Page:Cyclopaedia, Chambers - Volume 1.djvu/920

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GOL

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GOL

Roundnefs, and to reduce it to about three Fourths of its former Diameter. This done, they file it very carefully all over, to take off any Filth remaining of the Forge: Then they cut it in the Middle, and thus make two equal Ingots there- of; each about id Inches long 5 which they draw thro' fe- veral new Holes to take off any Inequalities the File may have left, and to render it as fmooth, and equable as poi- fible.

The Ingot thus far prepar'd, they heat it in a Coal Fire : Then, talcing fomc-Gold Leaves, each of about four Inches fquare, and weighing 12 Grains; they join four, eight, twelve, or fixteen of thefc together, as the Wire is intended to be more, or lefs gilt ; and when they are fo join'd as only to form a fingle Leaf, they rub the Ingots, reeking hot, with a Burnifher.

Thefe Leaves, thus prepar'd, they apply over the whole Surface of the Ingot to the Number of fix, over each other; burnifhing or rubbing them well down with theBlood-flonc, to clofe, and fmoothen them.

When gilt, the Ingots are laid a-new in a Coal Fire; and when rais'd to a certain Degree of Heat, they go over them a fecond time with the Blood-ftone, both to folder the Gold more perfectly, and to finifli the Polifhing

The Gilding finifh'd, it remains to draw the Ingot into Wire. In order to this, they pafs it thro' twenty Holes of a moderate Drawing-iron, by which it is brought to the Thickneft of the Tag of a Lace : From this time, the Ingot lofes its Name, and commences Gold Wire. Twenty Holes more of a leffer Iron, leave it fmall enough for the leaitlron ; the fined Holes of*which laft, fcareo exceeding a Hair of the Head, finifh the Work.

To difpofe the Wire to be fpun on Silk, they pafs it be- tween two Rollers of a little Mill: Thefe Rollers are of po- lifh'd Steel, and about three Inches Diameter. They arc fet very clofe to each other, and turn'd by means of a Han- dle faften'd to one of them, which gives Motion to the other. The Gold Wire in paffing between the two, is render'd quite flat; but without lofing any thing of its Gilding ; and is render'd fo exceedingly thin, and flexible, that it is eafily fpun on Silk Thread, by means of a Hand Wheel ; and fo wound on a Spool, or Bobin. See Flexibility.

Gold Leaf, or Beaten Gold, is Gold beaten with a Hammer, into exceedingly thin Leaves.

Tis prodigious to confidcr the Fincnefs they will thus re- duce a Body otGold to : 'Tis computed, that an Ounce may be beaten into 1 tfoo Leaves, each three Inches fquare; in which State, it takes up more 159092 times its former Space. See Ductility.

This Gold they beat on a Block of Marble, commonly black Marble, about a Foot fquare, and ufual rais'd three Foot high : They make ufe of three forts of Hammers, form'd like Mallets, of polifh'd Iron. The firft, which weighs three, or four Pounds, ferves to chafe, or drive; the fecond, of eleven or twelve Pounds, to clofe; and the third, which weighs fourteen or fifteen Pounds, to ft retch, and finifli.

They alfo make ufe of four Moulds, of different Sizes; viz. two of Vellum, the fmalleft whereof confifts of 40 or 50 Leaves, and the larger, of two hundred : The other two, con- futing each of 500 Leaves, are made of Bullocks Gut, well fcour'd and prepared. See Mould.

The Method of freparfag, mid heating Gold, is as follows.

They firft melt a Quantity of pure Gold, and form it into an Ingot : This they reduce, by forging, into a Plate about the Thicknefs of a Sheet of Paper : Which done, they cut the Plate into little Pieces about an Inch fquare, and lay them in the firfl, or fmallelt Mould, to begin to firetch them. After they have been hammer'd here a while with the fmal- left Hammer, they cut each of them into four; and put them in the fecond Mould to be extended further.

Upon taking them hence, they cut them again into four, and put them into the third Mouid ; out of which they are taken, divided into four, as before, and laid in the laft, or finifhing Mould ; where they are beaten to the Degree of Thinnefs required. — ■

The Leaves thus finifh'd, they take them out of the Mould, and difpofe them in little Paper Books prepar'd with red Bole, for the Gold to flick to : Each Book ordinarily contains 25 Gold Leaves.

There are two Sizes of thefe Books : Twenty five Leaves of the fmalleft only weigh five or fix Grains; and the fame Number of the largeft nine, or ten Grains.

It mult be obferv'd that Gold is beaten more, or lefs, ac- cording to the Kind, or Quality of the Work it is intended for : That for the Gold-wire Drawers to gild their Ingots withal, is left much thicker, than that for gilding the Frames of Pictures, &c. withal.

Shell Gold is that us'd by the Illuminers; and where- withal! v. <; write Gold Letters. — It is made of the Parings of Leaf Gold, and even of the Leaves themfelves, redue'd into an impalpable Powder, by grinding on a Marble, with Ho-

ney. After leaving it to infufe fome time in Aqua fort is, they put it in Shells, where it flicks. To ufe it, they dilute it with Gum Water, or Soap Water.

Bumifh'd Gold, is that fmoorhen'd, or polifh'd with a Steel Inflrument, calfd the Surnijher, if it b« wrought Gold., or Gilding on Metal ; or with a Wolf's Tooth, if it be gilding in Water. See Burnisher., and Gilding.

Million o/'Gold, is a Phrafe us'd to iignify a Million of Crowns. See Crowns.

Tun of Gold, is a kind of Money of Account, us'd by the 2)utcb t and in lome other Countries; containing a hundred thoufand Florins. See Florin.

Gold Coin, or Species g/*Gold ; fee Coin.

A hundred Pounds cf, or in, Gold, is found to weigh two Pound, ten Ounces : The fame Sum in Silver, weighs 26' Pound, 4 Ounces. Twenty two Pence, in Copper Farthings and Half-pence, weigh one Pound Avoirdunoile. —

A Tun of Gold at 4 Pounds the Ounce amounts to ofibco/. A Tun of Silver at 5 5. 2 d. the Ounce, to 6200 /. A Pound Sterling Gold, to 48 /. An Ounce is worth 4 /. The Penny, weight, 4 s. One Grain, 2 d. A Pound of Sterling Silver amounts to 3 /. 2 s. An Ounce is worth 5 s, 2 d. The Penny- weight, 3 d. andiomethjng more ; one Grain, a half-penny. A Pound of Silver Avoirdupoife comes to 3 /. 5 s. 3 d. half- penny.

Mofaic Gold, is Gold applied in Panels on a proper Ground, diflributed into Squares, Lozanges, and other Com- partments, part whereof is fhadow'd to raife, or heighten the reft. See Mosaic.

Virgin Gold, is Gold, juft as it is caken out of the Mines before it have undergone any Aclion, or Preparation of Fire : Whence the Greeks call it £irvfa. Such is the alf4fis%? tfa©-., or Gold fDt/Jl, and that got by Lotion in the Lavedero's in Chilly: 'Tis added, that there are Maffes, or Lumps of pure Gold found in the Mines, particularly thofe nf Hungary. Ac- cordingly, in the Emperor's Collection arc fiill preserved feveral Plates ofGold, faid to have been thus found.

Virgin Gold is faid to be very pale, and fo foft that it may- be moulded into any Figure, with the Hand : It even takes an Impremon from a Seal, like the loftcft Wax. To harden it, as alio to highten its Colour, they mix Emery with it.

Fine, or Fure Gold, is that purged by Fire of all its Im- purities, and all Alloy— The Latins call it Aurum pitritm, Aurum primum, Aurum obrizum, Auriim coBum.

The Moderns frequently call it Gold of 24 Carats ; but, in Reality, there is no fuch thing as Gold fo very pure ; and there is always wanting at leaft a Quarter of a Carats. Gold of 22 Carats has one Part of Silver, and another of Copper: That of 23 Carats has half a Part, /. e. half a twenty-fourth of each. See Carat, and Alloy-

Souteroue maintains, that the JElcBrtrm of the Antients was Gold of 19 Carats; or four Parts- Gold, and a fifth Sil- ver- — From an Ordonance of King John of France, it ap- pears that the Gold then ftruck at Farts was of 19 Carats f ; and yet 'tis added that it was the beft and fineft Gold then known on Earth.

In England, at this time, the Standard of Crown Gold is 22 Carats. See Guinea.

Cloth of Gold, i f e S Cloth of Gold.

Gold Money, ■ 5 ? Money.

'Potable Gold, Aurum foia$i?e, fee Potable Gold.

FiilminatingQoLT>,Aurumfulminan$, fee Fulminating,

Gold, in Medicine, and Chymiflry — The Chemifls make feveral Preparations of Gold for Medicinal UTes; as Salts, Mercuries, and Tinctures of Gold- but 'tis a Point not yet well agreed on whether Gold have any real Property whereby it may be of Ufe of Medicine. — ■

The moil antient Phyficians are all filent on the Matter : The Arabs are the firft who mention it in this Quality. — Avice?ma attributes extraordinary Virtues to it; but he fpeaks on Conjecture more than Experiment. And yet it is pretty certain Gold mufl have an Effect : A Quantity of Gold Filings being taken by a Pcrfon in a Bolus, he was very well purg'd thereby: But this might well be owing to the great Weight of its Particles, which impinging violently againft the Glands of the Inteftines, promoted their Vibrations, and'thus exprefs'd the Humor fecreted therein. Beraus, in a Letter to Bartholin relates, that having heated an Ingot of fine Gold feveral times red hot, and extinguifh'd it as often in Wa- ter, he found the Weight of the Ingot confidcrably dimi- nifli'd ; upon which, proceeding to evaporate the Water, he drew a little Quantity of Gold from it. Hence it appears, that the fubtileParts of the Gold pafs into the Liquors it is extinguifh'd in ; and hence, 'tis argued, it may have confl- derable EfFefts.

Hotwithflanding the fmall Number of Experiments where- on the Medicinal Efficacy o^ Gold is founded; the Aichy- mifls will have it contain the Radical Balm of Life, for the retrieving of Health and Youth, and the Removal of all Difeafes. Gold, according to them, contains a Sulphur friendly to Nature, like that of the Sun, which animates the whole Univerfe ; And on this Principle they have form'd

a thou-