PEARL, 
442 
wire, and put them into a glafs ; clofe it up, and fet them 
in the fun'to dry. After they are thoroughly dry, put 
them in a glafs matrafs into a ftream of running water, 
and leave them there twenty days 5 by that time they 
will contract the natural hardnefs and folidity of pearls : 
then take them out, and hang them in mercurial water, 
where they will moiften, fwell, and affume their 
oriental beauty ; after which, fhift them into a ma¬ 
trafs hermetically doled, to prevent any water coming 
to them, and let it down into a well, to continue there 
about eight days: then draw the matrafs up, and, in 
opening it, you will find pearls exadly refembling ori¬ 
ental ones. 
The mercurial water is thus prepared : Take plate-tin 
of Cornwall ; calcine it, and let the calx be pure and fine; 
then, with one ounce of the calx and two ounces of pre¬ 
pared mercury, make an amalgam; wafh it with fair w'a- 
ter, till the water remains infipid and clear; then dry the 
amalgam thoroughly, put it into a matrafs over the fur¬ 
nace, giving it fuch a heat as is requifite for fublimation. 
When the matter is well fublimated, take off the matrafs, 
and let it cool. Take out that fublimate, add one ounce 
of Venice fublimate to it, and grind them together on a 
marble ; put this into another matrafs, dole it well, and 
fet it upfide-down in a pail of water, and the whole mafs 
will diffolve itfelf, in a little time, into mercurial water: 
this done, filter it into a glafs receiver, fet it on a gentle 
afh-fire to coagulate, and it will turn into a cryftalline 
fubftance : beat this in a glafs mortar, with a glafs peftle, 
to a fine powder ; fcrain it through a fine fieve, and put 
it into a matrafs, flop it clofe up, and place it in balneo 
marise ; there let it remain till it refolves again into wa¬ 
ter, which will be fit for the above-mentioned ufe. Pojll. 
Diet. Com. 
The fieur Janin, or Jaquin, having obferved, that the 
feales of a little fifti called the bleak, found plentifully in 
the river Marne, had not only all the luftre of the real 
pearl, but that, after beating them to powder in water, 
they returned to their former brilliance upon drying; be¬ 
thought himfelf of fetting a piece or little mafs thereof 
in the cavity of a bead or grain ofgirofol, which is a kind 
of counterfeit opal made of glafs, and bordering much on 
the colour of pearl. The difficulty was to get it there, and 
when it was within to fpread it equally throughout the 
bead. A little glafs tube, fix or feven inches long, and a 
line and half in diameter, but very fiiarp at one end, and 
a little crooked, ferved for the introducing of the mat¬ 
ter, by blowing it with the mouth, after having taken up 
a drop of this mixture with the pointed extremity of the 
tube ; and, to fpread it throughout the inner circumfer¬ 
ence, he contented himfelf to (hake it gently a long time, 
in a little ofier bafket lined with paper. The pulverized 
feales, fattened by this motion in the infide of the bead, 
refume their luftre as they dry. To increafe this luftre, 
in winter, they lay the beads in a hair fieve, or a bolting- 
cloth, which they lufpend to the ceiling, and under it, at 
fix feet diftance, they lay heaps of hot allies. In fummer 
fthey fufpend them in the fame manner, but without any 
fire. The pearls, thus well dried, become very brilliant, 
and nothing remains but to ftop up the aperture, which 
is done by melting wax, conveyed into it with a tube like 
that ufed in introducing the powdered feales. After 
clearing off the fuperfiuous w'ax, the)'’ perforate the pearls 
with a needle, and firing them, and thus they form neck¬ 
laces. 
To blanch and cleanfe Pearls. Firft foak and rub them 
gently in bran-water, then in milk-warm w'ater, and laft 
of all fteep them in mercurial water; then firing and hang 
them in a glafs, clofe it well, and fet them in the fun to 
dry. The bran-water is made thus : Boil two good hand¬ 
fuls of wheaten bran in a quart of water, till all the 
ftrength of the bran is drawn out; which ufe thus : take 
anew glazed earthen pan, in which put your pearls on a 
firing, and pour the third part of the bran-water upon it: 
when they have foaked, and the water is juft warm, rub 
your pearls gently with your hands, to clean them the 
better, and continue this till the water is cold ; throw off 
that, and pour on another third part of the bran-water 
that is boiling ; proceed with this as you did before, and 
when cold throw it away, and pour on the remainder of 
the water, ftill proceeding as before. After this, heat 
fair water, and pour it on your pearls to refrefh them, 
and to wa(h away the remains of the bran by fhifting 
them, and pouring on frefh warm water; this do thrice, 
without handling your pearls ; then lay them on a fheet 
of clean white paper, and dry them in a fhade ; after 
which, dip them into mercurial water, to bring them to 
perfection. Pojll. Did. Com. 
Or, pound alabafter to an impalpable powder, and rub 
the pearls therewith, very gently : this will not only 
cleanfe them, but, if you let them remain in this pow¬ 
der twenty-four hours afterwards, they will ftill be the 
better for it. White coral has the fame effect, ufed in 
the like manner. White tartar, calcined and divefted of 
all its moifture, is very good for the fame purpofe. Sait 
diffolved, filtered, coagulated, well dried, and ground, is 
as effe&ual as any of the former things for cleanfing of 
pearls, by rubbing them therewith ; and, if afterwards you 
lay them up in foine coarfe ground millet, it will contri¬ 
bute to their brightnefs. 
PEARL, /. A white fpeck or film growing on the eye. 
Any thing round and clear, as a drop: 
Dropping liquid pearl, 
Before the cruel queen, the lady and the girl 
Upon their tender knees begg’d mercy. Drayton. 
PEARL, /« The name of the fmalleft regular printing-type* of which the prefent 
lines are a fpecimen. 
To PEARL, v. n. To referable pearls : 
She let to fall 
Few perling drops from her fair lamps of light. Spenfer. 
PEART-ASH,/. A fixed alkaline fait, prepared chief¬ 
ly in Germany, Ruftia, and Poland, by melting the (alts 
out of the allies of burnt wood ; and, having reduced 
them again to drynefs, evaporating the moifture, and 
calcining them for a confiderable time in a furnace mo¬ 
derately hot. The goodnefs of pearl-alhes mud be dif- 
tinguilhed by a uniform and white appearance : they are 
neverthelefs fubjeft to a common adulteration, not eafy 
to be diftinguilhed by the mere appearance, which is done 
by the addition of common fait. In order to find out 
this fraud, take a frnall quantity of the fufpeffed fait ; 
and, after it has been foftened by lying in the air, put it 
over the fire in a (hovel : if it contains any common fait, 
a crackling and flight explofion will take place as the fait 
grows hot. 
Pearl-allies are much ufed in the manufacture of glafs ; 
and require no preparation, except where very great 
tranfparency is required, as in the cafe of looking-glafs, 
and the belt kind of window-glafs. For this purpofe 
diffolve them in four times their weight of boiling water: 
when they are diffolved, let the folution be put into a 
clean tub, and fuffered to remain there twenty-four hours 
or more. Let the clear part of the fluid be then decanted 
off from the fediment, and put back in the iron pot in 
which the folution was made; in this let the water be 
evaporated till the falts are left perfeftly dry. Keep 
thofe that are not defigned for immediate ufe in (tone 
jars, well fecured from moifture and air. 
Mr. Kirwaii, who inftituted a fet of experiments on the 
alkaline fubftances ufed in bleaching, &c. (fee Irifli Tranfi 
for 1789.) tells us, that in 100 parts of the Dantzick 
pearl-afh, the vegetable alkali amounted to fomewhat 
above 63. He has alfo given tables of the quantities of 
afltes and fait obtained from different vegetables ; and he 
concludes from them, 1. That in general weeds yield 
much more allies, and their allies much more fait, than 
woods; and that, confequently, as to falts of the vegeta¬ 
ble alkali kind, neither America, Triefte, nor the north¬ 
ern countries, poffefs any advantage over us. 2. That of 
all weeds fumitory produces molt fait, and next to it 
wormwood: 
