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130 e H E M
Exodus; andohe cooc\udes, that Mofe¡ mull have pero
forDled this operatioo by meaos of liver 01' Culphllr.
'J, ;;ptraM Gola frm all olhu ",(Iallic Su/lIm,c/I by
/11lalll ef Alllimoll)'.
HAVIHG PUt the gold you iotend to purify imo a
crueible, fet it io a meltiog furoacc, cover it, aod make
Ihe gold Aow. Wheo the metal is io fufioo, can upon it,
by a little at a lirue, twiee its ~eight of pure crude ano
timooy io pOlVdcr. aod after eaeh plojcaioo eover the
(¡ueible again inlmediately: this dooe keep the matter
in fufion for a Cew mioutes. Wheo you perecive that
me mwllie mixlure is perfe,qly mehed, aod that ils f~r·
faee begios 10 Cparkle, pour it OUI into a holl(}w iroo eooe,
prel'ioully healed, aod lmeared 00 the iofide wilh tallow.
lmmcoiately flrike wilh a h.mmer Ihe Aoor 00 whieh the
,ooe flaods; aoo wheo ,11 is eold, or at leafl Cuffieienlly
éxod, iovert Ihe eooe aod Itrike it: the whole metallie
JIlaes \ViII fall out, aud the under par! thereof, whieh
"'as at the point of the eooe, will be a regulus more or
leCs yello\V as the gold was more or leCs pureo On l!ri·
king the metajlie mafs, the regulus will freely pan from
Ihe Culphureous erul! at topo
Return this regulus ioto the erueible, and melt it.
LeCs fire will do nolV than was required before. Add
the fame quantity of aoúmooy, aod proeeeu as aL 6rfl.
Repeat the fame oreratioo a Ihird lime, if your gold be
"ry impure.
Theo put your regulus into a good erucible, mueh
larger Ihao is neeelfary to hold il. Sel your erueible io
a me!liog furnaee, aoll- hea! the maller but jull eoollgh
10 make it IIow, "ilh a fmoolh, brilliaot furfm. When
JOu fiod il thu eonditicned, point lowards it the oofe of
a loog-foouled pair of beUowI, and Iherewilh keep
gently aod CODfl~otly blowing. There 'IIi11 arift from
tbe erueiblncoofiderabk Cmoke, which lVill abate greatly
wheo you eeafe 10 blow, aod ioereafe as fooo as you be·
gin ag,io. You mull raife Ihe 6re gradua)ly as you ap'
proaeh lowards tlle eod of me operatioo. lf Ihe furfa-ce
oI Ihe metalloCe in brilliant polilb, aod (eem comed
wilh a hard erull, il i~ a ligo Ihe 6re is too weak; in
whieh eafe it mufl be inereaf;d, till the Curfaee recover
itfl Ibioiog appearanee. Al lall, wllen no more Cmoke
rifes, and the rurface of the gold looks Dea! aod green·
illt, call 00 il. by little aoo linle, fome pulmized oitfe,
or a mixture or oilre and borax. Tbe matler will fwell
up. Coolinue thus adding moro Dilre gradually, lilf 00
eommoúoo is tbereby produeed io Ihe erueible; aod theo
Jel the whole coo!. Jf you find, wben tbe gold is cold,
thal il j, 001 lough eoough, mell it over agaio; wheo it
bcgios 10 mdl eafl it io lhe lame Calt, as before ;
repeat this till it be pe,fealy duaile.
'Jofipar,¡, Silurr Irom ilI Qr(, h, mtan¡ of Sm i·
j ea/ion wilh Ltad.
BUT 10 powder ioaDiroo mortar Ihe ore from which
10u meao 10 Ceparale Ihe filver, haviog firll roafled il'
well in order 10 free ir from all Ibe fulpbur aod arfeoie
Ibal il may eontain. Weigh il exaélly: then weigh out
by itfelf eighl times as OIueh graoulated lead. Put ooe
hAII oI tbi, lead ioto a le!l, iIllMpread it equally tbe,,·
s T R Y.
00: upoo tMs bd lay your ore, aod eOI'er it quite over
with Ihe rcmaining half uf the !cad.
Place the tdl thus loadeu under the furthereod of Ihe
muffie io a eupellin,¡ furnaee. Light )'our fire , aou io·
creafe il by d~grces. If you look IhrollJlh ooe of Ihe a–
pmurts io Ihe door of the furnaee, you will pm eive th~
ore, comed wilh ealcioed lead, flVim upoo lhe meheo
lead. Prefeody afterlVar~s it will grow foft, mdl, , od
be Ihrown toward, the fides of Ihe velfel, lhe furfaee oí
Ihe lead appeariog in Ihe rIIitlfllhereof bright and nlloiog
like a luminous ¿ife: Ihe Icad will Iheo begio 10 boil,
aod emit fumes. As foon' as Ihis happeos, Ihe 6re mull
be a liule eheeked, fo thal Ihe ebullilioo of Ihe leaer
may a1mofi eOlirely Clafe for about a quarler of ao hour.
After Ihis il mull be exeitecl 10 Ihe degrce il WlS al be·
fore, Co Ihal Ihe lead may begin again to boil and
fmoke. !ts Ihinoiog fnrface will gradllally lelfco, aon
be comed with ¡wi~. Slir the whole with ao iroo
book, aod drAw in lowards the middle what fOil ob·
rene lowards the fiJes of Ihe velfel; lO Ihe end thal, ir
aoy pan of Ihe ore nlOuld Itill rem:lÍo uodilfolved by the–
Iead, it may be mixeu therewith.
Whcn you perecive that the matter is io perfeél fufioo.
that Ihe grealell pan of whal lIieks 10 the iron hook,
wheo you dip il io Ihe melted mauer, feparates from il
again, and drops baek into Ihe velftl ; and that the eX–
Iremily of !bis iollrumenl, wheo growo eold, appears
varpilbed Ofer with a Ihio, finooth, fhioiog erufl; you
may look 00 thefe as marks Ihat Ihe bufioefs is done;
aod tbe more uoiform aod evenlr the eolour of the erun
is, the more pcrfeél may you judge Ihe feorificalion
10 be.
Mallers beiog brooght to Ihis pafs, tah the tdl wilh
a pairof toogs írom under the muflle, aod pour its whok
conteots ioro '0 iroo eooe, firfi healed and greafed with
tallow. This whole opem ioo lafls about tlHCe qUart<rS
of an hour. WheRall is eold, Ihe blow of a hammer
will pan the regulus from the fcoria; and as il is 001
poffible, how perfeél foem Ihe feorificatioo be, to avoid
Imiog a ~Ide lead cootaining film io the feori•. il i~
proper lO pulverife this feoria, aod feparate Iherefrom
whatever eXleods IInder the hamme[, io order 10 add il
(1) lhe regulus.
Thl refilling of Si/ver h, Ih( !.
a cupel :apable of containiog ooe third OIore
malter than you have 10 put iOlo il: fe! it uoder the
muflle of a fumaee like Ihat defcribed io our theorelical
e1eollnls, as peeuliarly appropriated 10 this fort of ope·
m ioo. Filllhe furnaee with charcoal; Jight it; make
the cupe! red·hot, aod keep it fo till all ils moiflure be
evaporated; thal is, for aboul a good quarter of an
Mur, if Ihe euncl be made wholly of lhe albes of burol·
bQoes; anJ for a ",hole hour, ir mere be aoy w~Hled
wood·,nl io ilS eompolicion.
Rcd\le~ the regulus whieh remained alter Ihe pre.
eeding operatioo to littlóIhio plates, nauing them wilh
a fmall halllmer, aod fcpamiog them earefully f10m 411
the adhereot fcoria. Wrap thefe io a bil of paper, and
with ifOlall p,ir of 10AgS put Ihem gently ioto the cupe!.
Wl¡en me paper is confumcd, Ihe regulus will fooo mtll,
3lId.