DOI Page / Citation link:
https://doi.org/10.11588/diglit.19574#0189
i74 CRY
arfenic, one ounce of crude antimony, and an ounce of fal ar-
moniac; reduce them all to powder, and mix them together;
with this powder, ftratify pieces of natural Cryftal, in a large
crucible, putting the leaft pieces to the bottom, and the biggeft.
at the top, which ought to be fine and without fpots.
The crucible being filled with the powder and Cryftal, cover
it with another bored at bottom, lute them well, and let the
lute dry. This crucible is bored to let the fumes of the mate-
rials afcend through the hole, and by that means tinge the Crys-
tals in paffing, which they would not do fo well, if they palled
out at the fides.
When the lute is dry, fet the pot in the furnace, and cover it
with coals up to the middle of the crucible towards the top; then
put fome live coals to them, that they may kindle by themfelves
by degrees; the coals ought to be large ones, and made of oak.
Go out of the laboratory prefently to avoid the fumes, which
are dangerous, as was faid before; but prepare the fire fo well
that it may kindle of itfelf, and burn well that the bufinefs may
fucceed; and let the fire go out of itfelf, taking care that no air
can get in at the mouths of the crucibles, for that would make
the Cryftals break, and then they would be good for nothing.
When the crucibles are-grown cold, unlute them, and take
out the Cryftals, the greateft part of which will be tinged with
the colours beforementioned ; let the belt of them be polifhed
at the wheel, which will alfo brighten their colours, and make
them look like oriental ftones, and they will be fair and hard as
thev are.
All the fuccefs of this fecret confifts in the orpiment, which
rnuft be of the colour of gold ; and, if you mould not fucceed the
fir ft time, you muff try a fecond.
An admirable blue Crystal. To procure this fine colour,
take one ounce of powder of Cryftal, one drachm and fifty-fix
grains of fine fait of tartar, the whole reduced to a fine powder;
put it into a crucible covered and luted, which bake and purify
twenty-four hours in a glafs-houfe furnace, then fet it to cool
gently twelve hours in the annealing furnace, and you will have
very admirable blue, which you may cut and polifh, &c.
The tvay to make a fait of feveral vegetables, which will produce
a Crystal of a wonderful fnenefs. It has been obferved, that
the fait which ferves to make glafs, is extracted from polverine
of the Levant, from rochetta and foda ; and the way of extract-
ing it is there fhewn ; here I (hall acquaint you, that any vege-
table, that abounds with alcalious fait, is proper to make glafs
and Cryftal, by preparing its afhes as there fhewn.
Several plants are good for this purpoie, but thofe that grow
near
arfenic, one ounce of crude antimony, and an ounce of fal ar-
moniac; reduce them all to powder, and mix them together;
with this powder, ftratify pieces of natural Cryftal, in a large
crucible, putting the leaft pieces to the bottom, and the biggeft.
at the top, which ought to be fine and without fpots.
The crucible being filled with the powder and Cryftal, cover
it with another bored at bottom, lute them well, and let the
lute dry. This crucible is bored to let the fumes of the mate-
rials afcend through the hole, and by that means tinge the Crys-
tals in paffing, which they would not do fo well, if they palled
out at the fides.
When the lute is dry, fet the pot in the furnace, and cover it
with coals up to the middle of the crucible towards the top; then
put fome live coals to them, that they may kindle by themfelves
by degrees; the coals ought to be large ones, and made of oak.
Go out of the laboratory prefently to avoid the fumes, which
are dangerous, as was faid before; but prepare the fire fo well
that it may kindle of itfelf, and burn well that the bufinefs may
fucceed; and let the fire go out of itfelf, taking care that no air
can get in at the mouths of the crucibles, for that would make
the Cryftals break, and then they would be good for nothing.
When the crucibles are-grown cold, unlute them, and take
out the Cryftals, the greateft part of which will be tinged with
the colours beforementioned ; let the belt of them be polifhed
at the wheel, which will alfo brighten their colours, and make
them look like oriental ftones, and they will be fair and hard as
thev are.
All the fuccefs of this fecret confifts in the orpiment, which
rnuft be of the colour of gold ; and, if you mould not fucceed the
fir ft time, you muff try a fecond.
An admirable blue Crystal. To procure this fine colour,
take one ounce of powder of Cryftal, one drachm and fifty-fix
grains of fine fait of tartar, the whole reduced to a fine powder;
put it into a crucible covered and luted, which bake and purify
twenty-four hours in a glafs-houfe furnace, then fet it to cool
gently twelve hours in the annealing furnace, and you will have
very admirable blue, which you may cut and polifh, &c.
The tvay to make a fait of feveral vegetables, which will produce
a Crystal of a wonderful fnenefs. It has been obferved, that
the fait which ferves to make glafs, is extracted from polverine
of the Levant, from rochetta and foda ; and the way of extract-
ing it is there fhewn ; here I (hall acquaint you, that any vege-
table, that abounds with alcalious fait, is proper to make glafs
and Cryftal, by preparing its afhes as there fhewn.
Several plants are good for this purpoie, but thofe that grow
near