Page:Cyclopaedia, Chambers - Volume 2.djvu/592

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again the Lands. &c. into my own Hands, and to recover the PoifeffioD by my own act, without the Affiftance of Judge, or other Procefs.

RE-EXTENT, in Law, a fecond Extent made upon Lands or Tenements, on Complaint made, that the former Extent W as partially executed. See Extent.

REEVE of a Church, is the Guardian of it; or the Church- Warden. See Church-Warden.

So, Shire-Reeve is the Sheriff, or Guardian of a County. See Sheriff-

And Port-Reeve, the Warden of a Port or Haven. See Port.

REEVING, in the Sea Language, is the putting a Rope through a Block. — Hence, to pull a Rope out of a Block, iscall'd unreev'mg it.

REFECTION, among Monks and Ecclcfiafticks, a Repaft or fpare Meal,- meerly fufficing for the fupport of Life. See Meal and Repast.

Refection is alfb ufed in antient Authors for a Duty or Service incumbent on any Perfon to provide Meals, for Ecclefiafticks, or even Princes. See Procuration.

REFECTORY, or Refectuary, a fpacious Hall in Con- vents, and other Communities, where the Monks, Nuns, &c. take their Refections or Meals in common.

The Refettory of the Benedictines of St, George at Venice^ de- figned by Palladia, is one of the finefi in the World. Daviler.

REFERENDARIUS, in antient Cuftoms, an Officer who exhibited the Petitions of the People to the King; and acquaint- ed the Judges with his Commands.

An Officer of this Kind, Spelman obferves, we had in JSsg- land, in the time of the Saxons.

REFERENCE, in Writing, <&c. a Mark, relative to ano- ther fimilar one in the Margin, or at the Bottom of the Page ; where fomeching omitted in the Text, is added ; and which is to be inferted either in Reading or Copying. See Cha- racter.

A Copiit muft be very expert at taking References. — Referen- ces are alio ufed in Books ; where, things being but imperfectly handled, the Reader is directed to fomc other Part or Place where they are more amply explained.

Dictionaries are tull of References ; denoted by See, or Vide. —By means of thefe References, the Dictionarift fettles a Cor- refpondence between the feveral Parts of his Work ; and gives his' Dictionary moil of the Advantages of a regular continued Treaufe. See Dictionary.

Indices or Tables are only References to the ieveral Parts of

the Work, where the feveral Matters are handled. See Index.

REFINING, the Art or Act of purifying a thing,- or of

rendering it finer, cleaner, and purer. See Purifying, and

Clarifying.

Refining is chiefly understood of Metals, Sugar, and Salts. See Metal, &c.

Refining of Gold.

The Refining of Gold is perforra'd three Ways : Either with Antimony, with Sublimate, or with Aqua-Fortis ; which laft Method, much the moil: ufual and leaft dangerous of the three, is calfd Depart, or parting; the Procefs whereof fee under the Article Gold and Depart.

Method of Refining Gold with Antimony.

They here ufe a Wind-Furnace; (a Defcription whereof may be feen under the Article Furnace,) with an ordinary Crucible, of a Size anfwerable to the Quantity of Gold to be refined ; ob- ferving that the Gold and Antimony together don't above half fill it.

The Gold being melted in the Crucible, the Antimony is thrown in, in Powder.— The Proportion of the Mineral to the Metals, is eight Ounces to a Pound, if the Gold be between 22 and 16 Carrats fine; If it be beneath 16 Carrats, they ufe about five Quarters of a Pound to eight Ounces: The coarfer the Gold, itill the more Antimony is required.

As foon as the Antimony is in the Crucible, 'tis cover'd up; and after charging the Furnace with Charcoal, they put on its Capital.; which itands till fuch time as the Crucible be left quite bare ; then, the Capital being taken off, and the Crucible fet to cool in the Furnace it felf, till fuch time as it may be taken out by the Hand, they break it, to get out the Button or Culot, which is a Mafs of fine Gold remaining at the Bottom with the Fieces of the Antimony the Silver and Copper alloy and fometimes little Particles of Gold it felf over it.

Though the Gold thus prepared be very pure, yet the Anti- mony gives it fuch a harfii brittle Quality, that it ceafes to be Ductile; and mult be fofren'd by the Fire with Salt-petre and Borax, to bring it to itfelf.

For this Operation they prepare what they call a Dry-Coppel; that is, aCuppelmade of Crucible Earth, which does not im- bibe like the Cuppels made of Ames See Coppel.

The Coppel being fufficiently heated in the refining Furnace, they put the Gold in it, and cover it up with Charcoal.

As foon a; the Gold is diflblved, which is very foon, by rea- fon of the remains of the Antimony, they blow'it with the Bel- lows to drive the Mineral entirely away, which now goes off in Smoak; adding to it, as foon as the Fumes ceafe, a little Salt- petre and Borax, in Powder ,- which collect the Impurities re- maining upon the Diilblution, and fix the Gold in the Coppel, in form of a Plate.

The Gold being taken out of the Coppel, and melted a-freflt in a Crucible, with an Addition of two Ounces of Salt-petre and as much Borax, in Powder to each eight Ounces of Gold, as foon as it ceafes to fume, they caft it into an Ingot; which upon trial is found 23 Carrats, 26 thirty feconds finer.

As to the Particles of Gold which may have been left behind with the Alloy in the Fasces of the Antimony, they get them out by a dry Coppel, with the fame Meltings and Ingredients as are ufed in foftening the former.— And when they are affured, by the Eflay, of the Share of Gold that Matter contains, they refine it to feparate the Copper; and afterwards make the De- part.

As to the Gold which may be left (ticking to the dry Coppels, they get it out by breaking,' and pulverizing the Crucibles, and by repeated Lotions of the Powder thereof in feveral Waters; much after the manner of the Lavadero's. See Lavadero.

Refining of Gold hy mea?is of Sublimate.

The Procefs is begun like that with Antimony ; i. e. in the fame Furnace, with the fame Coal, the fame Fire, and the fame Crucibles.'

The Gold being melted in the Crucible, they caff: in the Sub- limate, not puiveriz'd, but only broke in Pieces.— As to the Pro- portion; to 8 Ounces of Gold to be refined, they put anOunce, or Ounce and a half, or even two Ounces, if the Gold be of 22 Caracts; three Ounces, if 20 Caracts; and 5 or 6 Ounces, if it only be from 18 to 12 Caradfs. In which laft Cafe they part the Sublimate into two ; putting half at a time, with the Gold, into a new Crucible; which, when the Operation is over, leaves the Gold of 18 or 20 Caracts, according to its finenefs be- fore—After this, they raife it by the Fire, as follows;

The broken Sublimate being put into the Crucible with the melted Gold, the Crucible is immediately cover'd up, to fmother the Mineral : Which done, the Furnace is filPd with Charcoal, and the Capital put on. — A quarter of an Hour afterwards they take off the Capital, lay the Crucible bare, and give the Gold Air, ing on the liquid Gold, with a Pair of Bellows, the NofTle where- of is crooked.
 * . e. blow off all the Allies and other Impurities that may be float-

This they repeat again and again, till all the Impurities of the Gold being carried off, by virtue of the Sublimate, it be found of a bright glittering Colour : After which 'tis taken out of the Crucible, and the Gold call into an Ingot.

The Method of Refining by Sublimate is both more complete and cheaper than that by Antimony; but they are both exceed- ingly dangerous, by reafon of their fulphurous and arfenical Ex- halations : The only difference in their Malignity confifting in this, that the Poifon of the Antimony is flower than that of the Sub- limate. See Sublimate, &e.

Gold may alio be refined wich Lead and Aihes; but this is a Method felciom ufed, excepting in Effays. See Essay.

Refining of Silver.

There are two Ways of refining Silver ■. The one with Lead; the other with Salt-petre. The belt and cheapeft is that with Lead; though that with Salt-petre ftill obtains in many Places a for want of Workmen who underftand the Procefs of the latter.

We ffiall here only give that with Suk-petre; referring for the other to the Article Silver*

Refining with Salt-petre is perform'd in a Wind-Furnace. — The Silver to be refined having been reduced into Grains, of the Size of" a little Pea, by pouring it, when melted, into a Tub of com- mon Water; 'tis heated over 2gain in a Boiler. After this they put it in a Crucible, and along with it, to every eight Ounces of Metal, two of Salt-petre.

The Crucible is now covered up with an Earthen lid, in form of a Dome, exactly luted ; which lid, however, is to have a lit- tle Aperture in the middle.

The Crucible being pur in the Furnace, and cover'd with Char- coal, which is only to be lighted by Degrees, at length, they give it the full force of the Fire to put the Metal into a perfect Fuii- on. Thus they repeat three times fucceilively, at an Interval oi J a Quarter of an Hour.

After the third Fire they uncover the Furnace, and let the Cru- cible cool; and at length break ir, to get out the Silver, which is found in a Button or Culot; the Bottom whereof is very fine Silver; and the top mix'd wich the Faeces of the Salt-petre, and the Alloy of the Silver, and even fome Particles of fine Silver.

The Culot being feparated from the Impurities, is melted in & new Crucible, and into the Diffolution is thrown Charcoal Duft, and the whole briskly work'd together. Then, the Crucible being cover'd up again, and the Furnace charged with Coal, a fe- cond Fire is given it,

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