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cold, you \ViII fiad half as maoy more flowers as you got
the 6rfl time.
Proceed thus till you have cooverted all your regulus
iota flowers. This will require a confiderahle number of
[ublimatioos, which, as you advance. will always yidd
you a greater portian of flowers; refpeél, hOIVever, bcing
had 10 lite quantilY of regulus remaining io Ihe pat.
Of Jl I S M U T H.
'To txlrafl Bifmulh ¡"n¡ ilt O".
JlUH Ihe ore of bifmulh iOlo [mall pieees, and
Iherewilh 611 a crucible eilber of earth Or iron. Sel the
Ihe crucible io a furnaee, and lighl fuch a 6re Ihat the
bils of ore may become modermly red. Stir the ore
from lime to time; and if you perceive it craclle and
By, keep Ihe crucible comed. Al !he bonom you will
fiad a bunod of bifmulh.
JJifmulh diJolvtd b)' Acidt. Magij/trJ o¡ Difmulh.
SjI"palhtlic ¡nA.
Ino a matras put bi[mulh brokeo iota liule bits :
pour 00 il. by linle aod linle, twice as much aqua¡o/'.
lit . T his aeid will anaek the [emi-melal brifkly, aod
diffolve it entirely, wilh heat, ttl'erve[ceoce, vapours, aod
pulling up. The [olutioo will be clear aod limpid.
lf Jau would have a maginery of bifmulh beautifully
while, you mun perform Ihe di!1'olutioo wlth ao aqu.
¡orlit that is not taioted with any mixture of the vitrio·
lie acid ; for this gives tbe precipitate a dirty white co·
lour, inclining tO.grey.
Bi[muth may alfo be precipitated by the means of fix·
ed or volatile alkalis; but the preeipitate is nOI of [o
/ioe a white as wheo procurcd by the means of pure wa·
ter only.
A [olution of bi[muth prepared wilh the proper quan–
tlty of ' qua¡ortÍ!, that is, with two pans of the acid
to one of Ihe femi metal, eoale[ces into li¡tle crynals al·
mon as [oon as made.
Aq'll¡ ortÍ! oot only aéls 00 bifmulh when [eparated
from its ore, and reduced to a regulus, but anacks it e·
leo in its ore, and likewi[e diffolves at the[ame time feme
portien of the ore ilfelf. With Ihis [oIution of the ore
of bifmuth Mr Hellot makcs a very curious [ympathetic
ink. differing from all that werc known befare.
Mr Hellol prepares the liquor in the following man–
aer : .. He brui[es the ore of bi[mulh to a coar[e pOIV.
der. On twb ounees of this powder he pours a mixture
of 6ve ounces of commoo water with 6ve ounces of aqu4
¡orlÍ!. He <loes not heat the \'effcl till the 6rfl ebullitions
~ re ov~r. lIe¡heo fets it in a geot1e faed.heat, and letl
it digen there till he fees no moreair·bubbles ri[~. When
Lone appcar in this heat, he increafes it fo as to
the [olTent boil flightly for a full quaner of lO hour. It
takcs up a tinélort oearly of lite colour of brown beer.
Tite ore Ihat givrs the aqua ¡ortit thi. colour is the ben.
He then lel! the folution cool, !aying the matras 00 itl
fide, that he may decant the liquor more con,eniently
whtn aU is precipitatcd thal il Dot takeo up by the [01·
leD.t.
s t R Y.
.. The fccond veffel, into which the liquor is 6rfi d4.
caoted, he al[o lays decliniog, that a oew precipitalioo
of the undi!1'olved matlers may be oblained ; after "hich
he pours the liquor ioto a third Vtffd. This liquor mufl
not be 6ltered, if you would have the ren of lht procets
fltcceed perfealy; becau[e Ihe "qua ¡orlil Y!ould diffolve
fome of the paper, and that would fpoil the colour of
your liquor.
" Whcn this [aludan, which Mr Hellot calls the in!.
pregnalion, is thoroughly c1ari6ed by Leing decanted
time or four times. he pUIS it into aglafs baron wid. two
ounces of very pure fea·[alt. The fine white falt made
by the fuo [ucceeded bcn wilh Mr Hellot. lf that caonot
be had, eommon bay.falt purified by [olution, filtratioD,
and erynallifation, may be ufe'd ioDead of it. But as It
is rare tO meet with any of the [OTl that is oot a little
taioted with iron, the wHite bay falt is to be preferred.
The gla[s bafon he [els in a ~entle (aod.heat, Bnd kee¡ís
it there tiU the mixture be reduced by evaporalion to ao
almon dry faline mafs .
.. lf you defire tO [ave the aqua regil, the impregna.
tioo mufi be put into a.retort, and dilfiUed with the gen–
tle heat of 1 [aed·balh. But there is ao inconveoience,
as Mr Hellot obferves, in employiog a tetan; whieh is,
tbat, as the faline ma[s cannOI be nirred while it coagu·
lates io the retort, il is reduced tO a compaa cake of
coloured [alt, which pre[eo" but ooe fingle furrace to
the water iD which it mun be di!1'olved; fo that tbe dif·
folution thereof takes up fometimes 00 lefs than 6ve or
fix days. ID the bafoo, 00 the contrary, tbe f.lioe mars
is eafily brought la a granulatcd falt, by lIirring it wilh
a gla[s rod; and, when thlts granulated. it bas a great
deal more [urface ; ir di!1'olves more eaGly. and yields
il! tinélure to water io four hours time. Indeed one is
more expoftd tO the vapours of tbe folvcot, which woulrl
be dangerous, if Ihe opera!ionwcre to be often perforn!.
ed, without proper precautions.
.. When the bafoo, or Jiule veffe! cootainiDg t1ie
mixture of tbe impregnadon and fea·falt, is hemd, th"
liquor, which was of an orange.coloured red, becomes a
crimfon red; and, wheo alllhe phlegm of l'he [olvent is
evaporated, it acquires a beautiful emeraid colour. By
degrm it thickens, and turns of the colour of a maf.
of verdc&ris. It mun theo be carefully fiirred with die
glafs rod, io arder to granulate the falt, whith mun oot
be kept over the 6re till it be perfet\ly ~ry : becaufe you
run a riD, of lofiog irrecoverably the éolour you are–
feeking. You may be fure you ha\'e Ion it, ir by too
mueh 'hm the falt that was of a greco colour turo to ~
dirty yellow. If it be once brought to tbis flate, it will
continue without changing wheo eold: but if care be ta·
keo to reOlove it from the 6re while it is nm greco, you
will fee it gradually grolV pale, and become of a beaud·
fui rore·coloUl as it cools.
.. Mr Hellot feparates it from tbis ,eR'eI, and throw,
il into another containing difiilled raio-water : and thi~,
Cecond velfel he keeps io gentle di~enioD. till be obfervCJ
tba~ the pOll'der which falls to the bottom il perfe,qly
white·. If, after three or foul hours digefiing, this
powder fiill continues tinged witb a rafe colour, it is a
proof that water enou&h lI'in DOl added to dill'olvc all tb'e-
fall.