1000000030

J02

only,

~nd

not by rlinill.¡ion; bccaufe, though thefe oil,

will fwim on warer, yet they will not rife in

v~pours

without a greater degree

heat,

When the elfcnrial oil is come Ol'er, if the plant be

expof~d

tOa

n~ked

fi re, wirhout the addition of water,

Qnd the hm be increafed a little, a phlcgm will rife lhat

gradu.lly grows acid : after which, if the heat be increa–

red as occafiQn requires, there will come over a thicker

and heavier oil ; fromfome a volatile alkali; and lall of

all, a very rhick, black, empyrcumatic oil.

When nathing more rifes Wilh the ílrongeíl degree of

lIm, there remains of the planr a mere coal only, c.lled

the

(" /'II/I /lMr/" ,,,,,.

Itrr3

damnaln.

This cod when

blHlIl

f. lls into

~lhes,

which being lixiviated with wa–

ter

~ive

a fixed alkali.

is obfervable, that in the diOillation of plants which

yield an acid and a volalile alkali, tbefe two rahs are

ten fOllnd quile dininél and reparate in lhe

fam~

recciver;

which feems very extraordinary, coofideriog thal they

are narurally difpofed

lInite, and llaVe a great allinity

Wilh one aootha. The reafon

this phenomenon is,

that lhey,are both combioed with much oil, which elP.–

barralfes them fo

~hat

they cannot unite to form a oeu–

tral fah, as they would not Cai! 'to do were it not for

that imp3diment,

AII "egetables, except fuch as yield a great deal of

volalile alkali, beiog burot io ao open fire, and fo as to

flanle, leave in lheir

~n,es

a lu ge quantity

an acrid,

t~uOic,

fixed alkali, But iCcare. be taken to fmother

Ihem, fo as

prevent their R"ming while Iheyburn, by

covering them with fomething !1m may continually beat

down again whal exhales, the

C~h

obt.,ined from their

~Ol

's w,lI be much

s acrid and cauílic : Ihe callfe

whmof is, that Come pan of the acid and oil of Ihe

rl, nr being derained in Ihe

burni~g, an~ ílo~ped fro~

bein" dillipaled by the fire, combtnes wuh

1l'5

alkall

t here fahs crynallize, and being much milder rhan the

co~mlOn

fi xed alkalis nl1y be ufed in medicine, and ta–

ken inre,nally. They are "lIed

Tachen;,,!'s/a//J,

be–

canfe invented by rhat chemin.

M~rioe

planrs yield a fi xed alkali analogolls to rhat of

fea. Calt. '\s for all other plants or vcgetable fub{lan–

ces, the fi xed alkalis obtained from rhem, if righdy pre–

pared and

rhorou~hly

calcined, are all perfetlly alike,

and of ¡he fame nature

The la{l obfrrvation we have to make on the pro·

dd lion of a fi xed alkali is, that if the plant you intend to

workIrpon be íleeped or boiled in warer before you buro

it, a much fmaller

qu~ntity

of falt will be obtained from

it ; nay, it will yield none al all. if rcpeated boilings

have robbed it enrirelyof thofe faline parricks whichmuíl

necell'arily concur with irs earth tO form a 6xed alkali.

The

ANALYSIS

AN IM AL SUBSTANCE$ ,

SUCCULENT animal fub{lances, fu ch as new·killed

fl elh , yield by expreOion a juice or liquid, ",hich is no

orher rhan rhe phlegm, replele wilh all the principies of

Ibe animal body excepl rhe eanh, of which il contains

hUi li de. The hard or dry parts, fuch as rhe horns.

bones,

yiel" a fimil.r juice, by boiling them in wa–

ter. TheCe juim become thick, Jike a glue or jelly,

when their wateey pans are evaporated; and in this

n~te

they are true exrratls of animal

matt~rs.

Thefe

juiccs affol'd no cry{lals of e!fenri,1 falt, like thofe ob–

tained from vegetables, and Ihew no fign eirher of an a–

cid or an alkali.

Great parr of the oi! which is in the flelh

animal.

may be eafily feparated Wilhout the help of fire; for ir

lies in a manner by itfelf:

is commonly in a concrere

form, and is called

j al.

This oil , fomewhal refemble.

the fal oils of vegerat>les; for like rhem it is.mild, unc–

tUIlUS, ind,!foluble in fpilit of wiDe, and is fubrilized

and auenuated by the atlion of fi,e. Hut Ihere is nor in

animals. as in vegttables, any lighr e!fential oil, which

rifes wirh the heat of boiling water; ro thal, prop.erJy

fpe.lking, animal! contain bUl one fort of oil.

Few animal Cubfbnces yield a perceptible acid. Anu

and bees are almoff the only ones from which any can

be obtained; and iDdeed the

qu~.ntity

which rhey

yicld is very fmall,

rhe acid irCelf is extremely weak.

The reafon thereof is, rhat as aOlmals do DOt ·dmv.

thei r nourilhment immediately fromrhe earrh, but feed

wholly eirher on ,'egetables or on rhe flelh of olher ani–

mals, the miom l

~cids,

which have already undergÓne

a great change by Ihe unioncontra,qed berweenrhem and

the oily mauers of lhe vegetable kingdom, emer irlro a

cloler union and combinarionWilh rhefe oily pam while

rhey are pJffing rhrough rhe organs and Oniners of ani–

mals; whereby their properties are deílroyed, or at leaff

fo impaired Ihat they are no longer fenfible.

Anim.1matters yield in diffillarion, fi rfl, a phlegm,

and then, on increafing rhe fire, aprettyclear oil, which

gradually becomes rhicker, blacker, more

(eti~,

"nd cm–

pyreum~, ic.

accom~anied

with a great deal of

1'0-

latile

~Ikali;

and i( the 6re be raired and kept up rill no–

thing'more comes over, there will remain in rhe diflilling

ve!fel a coal like Ihat of vegetabits; except rhar when

ir is reduced ro alhes, no ñxcd alkali, or at lea{l

very

linlt, can be obtained fromthem, as from rhe alhes of

vegetables, Tltis arifes (rom hence that, as we faid

before, rhe faline principie in animals being more inti–

marely unired wirh lhe oil rhan it is in planrs, and beiog

confequendy more attenllared and fubtilized. is too vola–

rile ro enrer inro the combination o( a fixed alkali: on

the contrary, it is more difpofed rojoininrorming a vo–

latile alkali, which on this oceafion does nOI rife ril!

afrer the oil. and rhere(ore muíl cerrainly be the produc–

tion of the fire.

The chyle, and Ihe milk

animals which (eed on

pIaOlS, Oill retain fome likcnefs to vegetables; becanfe

Ihe principies o( which rhefe liqaors are compofed hal'e

nOI gone rhrongh all the

chang~s

which they mu{l fufl'er

oefore they cnter imo,rhe animaf.combination.

Urin" and fWfal are excrementitious aqaeous liquors,

loaded chiefly wirh rhe faline paniclcs which are of no

fervice rowards Ihe Aourilhment of the animal, bUI paCs

through irs firainers wirhout receiving any alteration;

Cuch as the neurral falts which have a fi xed

alk.li

for

rheir bafis. and parricularly rhe

fea·f~lt

II'hichhappens to

be in rhe food of animals, whelher ir exill thmin nalu–

rally, as i, does in Cume plams, or whether the animali

eat il

pJeaf~

tbeir palates.

Tbe