1000000030

a fmal! furfdCe expofed 10 Ihe air, by Ihe eOnlaél of

whieh Ihe

ev~poration

of aoy Ihiog whalever is exceed·

iogly promoled.

'lo

, rocur!

Ihe fixrd

Sall

01 a PI.IJI,

óurlling

afttr

Ih.

malln<r

TachtniuI.

JNTO ao iroo pOI pUl lhe plant whofe falt you

de~r~

oblaio io lhe manner of Tachenius, aod 'fet il over a

lire, nroog eoough tO make its botlom red·hot ; at the

fame timecover your plaot with a plm of iroo, that

m~y

Jie im1l1edi.ltclyupoo it io the pOt o The

pl~ot

will grow

bbck, aod fruoke

con~derably;

bur will OOt flame, be·

caufe il hath 001 a fulacieot cornmcoication with Ihe

airo T he black fmokc ooly will efcape through the io·

terniee lefl belweeo the

~de

of the pOt aou the rim of

the plate; w!tieh, for that purpofe, fhould be made fo

as oot tO fit exaflly ioto the pOI. From time to Ime

take up the iroo plate, nir the plaot, aod cover it agaio

immediately, to preveot its takiog fire, or to fmother ir

if it fhould

h~ppeo

tO fiame : go 00 thus till tbe black

fmoke ceafe.

Theo take off the iroo plate : the upper part of the

half. burot plaor will take fiJe as fooo as the air is ad·

mitted, coofume gradually, aod be reduced to a white

afh. Stir yOUl mmer with ao iroo wire, that the uo·

dwnofl parts, which are nill black, may be fucceffively

broughl uppermofl, take fire, aod buro to IVhile afhes.

Co 00 thus as loog as you perceive the lean blackoefs

remaioing. After lhis, Jeave your afhes fome time looger

on the fire; but nir them

fr~quently,

to the cnd that,

if any black partides filOuld lIil! be lefr, they may be

entirely confumed.

Your afhes being thus prepared, lixiviate them with

feveo times their quaotity of wm r, made to fimmer o·

ler the fire, and keep flirriog it with an iroo ladle.

T heo fiher the liquor, aod evaporate it to dryoefs io ao

iroo por, nirriog it ioceff,lIuly lowards the eod, lefl the

mamr, wheo it grows fliíF, fhould adhere too dofeJy

to the veffcl. Wheo all the humidityis

~vaporared,

you

wil! have a Calt of a darkifh colour aod alkalioe oalure;

which you may melt io a crucible, aod mould ioto cakes.

T bis is the fixed fal! of plaolS, 'prepared iD the maooer

of Tacheoius.

'lo

m,d,r

Fi"ed Analil

wrJ

tauJlie

Ó)'

meaRI

01 Lime.

'lhe Ca'if/ie Slolle.

TAKE a lump of nelVly burot quick.lime, thar hath

DOt yet beguo

Oake io the air : put it ioto a 1I0ne pan,

aod cover it with lwice its weight of the uowafhed afhes

of fome plaot thal are fulI of the falt you defign to reo·

~er

caun ic. Pour on !hem a great quaotity of hOI wa·

ler; let IhcmOeep in il 6ve or

hours, and then boil

rhem geotly. Filter the liquor Ihrough a thick eaovas

bag, or through browo 6!teriog paper fupported by

lioen doth.

Evaporale the 611md liquor io a copper bafon fet over

Ihe fire ; aod therewill remaioa falt, whichmun b. pUl

iOlO a crucible fel in the fire. JI \ViII meh, aod boil for

fomt time ; after which it \ViII be Oill, and look Jike an

oil, or mthcd

f~t.

When it comes 10 this condilioo,

pour il OUI OD

very ho! copper piate, aod 'UI il iDIO

oblong taperiog Oip!, before it grow hard by cooling.

PUl thefe Oips, while they are Oill hOI, iOlo a very dry

glafs bOltle, aod [eal il hermetically. Thi! is the

eauJlte

flor.e,

WnllIM ta,((lie.

'[he

Anll~:fiJ

Soql.

TAKE wood·fool from a chiOloey ullder which no aoi·

mal maller hath becod,effed or burn!: pUl it ioto a glaf,

rllon fet io a reverberatiog furnace; lute 00 a receiver,

aod begin to diOill wirh a degree of heal fOOlewhat lefs

thao lhar of boiliog water. A coofiderable quamily of

limpid phlegmwill come overo Keep the fire io the fame

degr~e ~s

loog as aoy of this phlegm rifes, bUI increafe

it when the drops bcgin 10 come OOIV; and Iheo there

will afeeod a good de.1of a milky water. Wheo Ihi,

waler ceafes to ruo, chaoge the receiver, aod iocreafe

your fire a little: a yellow volatile fah will rife, aod

nick to the

~des

of rhe recei,er. The fire ought now 10

be very fierce, aod, if fo, \ViII force up at rhe fame lime

a very thick black oil. Let the veffeh cool: you will

fiod a fal ioe maner rifeo inlo the oeck of Ih. reton,

which could 001 pafs over ioto the receiver: in Ihe bot'

tom of Ihe relon \\'ill be a

tapUI rnOrluulIJ,

or black

charred fubnaoce, the'upper pan of which will be crun·

ed over Wilh a fal ioe maller, like thal io lhe neck of the

relort .

As we are al prefent ioquiriog inlo Ihe nalure of ve.

gelables ooly, it is evideotly ncceffary Ihat we chufe a

foot produced by buroing vegelables alone. SOOI, Ihough

dry in appearaoce, contaios oeverthelefs much humidilY,

as appears from this aoalyfis; feeiog Ihere comes over

fi rn a coofiderable quaotity of phlegm, thal dOlh 001 feem

ro be impregoated with any priociple, excepl perhaps ao

extremely fublile, falioe, and oily maner, that commu·

nicaIes to il a difagreeable fmell, fromwhich it canoOI

by aoy meaos be entircly freed.

The volatile alkali oblaioed from fool is, iD a double

reCpeél, Ihe produél of Ihe fire. In thefirn place, Ihough

it derim ils origio wholly from wood, or olher vege.

rabies, which, wheo dinilled in clore veffels, yield 00

volalile alkali al all, yet it produces fuch a falt when a·

oalyfed io the prefeol manoer: wheoce it mun be iD·

ferred, thal the principies of thofe vegelables are mela·

morphof.d into a I'olatil. alkali, by bcing burnr iDIhe

opeo air, and fubl imed in the form of foot. Secondly,

Ihough fool, when aoalyfed, yields a great deal of this

fah, yel this Cah doth oor formally pre·exill Ihereio;

for it dotb oot rife till after Ihe phlegm, nor wilhom a

very confiderable degree of hear : therefore fool cootaios

only the malerials neceffary to form Ihis falt ; rherefore

Ihe perfeél combioatiooof this falr requires that the force

of fire be applied a fecond time; rhercfore il is. as was

faid, doubly the produél of Ihe fire.

The falioe maller IVhich ' IVe fiod fublimed iDIO Ihe

neck of Ihe retort, aod which alfo forOls rhe crun that·

covers the

,apul ,norluum

of the

COOI,

appears byall

ehemicdJlri.ls

to be an ammoniacal fal l ; thal is, aoeu·

tral fall, coofifling of ao acid and a volalilealkali, This

ammoniacal fall rifes only iOlo Ihe neCKof rhe retorr,

and doth oot come over into the reccívcr; becaufe it is

but femi·volalile. \Ve !hall ueal more al large of the

produaioa