1000000030

"ahs·eyu,

&c. according

the fubnanw diITulved.

lf,

inllead of evaporating the liquor, a nxed 11kali

mixed thcrewith, the abforbent matlcr, that

WJS

dif·

folved by the acid, wia precipitate in the furn¡ of a

"{hite powdcr, which is c;-¿lIed the

",ogif/e'l

coral,

pearh,

&c.

'!he Acid o[Vinegnr w nhined 'UJilh coN er. Ve,degrit.

C,yJlah olCopper. 'Jhit Combinalion

dml/lp~uflded.

Spi,il

Ve,deg,it.

INTo a large matraS' put verdegris itt powder. Pour

on it dinilled vinegar tO the depth of four nngm breadth.

Set the matras in a moderate f.1nd·heat, and leave the

whole in digeUion, /haking it from time to time. The

vinegar will acquire a very deep blue.greeo colour.

Wheo the liquor is fulliciently coloured, pour it off by

inclination. Put Come fre/h vi negar into the matras;

digen as before; and decant the liquor again when it is

fufliciently coloured. Proceed in this manner till the

vinegar will extra(l 00 more colour. Thm will remain

in me matra.! a confiderable 9uantity of undiITolved mat·

ter. The vinegar thus impregoated with verdegris is

called

lin{/ure

caNu.

Mix thefe feveral tin(lures, and evaporate them with

a geotle heal: to a pellicle. Then fet lhe liquor io a cool

place: in the fpace of a few days

greal many crynais

of a mon beautiful green colour wil! /hOOI lhereio, and

nick to the frdes of the veITe!. Pour off the liquor from

the crynals; evaporate it again to a pellicle, ana fet it

by to cryflallife. Conlinue lhefe evaporalion! and cry·

nallifations, ti11 00 more crynals wil! /hOOI in the liquor.

T hefe are ca11ed

cryJlais o[ coppe"

and are ufed in paint.

ing. To this combioation of lhe acid of vinegRr with

copper the painlm aod dealm have given them thel itle

dif/illed "e,degrit.

Verdegris is prepared at Montpe11ier. To make it

they lake very elean plales of copper, which they lay,

one over anolher, wilh hufks of grapes belweeo, and

afler a certai" time take lhem out. Their furfaces are

tben covered a11 over Wilh a very beauliful green crufl,

which is

"erdeg,it.

This verdegris is nouling but cop·

per corroded by the acid of tartar, analogous to the acid

of vinegar, which abounds in the wines of Languedoc,

and efpecially in the rape, huO(s, and f10nes of grapes

that have a very auflere talle. Verdegris is a fort of rufl

of copper, or copper corroded and opened by the acid of

wine, .bul nOI yel converted entirely in10 a neulral fah :

for it is DOt foluble io water, nor does it cryfiallife.

This arifes (rom its not being nnited Wilh a fu fficienl

quantity of acid. The defir.n of the operation here de·

fcribed is to furni/h lhe verdegria with the quanlily of

acid requífite to make it a true metallic falt

for which

purpofe diflilled vinegar is very nt.

Cryflals of copper may be obtained, Wilhout employing

verdegris, by makíng ufe of copper Itrelf diITol ved by rhe

acid of 1Iinegar, according 10 rhe method pra(lifed with

rerpell ro le,d, as /hall be /hewn hereanet'. Bu! verde·

grii

generally ufed, hecaufe í! diITolves fooneil; it

be·

ing a copper already half difl'olved by ao acid correfpon.

den( to that of vinegar.

Cryflala of copper are decompounded by the a(lion of

VOL,

U, NO/H'

fire alune, without any additament; becaufe the acid of

vinegar adhms but loofely to copper. In orJer to de·

compound this falt, anJ extra(l ilS .cid, it.mufl be pUl

into a reton, and diflilled in a reverberarory rurnace with

degrees of 6re. An infipid phlegm

rif~s

firfl, which is

rhe water retained by rhe falt in cryflallifing. This

phlegmis fuccecded by an acid liquor, which rifes in too

form of white vapours lhat fill the receiver. Towards

the

e.nd

of thedífl"lalion lhe nre mufl be violeotly urged,

in order to raife rhe f1rongefl and mofl fixed acíd. At

lan Ihere remains in rhe relon a black maller, which is

nothing bUI copper, that may be reduced by mehing il

io a crucible with one part of fahpelre and two partS of

tartar.

fimílar acid, bUI 910re oily, and in a mucll

[maller quantity, may be obtaioed from verdegris by di–

¡¡illarion.

The acid, \\hich in this diUillarion comes over after

the nrfl phlegm, is an exceeding Urong and concenrrated

vinegar.

is kno\Vn by the title

/pi,il

"e,deg,it.

'Jhe AcM o[ Vinega, combin6d 'Wilh Lead. Cerufo.

Sali o,

Slsgar 01

Lead. 'JhiJ

C~mbinalion

decom·

pounded.

Ino the glafs head of a cucurbit put thin plates of

lead, and fecure rhem fo thar lhey may not faH out when

the head is put upon the cucurbir. Fil

lhis head to

a wide·mouthed cucurbit containing fome vinegar.

Set

it in a fand·bath; lure on a receiver, and diUíI wilh

gentle heat for ten or twelve hours. Then rake off the

he.ad

:. in it you will fiod rhe leaden platel coveréd, and,

in a manner, crufled over witb a white matter. T his

being bru/hed off wirh a hare's foot is )Vhal \Ve call

ce·

rufo.

T he leaden piares rhus cleanfed may be employed

again for the fame purpofe, rUI they be wholly converted

into cerufe by repeated diflillations. During rhe opera·

tion there will come over inro the receiver a liquor fome·

whal turbid and whiri/h. This is a difiilled vinegar

whích fome lead is diITolved.

Reduce a quanrity of cerufe into powder; put it in\o

a matra. ; pour on it twelve or fifreen times as much di·

fiílled vine2ar; fet lhe matras in a fand·bath; leave the

matter in digenion for a day, /haking il from time to

time: then decanl your liquor, and keep it apan. Pour

fre/h vinegar on \Vhal is lefl iD tbe matras, and digefl as

before. Proceed thus tíll you have diflolved one half,

or two Ihirds, of the cerufe.

Evaporate to a pellicle theliquors you poured off from

the mufe, and fet themin a cool place. Greyi/h cryfl:us

will /hoot therein. Decan! the liquor from lhe cryflals ;

evapome it again to

pellicle, and fer it by to cryllallife.

Proceed thus

ev~porating

and cryUallifiDg, as long as any

cryllals will {hoOt. Díflolve your crvllals iDdíUilled

vinegar, and evaporate rhe lolulion, whichwilllhen /hoot

inro \Vhiter and purer cryflals. Thi. is rhe

fali,

fllg.,

o[ I,ad.

Lead is eafily difl'olved by the acid of vinegar.

be barely expofed to the vapour of rhal acid, in furface

io corroded, and converted into a kind of calx or white

rufl, much ufed in painting, and knowe by rhe name of

mufo,

1vhil. /tad.

lJut this prep,ulion of lead i.

pot comblned wirh

fuflicienl quanliry of acid 10 convert