having loft all its heterogeneous Parts along with the other Metals. And hence Antimony is ufed as the Teft of Gold. See Test, Coptkl, Refining, &c.

The ninth Character is that of all Bodies it is the fim- pleft ( the primary Elements being here excepted ).■ — By jimple we here mean that whofe minuteft Part has all the Phyfical Properties of the whole Mafs. Thus, if a Grain of Gold be diffolv'd in Aqua Regia-^ and a fingle Drop of the Solution be taken, a Quantity of Gold may be feparated therefrom, which fhall only be the Millionth Part of the Grain, and yet have all the Characters of Gold. Or, if you ■fufc a Grain of Gold with a large Mafs of Silver, and mix the two together, fo that thcGold becomes equally diffufed thro' the whole Mafs; you will havein every Particle of the Mafs a Particle of perfect Gold. Accordingly, diffolve any Part of the Mixture in Aqua fords, and a Quantity of Gold will precipitate to the Bottom, bearing the fame Propor- tion to the Grain that the Part diffolved did to the whole Mafs. On which Principle depends the Art of Effayng. See Essaync.

AH the known Parts of the Earth afford this precious Metal; tho' with a deal of Difference, in point of Purity, and Abundance : Europe, fo fertile in other relpects, comes Jhort of all the other Quarters, in Gold. America furnilhes themoft; and particularly the Mines of Tern, and Chilly. That of Afia is etteem'd thefineit, particularly that of Me- naricabo in the Eaji Indies : The Spaniards affure us that they get Gold out of fome of their Peruvian Mines, 25 Ca- rats fine before it be purified. Add, that thcGold of Axi- ma on the Coafl: of Africa is found from 22 to 25 Carats.

Glauber, an eminent Chymiff, holds that there is not any Sand, or Stone, but Gold may be procured from ; Lime- ftone only excepted : Only that the Expence of feparating it, much furmounts the Profits.

Gold is chiefly found in Mines : Tho' there is fome alfo found in the Sand and Mud of Rivers, and Torrents ; par- ticularly in Guinea. This laff. is in form of a fine Powder, and call'd dfj.y.oxpv<r@-, Gold-dujl. Glauber holds that there is a third fort of Gold, fcarce found any where but in the Drains of the Mountains of Chilly, which they feparate from 'the Earth by warning ; whence the Places where it is found, or feparated, are call'd Lavaderos.

This Earth is ufually reddifh, and very fine : At about fix Foot deep it is mix'd with Grains of large FJuff; and from hence commences the Stratum, or Bed 0$ Gold. Between are Banks of ioft blueifh Stone, mix'd with yellow Threads, which yet are not Gold, but only Pyrites, or Marcaffites of Gold.

When they have difcover'd any of this Earth, they en- deavour to bring Rivulets to it (which in thofe Mountains arc very frequent) in order, by force thereof, to tear off the upper Earth, and lay the Golden Stratum bare. This they forward by digging with Spades, &c. As foon as the Golden Earth is uncover'd, they turn off the Water; and dig up the Soil by Force of Arm 5 and loading it on Mules, carry it "to the Lavedoro's, i. e. a fort of Bafons of Water, where the Earth undergoing divers repeated Lotions, in different Waters, the earthy, and impure Part is all feparated and carried off by the Stream, andtheGijW left at Bottom. See Lavatory.

This Method of getting Gold is immenfely gainful ; the Expences being but trifling, compared with thofe accruing in the common way by Machines, Fire, and Quickfilver;

The richer* of thefe Zavadero's is that de VFfiancia del Key, tweive Leagues from the Conception, a Port of the South St3.~Thurwgia, and fome other Places along the Rhine, are the only Places in Europe, where Gold is got in this manner.

The Gold of Mines is of two kinds; the one in final! Pieces, or Grains of various Forms, and Weights. Of this fort, among the Specimens fent by Columbus into Spain, to let them fee the Richnefs of his Difcovery, there were fome of 18 Ounces Weight ; and the Relations of thofe Days af- fure us, that in 1502 there were others found of thirty two Pounds Weight.

The other kind of Gold is dug up in Stony Glebes, whicK is what they call the Mineral, or Ore of Gold: Thefe Glebes are of various Colours, and ufually 1 50 or 160 Fathom deep. Along with the Gold they ufually contain fome other Mineral Matter, as Antimony, Vitriol, Sulphur, Copper, or Silver 5 particularly the laft; without fome Share of which it is fcarce ever found.

Manner of feparating Gold.

They firft break the Metalline Stone with Iron Mallets; pretty fmall ; then carry it to the Mills, where it is ground into a very fine Powder ; and luftly pafs it thro' feveral Brafs Sieves one after another, thelaft as fine as any of our Silk Sieves.

The Powder thus prepared, is laid in wooden Troughs with a proper Quantity of Mercury and Water, and there left to knead and fatururein the Sun and Air for twice twenty four Hours. After this the Water, with the recrememi- tious Earth is drove out of the Tubs by means of other hot Waters, pour'd thereon. This dnne, there remains no- thing but a Mkfs of Mercury with all the Gold that was in the Ore. The Mercury they feparate from it by Dillilla- tion in large Alembicks. The Gold, in this State, is call'd Virgin Gold ; as well as that found in the Sand of Rivers, or that in Grains in the Mines; in regard none of them have pafs'd the Fire. After this, they ufually fufe them in Cruci- bles, and carl them into Plates, or Ingots. See Fusion.

Manner of Refining Gold.

There are three principal Manners of refining Gold ; the firft with Antimony; the fecond with Sublimate; and the third with Aqua fortis. This lafl, which is call'd depart- ing, or Parting, is already defcrib'd under the Article De- part ; and the two former under thofe of Refining. See Refining.

Befide thefe three, there are other Methods of Refining Gold ; particularly that call'd ihe Coppel, which is performed with Lead and Afhes ; and that call'd Cement atioit, by means of a Compofirion of Brick Duff, common Salt, Sal Ammoniac, Sal Gemma, and Urine. See Coppel, and Cementation.

'The Ejfaying of Gold, is performed with the Touch- {tone, but more fecurely by Fire. See Touch- Stone, and Essaying.

For the Making of Gold, fee c Philofopher Stone, and Transmutation.

GoldWire, is a Cylindrical Ingot of Silver,fuperficially gilt, or cover'd with Gold, at the Fire- ; and afterwards drawn Vuc- ceffively thro' an infinite Number of. little round Holes of a Wire-drawing Iron, each lefs than the other, till it be no bigger than a Hair of the Head. See Wire.

It may be obferv'd, that before the Wire be redue'd to this exceffive Finenefs, it is drawn thro' above an hundred and forty different Holes ; and that each time they draw it; it is rubb'd frefh over with new Wax, both to facilitate its Paffage, and to prevent the Silver's appearing thro'.

It is amazing to what Degree of Finenefs the Gold is here drawn; and yet it itill keeps firm together, and never mews the leafl Signs of the Silver underneath it. The Reader may fee a Computation hereof, as alfo a more particular Account of the manner of proceeding, under the Article Ductility of Gold.

GoldWire flatted, is th& formerWire flatted between two Rollers of polihYd Steel, to fit it to be fpun on Silk, or to be ufed flat as it is, without fpinning, in certain Stuffs, Laces, Embroideries, $£>c.

GoLDTHREADjOr^mGoLD, is the flatted Gold wrapp'd, . or laid over a Thread of Silk, by twitting it with a Wheel, and Iron Bobins.

The Methods of managing and drawing Gold and Silver both real and feeming in all thefe Kinds, are very curious, and of great Ufe in Commerce.

Manner of forming Gold Wire, and Gold Thread both round, and flat.

First, An Ingot of Silver of 24 Pound is forged into a Cylinder about an Inch in Diameter: Then 'tis drawn thro' eight or ten Holes of a large, coarse Drawing Iron, both to finish the

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