=POS′SET.= _Syn._ POSSETUM, L. Milk curdled with wine or any other
slightly acidulous liquor. It is usually sweetened with either sugar or
treacle, and is taken hot.
_Prep._ From new milk, 1/2 pint; sherry or marsala, 1 wine-glassful;
treacle, 1 or 2 tablespoonfuls, or q. s.; heat them together in a clean
saucepan until the milk coagulates. This is called ‘treacle posset’ or
‘molasses posset,’ and, taken on retiring to rest, is highly esteemed in
some parts of the country as a domestic remedy for colds. Lemon juice,
strong old ale, or even vinegar, is occasionally substituted for wine, and
powdered ginger or nutmeg added at will.
=POT METAL.= See COCK METAL.
=POT′ASH.= The ‘potash,’ or ‘potashes’ of commerce is an impure carbonate
of potassium, so named after the pots or vessels in which it was first
made. The ‘potash,’ or ‘potassa,’ of the chemist is the hydrate of a
peculiar metal, potassium, which is more particularly referred to below.
The word potash is vulgarly applied to the crude or commercial carbonate
of potassium. See CARBONATE OF POTASSIUM, &c.
Potash is now principally obtained from the following sources:——
1. From carnallite,[119] a hydrated double chloride of potassium and
magnesium, which occurs associated with other salts of potassium and
magnesium, as well as of sodium, in a bed of clay, at Stassfurth, near
Madgeburg, in Prussia.
[Footnote 119: Carnallite contains nearly a fourth of its weight of
potassium chloride.]
2. Feldspar and similar minerals.
3. Sea water, and the mother-liquor of salt works.
4. Native saltpetre.
5. The ashes of several plants.
6. The calcined residue of the molasses of beet-root sugar remaining after
distillation.
7. The seaweeds, as a by-product of the manufacture of iodine.
8. From the fleece of the sheep.[120]
[Footnote 120: Maumené and Rogelet state that a fleece weighing 9 lbs.
contains about 6 ounces of pure potash.]
The following is a process for obtaining alkali from seaweed, described in
the ‘Chemical News’ for Nov. 10th, 1876:——
At the chemical works at Aalbourg, in Jutland, Denmark, where about 30
tons of alkali are made per week by the ammonia process, Mr Theobald
Schmidt, the director of the manufactory, proposes to work, in conjunction
with this process, a method devised by himself of treating seaweed so as
to obtain iodine, potash, salts, and other marketable products therefrom.
In Denmark a very heavy duty is levied on the importation of common salt,
whilst enormous quantities of seaweed rich in iodine and potash can be
obtained at small cost in the neighbourhood of the works. Mr Schmidt’s
process is as follows:——After the seaweed is dried and burnt, a
concentrated solution of the ash is made and added to the liquor,
containing chlorides of sodium and calcium, left after the ammonia has
been recovered in the ammonia-soda process by boiling with lime. The
sulphates of potash, soda, and magnesia, contained in the ash of the
seaweed are thereby decomposed, and hydrated sulphate of lime and hydrated
magnesia are precipitated in a form which may be available for
paper-making, as ‘pearl-hardening.’ The last traces of sulphates are got
rid of by adding a small quantity of solution of chloride of barium. To
the clear solution nitrate of lead is now added, until all the iodine is
precipitated as iodide of lead, which is then separated by filtration and
treated for the production of iodine or iodides. After filtration the
liquid is boiled; nitrate of soda is added to convert the chloride of
potassium present into nitrate of potash. The latter is separated by
crystallisation. There remains a solution of common salt, containing
traces of ammonia from the previous soda operation, and a trace of
chloride of potassium. This solution is again treated by the ordinary
ammonia-soda process for the production of bicarbonate of soda and white
alkali. See CARBONATE OF POTASSIUM, &c.
=POTAS′SIUM.= K. The metallic base of potash. It was discovered, in 1807,
by Sir H. Davy, who obtained it by submitting moistened potassium hydrate,
under a film of naphtha, to the action of a powerful voltaic current. It
has since been procured by easier methods, of which the following,
invented by Brunner, is the best.
_Prep._ An intimate mixture of carbonate of potassium and charcoal is
prepared by calcining, in a covered iron pot, the crude tartar of
commerce; when cold, it is rubbed to powder, mixed with 1-10th part of
charcoal in small lumps, and quickly transferred into a retort of stout
hammered iron; the latter may be one of the iron bottles in which
quicksilver is imported, a short and somewhat wide iron tube having been
fitted to the aperture; the retort, thus charged, is placed upon its side,
in a furnace so constructed that the flame of a very strong fire,
preferably fed with dry wood, may wrap round it, and maintain every part
of it at a very high and uniform degree of heat. A copper receiver,
divided in the centre by a diaphragm, is next connected to the iron pipe,
and kept cool by the application of ice, whilst the receiver itself is
partly filled with mineral naphtha, to preserve the newly formed potassium
as it distils over. The arrangement of the apparatus being completed, the
fire is gradually raised until the requisite temperature, which is that of
full whiteness, is reached, when decomposition of the alkali by the
charcoal commences, carbonic acid gas is abundantly disengaged, and
potassium distils over, and falls in large drops into the liquid. To
render the product absolutely pure, it is redistilled in an iron or
green-glass retort, into which some naphtha has been put, that its vapour
may expel the air, and prevent the oxidation of the metal. The pieces of
charcoal are introduced for the purpose of absorbing the melted carbonate
of potassium and preventing its separation from the finely divided
carbonaceous matter. _Prod._ 3% to 4% of the weight of tartar acted on; 1
lb. yielded 280 gr.
_Prop., &c._ Pure potassium is a brilliant white metal, with a high
lustre; at the common temperature of the air it is soft, and may be easily
cut with a knife, but at 32° Fahr. it is brittle and crystalline; it melts
completely at 136° Fahr., and in close vessels distils unaltered at a low
red heat. Sp. gr. ·865. Its most remarkable property is its affinity for
oxygen, which is so great that it takes it from most other substances
containing it. Exposed to the air, its surface is instantly tarnished, and
quickly becomes covered with a crust of oxide or hydrate. It inflames
spontaneously when thrown on water, and burns with a beautiful purple or
purple-red flame, yielding a pure alkaline solution. It can only be
preserved in naphtha, rock oil, or some other fluid hydrocarbon.
The salts of potassium are all soluble in water, the tartrate, periodate,
and fluosilicate being the least so; they are usually colourless, unless
the acid be coloured, crystallise readily, and form numerous double
compounds. They can be recognised as follows:——
Sulphuretted hydrogen, sulphide of ammonium, and carbonate of ammonium, do
not affect them. A solution of tartaric acid, added in excess, to
moderately strong neutral or alkaline solutions of potassium salts, gives
a quickly subsiding, gritty or crystalline, white precipitate, which is
redissolved on heating the liquid, and again separates as it cools; and is
also soluble in aqueous solutions containing free alkali, or free mineral
acids. Platinic chloride produces, in neutral and acid solutions, a yellow
crystalline precipitate. Alkaline solutions require to be first slightly
acidulated with hydrochloric acid. The separation of the precipitate here,
as well as that produced by tartaric acid, is promoted by violent
agitation and friction against the sides of the vessel, and the delicacy
of both is increased by the addition of some alcohol. When converted into
carbonate by igniting with excess of carbonate of ammonium and alcohol,
and treated with sulphuretted hydrogen solution and nitro-prusside of
sodium, gives a splendid violet colour, turning through red to green on
standing.
Potassium salts give with sodium periodate and hydro-fluosilicic acid
white precipitates soluble in much water.
Heated in the inner flame of the blow-pipe on platinum wire, they impart a
violet coloration, masked, however, by a mere trace of sodium salts.
=Potassium, Acetate of.= KC_{2}H_{3}O_{2}. _Syn._ ACETATE OF POTASH,
POTASSIC ACETATE; POTASSÆ ACETAS (B. P., Ph. L., E., D.). _Prep._ (Ph. L.)
Acetic acid, 26 fl. oz.; distilled water, 12 fl. oz.; mix, and add,
gradually, carbonate of potassium, 1 lb., or q. s. to saturate the acid;
next, filter the solution, and evaporate it by the heat of a sand bath,
gradually applied, until the salt is dried.
_Prop., &c._ Acetate of potassium, prepared as above, occurs in shining
white masses, having a foliated soft texture, a slight but peculiar odour,
and a warm sharp taste; it deliquesces in the air; dissolves in rather
less than its own weight of water, and in about twice its weight of
alcohol; and by exposure to a red heat is converted into pure carbonate of
potassium. In trade it is preserved in well-corked and sealed bottles.
_Pur._ It is entirely soluble in water, and in rectified spirit. These
solutions neither affect litmus nor turmeric, nor are they disturbed by
either chloride of barium or nitrate of silver; but if from a stronger
solution anything is thrown down by nitrate of silver, the same is again
dissolved on the addition of water or dilute nitric acid. Sulphuric acid
being added, the vapour of acetic acid is evolved. 100 gr. of this salt,
digested in sulphuric acid, the solution evaporated, and the residuum
dried at a high temperature, furnish 88·8 gr. of sulphate of potassium.
_Uses, &c._ Acetate of potassium has been found useful in dropsies,
febrile affections, jaundice, scurvy, calculus, and several chronic skin
diseases. During its exhibition the urine becomes at first neutral, and
then alkaline, owing to the salt being converted into carbonate of
potassium in the system.——_Dose._ As a diaphoretic and antiscorbutic, 15
to 20 gr.; as a diuretic, 20 to 60 gr.; as an aperient, 2 to 3 dr.; in
each case dissolved in some bland liquid, or in the infusion of some mild
vegetable bitter.
=Potassium Antimoniates.= The normal potassic antimoniate may be obtained
by heating, in an earthen crucible, 1 part of metallic antimony with 4
parts of nitrate of potash. The mass so obtained is reduced to powder, and
afterwards washed with warm water to remove the excess of potash and
potassic nitrite. The residue must be boiled in water for an hour or two;
the insoluble anhydrous antimoniate is thus converted into a soluble
hydrated modification (K_{2}Sb_{2}O_{6},5H_{2}O.) The insoluble residue
now consists chiefly of acid antimoniate of potassium. The normal salts
possess the property of readily dissolving the acid antimoniate, which is
precipitated when such a solution is mixed with any neutral salt of one of
the alkalies. The normal antimoniate does not crystallise, and has an
alkaline reaction.
Acid antimoniate of potassium (K_{2}Sb_{4}O_{11}.) may be procured by
passing a stream of carbonic anhydride through a solution of the normal
antimoniate.
Acid metantimoniate of potash, or hydro-potassic metantimoniate is
prepared as follows:——Potassic antimoniate is first formed by deflagrating
antimony with nitre, the residue being washed and boiled as described
above, so as to bring the whole of the normal antimoniate into solution;
the resulting liquid is filtered, and evaporated to a syrup consistence in
a silver dish, fragments of caustic potash are then added, and the
evaporation is continued until a drop of liquid placed upon a cold slip of
glass begins to crystallise; it is then allowed to cool and the alkaline
supernatant liquid is poured off the crystals, which are allowed to drain
upon a porous tile. This salt is employed as a test for sodium.
=Potassium, Arseniate of.= KH_{2}AsO_{4}. _Syn._ ARSENIATE OF POTASSA,
MONOPOTASSIC ARSENIATE, POTASSIUM DIHYDRIC ARSENIATE; POTASSÆ BINARSENIAS,
L. _Prep._ Take of arsenious acid (white arsenic) and nitrate of
potassium, of each, in powder, 1 part; heat the mixture to dull redness in
a glass flask, until it fuses and red vapours cease to be evolved;
dissolve the residuum, when cold, in boiling distilled water, 50 parts;
concentrate the solution by evaporation, and set it aside to crystallise.
_Prop., &c._ This salt forms large crystals, which are permanent in dry
air, soluble in about 4-1/2 parts of water, and insoluble in alcohol. It
is reputed tonic, alterative, and antiperiodic.——_Dose_, 1/16 to 1/8 gr.
dissolved in sweetened water. It is also used to form a resist-paste in
calico printing, and in the manufacture of cobalt blue.
=Potassium, Borate of.= K_{4}B_{4}O_{8}. _Syn._ POTASSÆ BORAS, L. _Prep._
From dry carbonate of potassium and dry boracic acids, equal parts,
reduced to powder, and heated to redness in a covered crucible; the
sublimed mass, when cold, being dissolved in boiling water, and the
filtered solution concentrated by evaporation, and then set aside to
crystallise; or at once completely evaporated to dryness.——_Dose_, 1 to 6
gr.; in calculi, &c.
=Potassium, Borotartrate of.= _Syn._ POTASSÆ BOROTARTRAS, CREMOR TARTARI
SOLUBILIS, L.; CRÈME DE TARTRE SOLUBLE, Fr. _Prep._ (P. Cod.) Crystallised
boracic acid, 1 part; bitartrate of potassium, 4 parts; water, 24 parts;
dissolve, by the aid of heat, in a silver basin, and, constantly stirring,
evaporate the resulting solution, either to dryness, and then powder it,
or merely to a syrupy consistence, when it may be spread upon plates, and
dried in scales, by the heat of a stove. It must afterwards be preserved
from the air.
_Prop., &c._ A white, deliquescent powder, freely soluble in water. It has
been used as a solvent for lithic calculi, and in gout, &c.——_Dose_, 15 to
30 gr. In doses of 2 to 3 dr. it is laxative, and is very popular as such
on the Continent.
=Potassium, Bromide of.= KBr. _Syn._ POTASSII BROMIDUM (B. P.). _Prep._
Exactly as the iodide, which it resembles in its character, only being
somewhat less soluble in water and more in alcohol. Employed in similar
cases and given in similar doses to the iodide.
=Potassium, Carbonate of.= K_{2}CO_{3}. _Syn._ CARBONATE OF POTASSA,
SUBCARBONATE OF POTASSA, SALT OF TARTAR; POTASSÆ CARBONAS (B. P., Ph. L.,
E., D.). Impure or crude carbonate of potassium is chiefly imported from
America and Russia, and is obtained by lixiviating wood ashes, and
evaporating the solution to dryness. The mass is then transferred into
iron pots, and is kept in a state of fusion for several hours, until it
becomes quiescent, when the heat is withdrawn, and the whole is left to
cool. It is next broken up and packed in air-tight barrels, and in this
state constitutes the ‘potashes’ or ‘potash’ of commerce. Another method
is to transfer the black salts, or product of the first evaporation, from
the kettles to a large oven or furnace, so constructed that the flame is
made to play over the alkaline mass, which is kept constantly stirred by
means of an iron rod. The ignition is continued until the impurities are
burned out, and the mass changes from a blackish tint to a dirty or bluish
white. The whole is next allowed to cool, and is then broken into
fragments, and packed in casks as before. It now constitutes ‘pearlash.’
When pearlash is dissolved in cold distilled water, the solution
depurated, filtered and crystallised, or simply evaporated to dryness, it
forms ‘refined ashes,’ or carbonate of potash sufficiently pure for most
pharmaceutical and technical purposes. The granulated carbonate of potash,
salt of tartar, or prepared kali, of the shops, is simply refined ashes
which, during the evaporation, and more especially towards the conclusion
of the desiccation, has been assiduously stirred, so that it may form
small white granulations, instead of adhering together to form an
amorphous solid mass. In this state it constitutes the ordinary or
carbonate of potassa of the Pharmacopœias. Ordinary potash or pearlash may
be refined as follows:——Raw potash, 10 parts, is dissolved in cold water,
6 parts, and the solution is allowed to remain for 24 hours, in a cool
place; it is then filtered, and somewhat concentrated by evaporation,
crystallisation being prevented by continually stirring the mass until the
whole is nearly cold; it is next decanted into a strainer, and the
mother-liquor allowed to drip off; the residuum is evaporated to dryness
at a gentle heat, and redissolved in an equal quantity of cold distilled
water; the new solution, after filtration, is again evaporated to dryness.
The product is quite free from potassium sulphate, and is nearly free from
both potassium chloride and silicates.
=Potassium, Pure Carbonate of.= CARBONATE OF POTASSA (POTASSÆ CARBONAS
PURUM——Ph. E. & D., and Ph. L., 1836).——(Ph. L., 1836.) From bicarbonate
of potassium, in crystals, heated to redness in a crucible.
(Ph. E.) As the last. Or, more cheaply, by dissolving bitartrate of
potassium in thirty parts of boiling water, separating and washing the
crystals which form on cooling, heating them in a loosely covered crucible
to redness as long as fumes are discharged, breaking down the mass, and
roasting it in an oven for two hours, with occasional stirring;
lixiviating the product with (cold) distilled water, filtering the
solution thus obtained, evaporating it to dryness, granulating the salt
towards the close by brisk agitation; and, lastly, heating the granular
salt thus obtained nearly to redness.
(Ph. D.) Bitartrate of potassium, 2 lbs., is exposed to a red heat in an
iron crucible, as before; the powdered calcined mass is boiled for 20
minutes in water, 1 quart, the solution filtered, and the filtrate washed
with water, 1 pint, to which ammonium sesquicarbonate, 1/2 oz., has been
added; the mixed and filtered liquors are evaporated to dryness, and, a
low red heat having been applied, the residuum is rapidly reduced to
powder in a warm mortar, and at once enclosed in (dry and) well-stoppered
bottles.
_Prop._ These are well known. It exhibits most of the properties of
hydrate of potassium, but in a vastly less degree. It is very
deliquescent, effervesces with acids, exhibits a marked alkaline reaction
with test paper, is insoluble in alcohol, but dissolves in less than its
own weight of water, its affinity for the last being so great that it
takes it from alcoholic mixtures.
_Pur., &c._ Carbonate of potassium frequently contains an undue quantity
of water, as well as silicic acid, sulphates, and chlorides. The water may
be detected by the loss of weight the salt suffers when heated; the
silica, by adding to it hydrochloric acid in excess, evaporating to
dryness, and igniting the residuum, by which this contamination is
rendered insoluble; the sulphates and chlorides may be detected by adding
nitric acid in excess, and testing the liquid with nitrate of silver and
chloride of barium. If the former produces a white precipitate, a chloride
is present; and if the latter does the same, the contamination is a
sulphate. Carbonate of potassium deliquesces in the air, and is almost
entirely dissolved by water; in an open vessel it spontaneously liquefies.
It changes the colour of turmeric brown. Supersaturated with nitric acid,
neither carbonate of sodium nor chloride of barium throws down anything,
and nitrate of silver very little. 100 gr. lose 16 gr. of water by a
strong red heat; and the same weight loses 26·3 gr. of carbonate anhydride
when placed in contact with dilute sulphuric acid.
=Potassium, Bicarbonate of.= KHCO_{3}. _Syn._ POTASSIUM HYDROGEN
CARBONATE, BICARBONATE OF POTASSA; POTASSÆ BICARBONAS (B. P., Ph. L., E.,
& D.). _Prep._ 1. (Ph. L. 1836.) Carbonate of potassium, 6 lbs.; distilled
water, 1 gall.; dissolve, and pass carbonic anhydride (from chalk and
sulphuric acid diluted with water) through the solution to saturation;
apply a gentle heat, so that whatever crystals have been formed may be
dissolved, and set aside the solution that crystals may again form;
lastly, the liquid being poured off, dry them.
2. (Ph. D.) Carbonic anhydride, obtained by the action of dilute
hydrochloric acid on chalk (the latter contained in a perforated bottle
immersed in a vessel containing the acid), is passed, by means of glass
tubes connected by vulcanised india rubber, to the bottom of a bottle
containing a solution of carbonate of potassium, 1 part, in water, 2-1/2
parts; as soon as the air is expelled from the apparatus the corks through
which the tubes pass are rendered air-tight, and the process left to
itself for a week; the crystals thus obtained are then shaken with twice
their bulk of cold water, drained, and dried on bibulous paper, by simple
exposure to the air. From the mother-liquor, filtered, and concentrated to
one half, at a heat not exceeding 110° Fahr., more crystals may be
obtained. The tube immersed in the solution of carbonate of potassium will
have to be occasionally cleared of the crystals with which it is liable to
become choked, else the process will be suspended.
3. (Ph. B.) The same.
4. (Apothecaries’ Hall, London.) Potassium carbonate, 100 lbs.; distilled
water, 17 galls.; dissolve, and saturate the solution with carbonic
anhydride, as in No. 1, when 35 to 40 lbs. of crystals of bicarbonate of
potassium may be obtained; next dissolve carbonate of potassium, 50 lbs.,
in the mother-liquor, and add enough water to make the whole a second time
equal to 17 galls.; the remaining part of the operation is then to be
performed as before. This plan may be repeated again and again, for some
time, provided the carbonate used is sufficiently pure.
5. (Ph. E.) Take of carbonate of potassium, 6 oz.; sesquicarbonate of
ammonium, 3-1/2 oz.; triturate them together, and, when reduced to a very
fine powder and perfectly mixed, make them into a stiff paste with a very
little water; dry this, very carefully, at a heat not higher than 140°
Fahr., until a fine powder, perfectly devoid of ammoniacal odour, be
obtained, occasionally triturating the mass towards the end of the
process.
6. (Commercial.) From carbonate of potassium, in powder, made into a paste
with water, and exposed for some time on shallow trays, in a chamber
filled with an atmosphere of carbonic anhydride, generated by the
combustion of either coke or charcoal, and purified by being forced
through a cistern of cold water; the resulting salt is next dissolved in
the least possible quantity of water at the temperature of 120° Fahr., and
the solution filtered and crystallised.
_Prop._ It is soluble in 4 times its weight of water at 60° Fahr.; is
fixed in the air, but loses carbonic acid below the temperature of a
carbonate at a red heat. It possesses the general alkaline properties of
carbonate of potassium, but in an inferior degree, having only a slightly
alkaline taste, and, when absolutely pure, not affecting the colour of
turmeric.
_Pur._ In a solution of pure bicarbonate of potassium a solution of
mercuric chloride merely causes an opalescence, or very slight white
precipitate; if it contains carbonate, a brick-coloured precipitate is
thrown down. From 100 gr. of the pure crystals of bicarbonate, 30·7 gr. of
water and carbonic acid are expelled at a red heat. In other respects it
may be tested like the carbonate.
_Uses, &c._ Bicarbonate of potassium is the most agreeable of all the
salts of potassium, and is much used as an antacid or absorbent, and for
making effervescing saline draughts. It has also been successfully
employed in rheumatism, scurvy, gout, dyspepsia, and various other
diseases in which the use of potassium is indicated. The dose is from 10
gr. to 1/2 dr.
20 gr. bicarbonate, in crystals,
---------------------\/---------------------
are equivalent to
---------------------/\---------------------
14 gr. of crystallised nitric acid,
15 gr. of crystallised tartaric acid, and
1/2 oz. of lemon juice.
=Potassium, Chlorate of.= KClO_{3}. _Syn._ CHLORATE OF POTASH; POTASSÆ
CHLORAS (B. P., Ph. L. & D.), L. _Prep._ 1. Chlorine gas is conducted by a
wide tube into a moderately strong and warm solution of hydrate or
carbonate of potassium, until the absorption of the gas ceases and the
alkali is completely neutralised; the liquid is then kept at the boiling
temperature for a few minutes, after which it is gently evaporated (if
necessary) until a pellicle forms on the surface, and is next set aside,
so as to cool very slowly; the crystals, thus obtained, are drained and
carefully washed on a filter, with ice-cold water, and are purified by
re-solution and re-crystallisation. The product is chlorate of potassium.
The mother-liquor, which contains much chloride of potassium mixed with
some chlorate, is either evaporated for more crystals (which are, however,
less pure than the first crop) or is preserved for a future operation.
_Obs._ The product of the above process is small, varying from 10 to 45%
of the weight of the potassium consumed in it, according to the skill with
which it is conducted; this apparent loss of potassium arises from a large
portion of it being converted into chloride, a salt of comparatively
little value. The following processes have been devised principally with
the view of preventing this waste, or of employing a cheaper salt of
potassium than the carbonate:——
2. (Ph. B.) Mix slaked lime, 53 oz., with carbonate of potash, 20 oz., and
triturate them with a few ounces of distilled water, so as to make the
mixture slightly moist. Place oxide of manganese, 80 oz., in a large
retort or flask, and having poured upon it hydrochloric acid, 24 pints,
diluted with 6 pints of water, apply a gentle sand heat, and conduct the
chlorine as it comes over, first through a bottle containing 6 oz. of
water, and then into a large carboy containing the mixture of carbonate of
potash and slaked lime. When the whole of the chlorine has come over
remove the contents of the carboy and boil them for 20 minutes with 7
pints of distilled water; filter and evaporate till a film forms on the
surface, and set aside to cool and crystallise.
The crystals thus obtained are to be purified by dissolving them in 3
times their weight of boiling distilled water, and again allowing the
solution to crystallise.——_Dose_, 10 gr. to 30 gr.
3. A solution of chloride of lime is precipitated with a solution of
carbonate of potassium, and the liquid, after filtration, saturated with
chlorine gas; it is then evaporated and crystallised as before. Dr Ure has
suggested the substitution of sulphate of potassium for the carbonate, by
which the process would be rendered very inexpensive.
4. Carbonate of potassium, 69 parts of the dry or 82 parts of the
granulated, hydrate of calcium, 37 parts (dry fresh slaked lime), both in
powder, are mixed together, and exposed to the action of chlorine gas, to
saturation (the gas is absorbed with great rapidity, the temperature rises
above 212° Fahr., and water is freely evolved); the heat, with free
exposure, is then maintained at 212° for a few minutes (to remove some
trace of ‘hypochlorite’), the residuum, consisting of chlorate of
potassium and chloride of calcium, is treated with hot water, and the
chlorate of potassium crystallised out of the resulting solution, as
before. This process, which is an excellent one (the loss of potassium
being for the most part avoided), has been modified and improved by
various authorities, as will be seen below.
5. A solution of chloride of lime (18° to 20° Baumé) is heated in a leaden
or cast-iron vessel, and sufficient of a salt of potassium added to raise
the density of the liquid 3 or 4 hydrometer degrees; the solution is then
quickly, but carefully, concentrated until the gravity rises to 30° or 31°
Baumé, when it is set aside to crystallise. A good and economical process.
6. Chloride of potassium, 76 parts, and fresh calcium hydrate, 222 parts,
are reduced to a thin paste with water, q. s., and a stream of chlorine
gas passed through the mixture, to saturation; chloride of calcium and
chlorate of potassium are formed; the last is then removed by solution in
boiling water, and is crystallised as before. This process, which has
received the approval and recommendation of Liebig, has long been
practised in Germany, and was originally introduced to this country by Dr
Wagenmann. The product is very large, and of excellent quality.
_Prop._ White, inodorous, four-or six-sided pearly scales, soluble in
about 20 parts of cold and 2-1/2 parts of boiling water; in taste it
resembles nitre, but is somewhat more austere; at about 450° Fahr. it
undergoes the igneous fusion, and on increasing the heat almost to redness
effervescence ensues, and fully 39% of pure oxygen gas is given off,
whilst the salt becomes changed into chloride of potassium. When mixed
with inflammable substances and triturated, heated, or subjected to a
smart blow or strong pressure, or moistened with a strong acid, it
explodes with great violence.
_Pur., Tests, &c._ The usual impurity of this salt is chloride of
potassium, arising from careless or imperfect manipulation. When this is
present, a solution of nitrate of silver gives a curdy white precipitate,
soluble in ammonia; whereas a solution of the pure chlorate remains clear.
_Uses._ Chlorate of potassium is principally used in the manufacture of
lucifer matches, fireworks, oxygen gas, &c., and as an oxidising agent in
calico printing. It was formerly used to fill percussion caps, but was
abandoned for fulminating mercury, on account of its disposition to rust
the nipples of the guns. As a medicine it is stimulant and diuretic. It
has been given in dropsy, syphilis, scurvy, cholera, typhus, and other
depressing affections. It gives a fine artificial colour to the blood.
(Stevens.)——_Dose_, 5 to 15 gr., in solution, twice or thrice a day.
_Concluding Remarks._——Formerly, chlorate of potassium was a salt which
was made only on the small scale, and chiefly used in experimental
chemistry; now it is in considerable demand, and forms an important
article of chemical manufacture. The latter has hence, of late years,
received considerable attention and improvement in the leading
laboratories of Europe. The chlorate requires to be handled with great
care. It should never be kept in admixture with any inflammable substance,
more especially with sulphur, phosphorus, or the sulphides, as these
compounds are exploded by the most trivial causes, and, not unfrequently,
explode spontaneously.
=Potassium, Chloride of.= KCl. _Syn._ CHLORIDE OF POTASSA. _Prep._ The
chloride of potassium of commerce is usually a secondary product in the
manufacture of chlorate of potassium and other substances. The
mother-liquor of the former is evaporated to dryness and heated to dull
redness, the calcined mass is then dissolved in water, the solution
purified by defecation and evaporated down for crystals.
It can also be well prepared by neutralising boiling solution of carbonate
of potassium by dilute hydrochloric acid, evaporating down, and
crystallising.
_Prop., &c._ It closely resembles culinary salt in appearance; is
anhydrous; dissolves in about 4 parts of cold and 2 of boiling water; has
a slightly bitter, saline taste; fuses at a red heat; and is volatilised
at a very high temperature. As a medicine it is diuretic and aperient. It
was formerly in high repute as a resolvent and antiscorbutic, and,
particularly, as a remedy for intermittents. It is now seldom
used.——_Dose_, 10 gr. to 1/2 dr., or more.
=Potassium, Chromate of.= K_{2}CrO_{4}. _Syn._ CHROMATE OF POTASSA,
NEUTRAL CHROMATE OF P., MONOCHROMATE OF P., YELLOW C. OF P., SALT OF
CHROME; POTASSÆ CHROMAS, P. C. FLAVA, L. This salt is only prepared on the
large scale. Its source is ‘CHROME ORE,’ a natural octahedral chromate of
iron, found in various parts of Europe and America. For medicinal purposes
the commercial chromate is purified by solution in hot water, filtration,
and recrystallisation.
_Prep._ 1. The ore, previously assayed to determine its richness, and
freed as much as possible from its gangue, is ground to powder in a mill,
and mixed with a quantity of coarsely powdered nitre rather less than that
of the oxide of chromium which it contains; this mixture is exposed, for
several hours, to a powerful heat on the hearth of a reverberatory
furnace, during which time it is frequently stirred up with iron rods; the
calcined mass is next raked out and lixiviated with hot water, and the
resulting yellow-coloured solution evaporated briskly over a naked fire,
or by the heat of high-pressure steam; chromate of potassium falls, under
the form of a granular yellow salt, which is removed from time to time
with a ladle, and thrown into a wooden vessel, furnished with a bottom
full of holes (draining box), where it is left to drain and dry. In this
state it forms the chromate of potassium of commerce. By a second solution
and recrystallisation, it may be obtained in large and regular crystals.
The next process has for its object the employment of a cheaper salt of
potassa than the nitrate.
2. (Swindell & Co. Patent dated Nov., 1850.) A mixture of pulverised
chrome ore and chloride of potassium is exposed to a full red heat, on the
hearth of a reverberatory furnace, with occasional stirring for some time,
when steam at a very elevated temperature is made to act on it until the
conversion is complete, known by assaying a portion of the mass; the
chromate is then dissolved out of the residuum, as before. Common salt or
hydrate of calcium may be substituted for chloride of potassium, when the
chromates of sodium or calcium are respectively produced.
3. On the small scale this salt may be prepared from the bichromate by
neutralising it with hydrate of potassium.
_Prop._ Yellow; tastes cool, bitter, and disagreeable; soluble in 2 parts
of water at 60° Fahr.; the crystals are efflorescent.
_Pur._ The salt of commerce is frequently contaminated with large
quantities of sulphate or chlorate of potassium. To detect these, M.
Zueber adds tartaric acid, dissolved in 50 parts of water, to a like
solution of the sample. As soon as the decomposition is complete, and the
colour verges towards the green, the supernatant liquor should afford no
precipitate with solutions of the nitrates of silver and barium, whence
the absence of chlorides and sulphates may be respectively inferred. The
proportions are, 8 parts of tartaric acid to 1 part of the chromate. If
saltpetre is the adulterating ingredient, the sample deflagrates when
thrown upon burning coals.
_Assay._ 1. A solution of 50 gr. of the salt is treated with a solution of
nitrate of barium, the precipitate digested in nitric acid, and the
insoluble portion (sulphate of barium) washed, dried, and weighed. 117 gr.
of this substance are equivalent to 89 gr. of sulphate of potassium.
2. The nitric solution, with the washings (see _above_), is treated with a
solution of nitrate of silver, and the precipitate of chloride carefully
collected, washed, dried, ignited, and weighed. 144 gr. of chloride of
silver represent 76 gr. of chloride of potassium.
3. The nitric solution, with the washing (see _above_), after having any
remaining barium thrown down by adding dilute sulphuric acid, in slight
excess, is treated with ammonia, and the resulting precipitate of chromic
oxide collected on a filter, washed, dried, carefully ignited in a silver,
platinum, or porcelain crucible, and weighed. 40 gr. of this oxide
represent 100 gr. of pure chromate of potassium. Any deficiency consists
of impurities or adulterants.
_Uses._ Chromate of potassium is used in dyeing, bleaching, the
manufacture of chromic acid, bichromate of potassium, &c. It is the common
source of nearly all the other compounds of chromium. It is reputed
alterative in doses of 1/12 to 1/2 gr.; and is emetic in doses of 1 to 4
gr. A solution in 8 parts of water is occasionally used to destroy fungus;
1 in 30 to 40 parts of water is also used as an antiseptic and desiccant.
_Concluding Remarks._——The first process is undoubtedly the best, when
expense is not an object. To reduce this, a mixture of ‘potash’ or
‘pearlash,’ with about 1/2 of its weight of nitre, or 1-5th part of its
weight of peroxide of manganese, may be substituted without much
inconvenience. The assay of the chrome ore, alluded to above, may be made
by reducing 100 gr. of it to powder, mixing it with twice its weight of
powdered nitre, and a little hydrate of calcium, and subjecting the
mixture to a strong red heat for 3 or 4 hours; the calcined mass may then
be exhausted with boiling water, and the resulting solution, after
precipitation with dilute sulphuric acid, in slight excess, and
filtration, may be treated with rectified spirit, when its chromium may be
thrown down by the addition of ammonia. (See _above_.) In the conversion
of chrome ore into chromate of potassium care should, in all cases, be
taken that the proportion of nitre or alkali should be slightly less than
what is absolutely required to saturate the ore, as the production of a
neutral salt is thereby ensured; for should not the whole of the chromate
be decomposed by the first calcination, it may easily be roasted a second
time with fresh alkali, should the remaining quantity he thought worth the
trouble. The nature of the furnace to be employed in the conversion is not
of any great importance, so long as carbonaceous matters from the fire are
entirely excluded, and the required temperature is attainable.
=Potassium, Bichromate of.= K_{2}Cr_{2}O_{7}, or K_{2}CrO_{4},CrO_{3}.
_Syn._ BICHROMATE OF POTASSA, RED CHROMATE OF POTASH, ACID C. OF P.;
POTASSÆ BICHROMAS, L. _Prep._ 1. To a concentrated solution of yellow
chromate of potassium, sulphuric acid, or, better, acetic acid, is added
in quantity equal to one half that required for the entire decomposition
of the salt; the liquid is then concentrated by evaporation and slowly
cooled, so that crystals may form.
2. (Jacquelain.) Chrome ore, finely ground and sifted, is mixed with
chalk; the mixture is spread on a thin layer on the hearth of a
reverberatory furnace, and heated to bright redness, with repeated
stirring, for 9 or 10 hours. The yellowish-green product consists
essentially of neutral chromate of calcium, mixed with ferric oxide. It is
ground and stirred up with hot water, and sulphuric acid is added till a
slight acid reaction becomes apparent, a sign that the neutral chromate
has been converted into bichromate. Chalk is now stirred in to precipitate
the ferric sulphate, and after a while the clear solution is run off into
another vessel, where it is treated with carbonate of potassium, which
precipitates the lime and leaves bichromate of potassium in solution. The
solution is then evaporated to the crystallising point. This process, when
carried out on a large scale, is very economical.
_Prop., &c._ It forms very beautiful square tables, or flat four-sided
prismatic crystals; permanent in the air; soluble in 10 parts of water at
60°, and in less than 3 parts at 212° Fahr.; it has a metallic, bitter
taste, and is poisonous. It is chiefly used in dyeing and bleaching, and
as a source of chromic acid. The tests, &c., are the same as for the
yellow chromate.
=Potassium, Citrate of.= K_{3}C_{6}H_{5}O_{7}. _Syn._ POTASSÆ CITRAS, L.
_Prep._ From a solution of citric acid neutralised with carbonate of
potassium, evaporated, and granulated, or crystallised; very deliquescent.
Or, extemporaneously, in the form of solution, by adding carbonate or
bicarbonate of potassium to lemon juice, as in the common effervescing
draught. (Ph. B.) The same.
=Potassium, Cyanate of.= KCyO, or KCNO. _Prep._ 1. By roasting, at a red
heat, dry ferrocyanide of potassium, in fine powder, upon an iron plate,
constantly stirring it until it becomes fused into one mass, which must be
reduced to fine powder and digested in boiling alcohol, from which
crystals of the cyanate will be deposited as the solution cools.
2. (Liebig.) A mixture of ferrocyanide of potassium, with half its weight
of peroxide of manganese, may also be used to produce this salt, as the
last; the compound should be kindled by a red-hot body, and allowed to
smoulder away, after which it may be treated with alcohol, as before.
3. A mixture of ferrocyanide of potassium and litharge is heated as
before, and dissolved out by alcohol, and crystallised.
_Prop._ Crystallisable colourless or white salt, readily soluble in
alcohol and water, but readily decomposed when moist into bicarbonate of
potassium and ammonia, or in solution into the carbonate of potassium and
ammonium.
This salt is poisonous. The cyanates of silver, lead, and many other
metals may be made by adding a solution of cyanate of potassium to another
of a neutral salt of the base.
=Potassium, Cyanide of.= KCN, or KCy. _Syn._ CYANIDE OF POTASH, CYANURET
OF POTASSIUM; POTASSII CYANIDUM, P. CYANURETUM, L.
_Prep._ 1. (MEDICINAL CYANIDE OF POTASSIUM.)——_a._ A solution of pure
hydrate of potassium, 2 parts, in highly rectified spirit, 7 parts, is
placed in a receiver furnished with a safety tube, and surrounded with
bruised ice; the beak of a tubulated retort, containing ferrocyanide of
potassium, in powder, 4 parts, is then adapted to it in such a manner that
any gas or vapour evolved in the retort must traverse the solution in the
receiver; the arrangement being complete, sulphuric acid, 3 parts, diluted
with an equal weight of water, and allowed to cool, is cautiously poured
into the retort, and the distillation conducted very slowly, a very gentle
heat only being applied, as circumstances may direct; as soon as the force
of ebullition in the retort has subsided, the distillation is complete,
and the connection between the retort and receiver is broken; the contents
of the receiver, now transformed into a mixture of a crystalline
precipitate of cyanide of potassium, and an alcoholic solution of
undecomposed hydrate of potassium, is carefully thrown on a filter, and
the precipitate, after the mother-liquor has drained off, very cautiously
washed with ice-cold and highly rectified spirit, and then drained,
pressed, and dried on the same filter. The product is chemically pure, and
equal to fully 10% of the ferrocyanide employed. This is a modification of
what is commonly known as ‘Wigger’s process.’
_b._ Expose well-dried and powdered ferrocyanide of potassium to a
moderate red heat, in a close vessel; when cold, powder the fused mass,
place it in a funnel, moisten it with a little alcohol, and wash it with
cold water; evaporate the solution thus formed to dryness, expose it to a
dull red heat in a porcelain dish, cool, powder, and digest it in boiling
rectified spirit; as the spirit cools, crystals of cyanide of potassium,
nearly pure, will be deposited. The alcohol employed in both this and the
preceding process may be recovered by distillation from calcined sulphate
of iron.
2. (CRUDE or COMMERCIAL CYANIDE——Liebig.) Commercial ferrocyanide of
potassium, 8 parts, rendered anhydrous by gently heating it on an iron
plate, is intimately mixed with dry carbonate of potassium, 3 parts; this
mixture is thrown into a red-hot earthen crucible, and kept in a state of
fusion, with occasional stirring, until gas ceases to be evolved, and the
fluid portion of the mass becomes colourless; the crucible is then left at
rest for a few minutes, to allow its contents to settle, after which the
clear portion is poured from the heavy black sediment at the bottom upon a
clean marble slab, and the mass, whilst yet warm, broken up, and placed in
well-closed bottles.
_Obs._ A cheap and excellent process. The product is said to contain about
1-8th part of cyanate of potassium, and, though not sufficiently pure for
employment in medicine as potassium cyanide, is admirably adapted for the
various technical applications of this substance, as in electro-plating,
electro-gilding, photography, &c. It may also be advantageously
substituted for the ferrocyanide in the preparation of hydrocyanic acid by
the distillation of that substance along with dilute sulphuric acid.
_Prop., &c._ When pure, this salt is colourless and odourless; it forms
cubic or octahedral crystals, which are anhydrous; it is freely soluble in
water and in boiling alcohol, but most of it separates from the latter as
the solution cools; it is fusible; and undergoes no change, even at a full
red heat, in close vessels; it exhibits an alkaline reaction; when exposed
to the atmosphere, it absorbs moisture, and acquires the smell of
hydrocyanic acid. If it effervesces with acids, it contains carbonate of
potassium, and if it be yellow it contains iron. It is employed in
chemical analysis, and for the preparation of hydrocyanic acid; cyanide of
sodium may be made in the same way. The dose is 1/12 to 1/4 gr., in
solution; in the usual cases in which the administration of hydrocyanic
acid is indicated.——_Antidotes._ The same as for hydrocyanic acid.
=Potassium, Ferricyanide of.= K_{3}FeCy_{6}, or K_{3},FeC_{6}N_{6}. _Syn._
FERRIDCYANIDE OF POTASSIUM, FERRICYANURET OF P., RED PRUSSIATE OF POTASH;
POTASSII FERRICYANIDUM, P. PRUSSIAS RUBRUM, L. This important and
beautiful salt was discovered by L. Gmelin. At first it was merely
regarded as a chemical curiosity, but it is now extensively employed in
dyeing, calico printing, assaying, &c.
_Prep._ 1. Chlorine gas, prepared in the ordinary manner, is slowly passed
into a cold solution of ferrocyanide of potassium, 1 part, in water, 10
parts, with constant agitation, until the liquid appears of a deep
reddish-green colour, or of a fine red colour by transmitted light, and
ceases to give a blue precipitate, or even a blue tinge, to a solution of
ferric chloride, an excess of chlorine being carefully avoided; the
liquor is next evaporated by the heat of steam or boiling water, until
a pellicle forms upon the surface, when it is filtered, and set aside
to cool; the crystals are afterwards purified by re-solution and
re-crystallisation.——Another method is simply to evaporate the original
solution to dryness, by a steam heat, with agitation, then to re-dissolve
the residuum in the least possible quantity of boiling water, and, after
defecation or filtration, to allow the new solution to cool very slowly,
that crystals may form.
2. (Extemporaneous.) Add nitric acid, very gradually, to a cold solution
of ferrocyanide of potassium, with constant agitation, until a drop of the
mixture ceases to impart a blue colour to a solution of ferric chloride,
carefully avoiding excess of acid. It may be at once used in solution, or
evaporated, &c., as before.
_Prop, &c._ Magnificent regular prismatic or, sometimes, tubular crystals,
of a rich ruby-red tint; permanent in the air; combustible; decomposed by
a high temperature; soluble in 4 parts of cold water; insoluble in
alcohol. Colours ferric salts a pale brown, gives with ferrous salts a
deep blue, and precipitates bismuth salts pale yellow; cadmium and
mercuric salts, yellow; zinc salts, deep yellow; mercurous, cupric,
molybdenic, silver, and uranic salts, reddish brown; cobalt salts, dark
brown; manganous salts, brown; cupric salts, greenish; and nickelous
salts, olive brown.
=Potassium, Ethylate.= (C_{2}H_{5}KO.) Löweg and Weidmann obtained this
compound by heating together acetate of ethyl and potassium. Dr B. W.
Richardson, some few years ago, recommended the employment of the alkaline
ethylates as caustics, and they are now frequently used as such in
surgery. When first applied to the body the ethylates produce no action,
but as they absorb water from the tissues they are decomposed, the
potassium or sodium is oxidised, yielding caustic potash or soda in the
fresh condition, while alcohol is reformed from the recombination of
hydrogen derived from the water. Dr Richardson believes the ethylates of
potassium and sodium will be found the most effective and manageable of
all caustics, and that in cases of cancer, when it is important to destroy
structure without resorting to the knife, and in the removal of nævus and
other simple growths, they will be of essential service. The ethylates
dissolve in alcohol of different strengths; the solution may either be
applied with a glass brush or injected by the needle, and a slow or quick
effect can be insured according to the wish of the operator. The ethylate
of potassium is the more powerful agent.
=Potassium, Ferrocyanide of.= K_{4},FeCy_{6}, or K_{4},FeC_{6}N_{6}.
_Syn._ FERROCYANURET OF POTASSIUM, PRUSSIATE OF POTASH, YELLOW P. OF P.;
POTASSÆ PRUSSIA FLAVA (B. P.), POTASSII FERROCYANIDUM (Ph. L., E., & D.),
L. This valuable salt, the well-known ‘prussiate of potash’ of commerce,
was discovered by the illustrious Scheele about the middle of the 18th
century. It is now only manufactured on the large scale.
_Prep._ Good ‘potash’ or ‘pearlash,’ 2 parts, and dried blood, horns,
hoofs, woollen rags, or other refuse animal matter, 5 or 6 parts, are
reduced to coarse powder, and mixed with some coarse iron borings; the
mixture is then injected into egg-shaped cast-iron pots in a state of
moderate ignition; the mass is frequently stirred with an iron spatula, so
as to prevent it running together, and the calcination is continued until
fetid vapours cease to be evolved, and flame is no longer seen on stirring
the mixture, care being taken to exclude the air from the vessels as much
as possible; during the latter part of the process the pots are kept
constantly covered, and the ignited mass stirred less frequently; the hot
pasty mass is then removed with an iron ladle, and excluded from the air
until cold; it is next exhausted by edulcoration with boiling water, and
the resulting solution, after defecation or filtration, is concentrated by
evaporation, so that crystals may form as the liquid cools; these are
redissolved in hot water, and the solution allowed to cool very slowly,
when large and beautiful yellow crystals of ferrocyanide of potassium are
deposited.——_Product._ 1 ton of dried blood or woollen refuse, with 3 cwt.
of pearlash, yields from 2 to 2-1/2 cwt. of commercial ferrocyanide. The
mother-liquor contains sulphate of potassium.
_Prop._ It forms large and very beautiful yellow crystals, which are
permanent in the air, and very tough and difficult to powder; it is
soluble in 4 parts of cold and 2 parts of boiling water; has a mild saline
taste; at a gentle heat loses water; at a higher temperature, in closed
vessels, it is for the most part converted into cyanide of potassium, and,
when exposed to the air, into cyanate of potassium. Precipitates solutions
of antimonous, bismuth, mercurous, and zinc salts, white; cadmium salts,
of a pale yellow; cuprous salts, white, turning red; ferrous salts, white,
turning blue; lead salts, white; manganous salts, white, turned red;
mercuric salts, white, turning bluish; nickelous salts, white, turning
green; silver salts, white; stannous salts, white; cobalt salts, green;
cupric salts, chocolate red; ferric salts, dark blue; palladous salts,
green; stannic salts, yellow; uranic salts, reddish brown; and zinc salts,
white.
_Uses, &c._ Ferrocyanide of potassium is chiefly used in dyeing and calico
printing, in the manufacture of Prussian blue, in electro-plating, and, in
chemistry, as a test, and a source of hydrocyanic acid. As a medicine it
is said to be sedative and astringent, and in large doses purgative, but
appears to possess little action.——_Dose_, 10 gr. to 1/2 dr., dissolved in
water; in hooping-cough, chronic bronchitis, night-sweats, leucorrhœa, &c.
D’Arcet swallowed a solution containing 1/2 oz. of this salt without
experiencing any injurious effects.
=Potassium, Hydrate of.= KHO. _Syn._ POTASSA HYDRATE, HYDRATE OF POTASSA,
POTASSA, CAUSTIC P., HYDRATED OXIDE OF POTASSIUM; POTASSA CAUSTICA (B.
P.), POTASSA (Ph. E.), P. CAUSTICA (Ph. D.), P. HYDRAS (Ph. L.), P. FUSA.
_Prep._ 1. (Ph. L.) Liquor of potassa, 1 gall.; evaporate the water in a
clean iron vessel over the fire until the ebullition being finished, the
residuum of potassium hydrate liquefies; pour this into proper moulds.
2. (Ph. E. & D.) As the last, but pouring the fused hydrate upon a bright
and clean iron plate (silver or iron dish——Ph. D.); as soon as it
solidifies, break it quickly (into fragments), and put it into stoppered
glass (green-glass——Ph. D.) bottles.
3. (Pure.) The hydrate, obtained as above, is dissolved in alcohol or
rectified spirit, and, after repose for a few days in a closely stopped
green-glass or silver vessel, the solution is decanted, and cautiously
evaporated in a deep silver basin, out of contact with the air.
4. (Pure.) M. Polacci states that he procures very pure hydrate of potash
in a few minutes by the following process. He heats together in an iron
vessel to a red heat a mixture consisting of 1 part of nitrate of potash
well triturated with 2 or 3 parts of iron filings. The mass becomes red in
a few minutes, and, after cooling, it is treated with water, left to
settle, and then decanted. A more or less concentrated solution may thus
be obtained, or it may be evaporated to produce the solid potash.
_Prop., &c._ When perfectly pure it is white, solid, very soluble in water
and in alcohol; very deliquescent; intensely acrid and corrosive; and
exhibiting the usual signs of alkalinity in the highest degree. That of
the shops has usually a greyish or bluish colour.
=Potassium, I′odate of.= KIO_{3}. _Syn._ POTASSÆ IODAS. L. _Prep._
Neutralise a hot solution of hydrate of potassium with iodine, evaporate
to dryness by a gentle heat, powder the residuum, and digest it in
alcohol, to remove iodide of potassium, dissolve the insoluble portion in
hot water, and crystallise.
_Obs._ Iodate of potassium is resolved at a red heat into oxygen gas and
iodide of potassium. It has been recommended in bronchocele.——_Dose_, 1 to
5 gr.
=Potassium, Iodide of.= KI. _Syn._ POTASSII IODIDUM (B. P., Ph. L., E.,
and D.).
1. (Ph. L. 1836.) Take of iron filings, 2 oz.; distilled water, 2 quarts;
iodine, 6 oz,; mix them, and heat the solution until it turns green, and
then add of carbonate of potassium, 4 oz., dissolved in water, 1 quart;
filter, wash the residuum on the filter with water, evaporate the mixed
filtered liquors and crystallise.——_Product_, 1 oz. of iodine yields 1 oz.
45 gr. of iodide.
The formulæ of the Ph. D. and Ph. E. are very similar.
2. Add iodine to a hot solution of pure hydrate of potassium until the
alkali is perfectly neutralised, carefully avoiding excess; evaporate the
liquid to dryness, and expose the dry mass to a gentle red heat in a
platinum or iron crucible; afterwards dissolve out the salt, gently
evaporate, and crystallise. An excellent process, yielding a large
product, but, if the ignition be not carefully managed, it is apt to
contain a little undecomposed iodate. To obviate this, Mr Scanlan proposes
the addition of a little powdered charcoal to the mass before ignition——a
plan adopted in the Ph. U. S.
3. Iodine is treated with a small proportion of phosphorus in water, and
is thus converted into ‘hydriodic acid,’ hydrate of calcium is then added,
and the ‘iodide of calcium’ formed is first fused, and then decomposed by
sulphate of potassium into ‘sulphate of calcium,’ which is precipitated,
and ‘iodide of potassium,’ which remains in solution, and may be
crystallised, as in the other processes. This is a modification of a
method devised by Liebig.
4. (Ph. B.) Put solution of potash, 1 gall., into a glass or porcelain
vessel, and add iodine 29 oz., or q. s., in small quantities at a time,
with constant agitation, until the solution acquires a permanent brown
tint. Evaporate the whole to dryness in a porcelain dish, pulverise the
residue, and mix this intimately with wood charcoal in fine powder, 3 oz.
Throw the mixture, in small quantities at a time, into a red-hot crucible,
and when the whole has been brought to a state of fusion, remove the
crucible from the fire and pour out its contents. When the fused mass has
cooled, dissolve it in 2 pints of boiling distilled water, filter through
paper, washing the filter with a little distilled boiling water; unite the
liquids, and evaporate till a film forms on the surface. Set aside to cool
and crystallise. Drain crystals and dry quickly with a gentle heat; more
crystals may be obtained by evaporating the mother liquor, and cooling.
The salt should be kept in a stoppered bottle.
_Prop._ It crystallises in cubes, which in the pure salt are extremely
white, though frequently opaque; these are anhydrous; fuse when heated,
without decomposition; dissolve in less than an equal weight of water, at
60° Fahr., and very freely in alcohol; and do not deliquesce in moderately
dry air unless they contain undecomposed hydrate of potassium. Its
solution dissolves the iodine freely, and also, less readily, several of
the insoluble metallic iodides and oxides.
_Pur._ It is entirely soluble in both water and alcohol. Its aqueous
solution alters the colour of turmeric either not at all or but very
slightly, nor does it affect litmus paper, or effervesce with acids.
Nitric acid and starch being added together, it becomes blue. It is not
coloured by the addition of tartaric acid with starch. No precipitate
occurs on adding either a solution of hydrate of calcium or of chloride of
barium. 100 gr., dissolved in water, by the addition of nitrate of silver,
yield a precipitate of 141 gr. of iodide of silver.
_Assay._ The iodide of commerce frequently contains fully one half its
weight of either chloride or carbonate of potassium, or both of them, with
variable quantities of iodate of potassium, a much less valuable salt. The
presence of these substances is readily detected by the above tests. As
the first of these is only very slightly soluble in cold alcohol, and the
others insoluble in that liquid, a ready method of determining the
richness of a sample in pure iodide, sufficiently accurate for ordinary
purposes, is as follows:——Reduce 50 gr. of the sample to fine powder,
introduce this into a test tube with 6 fl. dr. of alcohol, agitate the
mixture violently for one minute, and throw the whole on a weighed filter
set in a covered funnel, observing to wash what remains on the filter with
another fl. dr. of alcohol. The filtrate, evaporated to dryness, gives
the quantity of pure iodide, and the filter, dried by the heat of boiling
water, that of the impurities present in the sample examined, provided it
contained no hydrate of potassium. The quantity of alkali, whether hydrate
or carbonate, may be found by the common method of ‘alkalimetry.’
_Uses, &c._ Chiefly in photography, medicine, and pharmacy.——_Dose_, 1 to
10 gr., twice or thrice daily, made into pills, or, better, in solution,
either alone or combined with iodine; in bronchocele, scrofula, chronic
rheumatism, dropsy, syphilis, glandular indurations, and various other
glandular diseases. Also externally, made into a lotion or ointment.
=Potassium, Nitrate of.= KNO_{3}. _Syn._ NITRATE OF POTASH, NITRE,
SALTPETER; POTASSÆ NITRAS (B. P., Ph. L., E.,& D.), NITRUM†, SAL NITRI†,
SAL PETRƆ, KALI NITRATUM†, L. This salt is produced naturally in the soil
by the action of the atmosphere, and crystallises upon its surface, in
various parts of the world, especially in the East Indies. On the
Continent it has long been produced artificially, by exposing a mixture of
calcareous soil and animal matter to the atmosphere, when calcium nitrate
is slowly formed, and is extracted by lixiviation. The liquid is then
decomposed by the addition of wood ashes, or carbonate of potassium, by
which carbonate of calcium is precipitated, and nitrate of potassium
remains in solution. The places where these operations are performed are
called ‘nitriaries,’ or ‘nitrières artificielles.’ The British market is
wholly supplied from India. The salt of the first crystallisation, by
either process, is called ‘crude nitre’ or ‘rough saltpetre.’ This is
purified by solution in boiling water, skimming, and, after a short time
allowed for defecation, straining (while still hot) into wooden
crystallising vessels. The crystals thus obtained are called ‘single
refined nitre,’ and when the process is repeated ‘double refined nitre.’
1. (POTASSÆ NITRAS PURUM——Ph. D.) Commercial nitre, 4 lbs.; boiling
distilled water, 1 quart; dissolve, withdraw the heat, and stir the
solution constantly as it cools; the minute crystals, thus obtained, are
to be drained, and washed, in a glass or earthenware percolator, with cold
distilled water, until that which trickles through ceases to give a
precipitate with a solution of nitrate of silver, the contents of the
percolator are then to be withdrawn, and dried in an oven.
_Prop._ White, pellucid, six-sided prisms; permanent in the air; soluble
in 7 parts of water at 60° and in 1 part at 212° Fahr.; insoluble in
alcohol; its taste is cool, saline, and slightly bitter and pungent; at
about 560° it fuses to an oily-looking mass, which concretes on cooling,
forming ‘sal prunella,’ at a red heat it gives out oxygen, and,
afterwards, nitrous fumes; sp. gr. 1·925 to 1·975.
_Pur._ Commercial nitre generally contains chlorides, sulphates, or
calcareous salts. The first may be detected by its solution giving a
cloudy white precipitate with nitrate of silver. The second by chlorides
of barium or calcium giving a white precipitate, and the third by oxalate
of ammonium giving a white precipitate.
_Assay._ Of the numerous methods prescribed for this purpose, few are
sufficiently simple for mere practical men. The proportion of chlorides,
sulphates, and calcareous salts may be determined as above; and the
general richness of the sample by the method of Gay-Lussac, modified as
follows:——100 gr. of the sample (fairly chosen) are triturated with 50 gr.
of lampblack and 400 gr. of common salt, and the mixture placed in an iron
ladle, and ignited or fused therein, due care being taken to prevent loss;
the residuum is exhausted with hot water, and the solution thus obtained
tested by the usual methods of alkalimetry for carbonate of potassium. The
quantity of carbonate found, multiplied by 2·125 or 2-1/8, gives the
per-centage richness of the sample in nitrate.
_Uses, &c._ Nitre is chiefly employed in the manufacture of gunpowder,
fireworks, and nitric acid. It is also used in medicine as a sedative,
refrigerant, and diaphoretic, and as a cooling diuretic. It has been
recommended in active hæmorrhages (especially spitting of blood), in
various febrile affections, in scurvy, and in herpetic eruptions; and it
has been highly extolled by Dr Basham as a remedy in acute
rheumatism.——_Dose_, 5 to 15 gr., every 2 hours. A small piece, dissolved
slowly in the mouth, frequently stops a sore throat at the commencement.
In large doses it is poisonous. The best treatment is a powerful emetic,
followed by opiates.
=Potassium, Nitrite of.= KNO_{2}. _Syn._ NITRITE OF POTASSA; POTASSÆ
NITRIS, L. _Prep._ 1. By heating nitre to redness, dissolving the fused
mass in a little water, and adding twice the volume of the solution in
alcohol; after a few hours the upper stratum of liquid is decanted, and
the lower one, separated from the crystals, evaporated to dryness.
2. (Corenwinder.) Nitric acid, 10 parts, are poured on starch, 1 part, and
the evolved gas passed through a solution of hydrate of potassium of the
sp. gr. 1·380, to saturation; the liquid is then either neutralised with a
little hydrate of potassium (if necessary), and kept in the liquid form,
or at once evaporated. Fused pinkish mass, or clear colourless soluble
crystals, used in chemistry as a reagent, and deoxidiser.
=Potassium, Oxalate of.= K_{2}C_{2}O_{4}. _Syn._ NEUTRAL OXALATE OF
POTASSA; POTASSÆ OXALAS, L. _Prep._ Neutralise a solution of oxalic acid,
or the acid oxalates, with carbonate of potassium, evaporate, and
crystallise. Transparent colourless rhombic prisms, soluble in 3 parts of
water, and of the formula K_{2}C_{2}O_{4},Aq.
=Potassium, Hydrogen Oxalate of.= KHC_{2}O_{4}. _Syn._ POTASSIUM
BINOXALATE, SALT OF SORREL, ESSENTIAL SALT OF LEMONS; POTASSÆ BINOXALAS,
L. _Prep._ By saturating a solution of oxalic acid, 1 part, with carbonate
of potassium, adding to the mixture a similar solution of 1 part of oxalic
acid, unneutralised, and evaporating for crystals. It may also be obtained
from the expressed juice of wood or sheep’s sorrel, by clarifying it with
eggs or milk, and evaporating, &c., as before. Colourless rhombic crystals
of the formula KHC_{2}O_{4},Aq., soluble in 40 parts of cold and 6 parts
of boiling water, yielding a very sour solution.
=Potassium, Trihydrogen Oxalate of.= KH_{3}(C_{2}O_{4}), or KHC_{2}O_{4},
H_{2}C_{2}O_{4}. _Syn._ POTASSIUM QUADROXALATE, POTASSIUM ACID OXALATE.
_Prep._ By neutralising 1 part of oxalic acid with carbonate of
potassium, adding to the solution 3 parts more of oxalic acid,
evaporating and crystallising. Resembles the last; has the formula
KH_{3}(C_{3}O_{4})_{2},2Aq; but is less soluble, and more intensely sour,
and forms modified octahedral crystals. The salt is occasionally sold
under the names of ‘sal acetosellæ,’ ‘salt of sorrel,’ and ‘essential salt
of lemons.’ Both are used to remove ink and iron stains from linen, to
bleach the straw used for making bonnets, and, occasionally, in medicine,
as a refrigerant.
=Potassium, Oxide of.= K_{2}O. _Prep._ Burn pure potassium in a current of
oxygen. White powder, rapidly absorbing water and forming the hydrate.
=Potassium, Perchlorate of.= KClO_{4}. _Syn._ POTASSÆ PERCHLORAS, L.
Prepared by projecting well-dried and finely powdered chlorate of
potassium in small portions at a time, into warm nitric acid. The salt is
separated from the ‘nitrate’ by crystallisation.
=Potassium, Prus′siate of.= See POTASSIUM FERRICYANIDE and FERROCYANIDE.
=Potassium, Salicylite of.= Formed by mixing salicylous acid (artificial
oil of meadow-sweet) with a strong solution of hydrate of potassium; it
separates, on agitation, as a yellow crystalline mass, which, after
pressure in bibulous paper, is recrystallised from alcohol. Golden-yellow
crystals, soluble in both water and alcohol; damp air gradually converts
them into acetate of potassium and melanic acid.
=Potassium, Silicate of.= (Ure.) _Syn._ POTASSÆ SILICAS. _Prep._ Mix 1
part of powdered quartz or flint, or of fine siliceous sand with 2 parts
of carbonate of potash, and fuse them in a Hessian crucible. Dissolve the
mass in water, filter the solution and evaporate it to dryness——_Dose_, 10
gr. to 15 gr. in 6 or 8 oz. of water, twice a day. To dissolve gout
concretions. An impure silicate of potash is used as a water-glass.
=Potassium, Sulphate of.= K_{2}SO_{4}. _Syn._ POTASSÆ SULPHAS (B. P., Ph.
L., E., & D.). _Prep._ The sulphate of potassium of commerce is a
secondary product of several chemical and manufacturing processes. Thus,
the residuum of the distillation of nitric acid from nitre is dissolved
in water, the solution neutralised with carbonate of potassium, and, after
defecation, evaporation until a pellicle forms; it is then strained, or
decanted, and set aside to crystallise. Or, the residuum is simply
ignited, to expel excess of acid, and then dissolved and crystallised as
before.
_Prop., &c._ Anhydrous, heavy, quartz-like crystals; permanent in the air;
soluble in 12 parts of water at 60° and in 5 parts at 212° Fahr.;
insoluble in alcohol; extremely nauseous, and bitter-tasted. It crepitates
on the application of heat; fuses at a red heat, but loses nothing in
weight. 100 gr. dissolved in distilled water, on the addition of chloride
of barium and hydrochloric acid, furnish 132 gr. of sulphate of barium,
dried at a red heat.
=Potassium, Bisulphate of.= KHSO_{4}. _Syn._ POTASSIUM-HYDROGEN SULPHATE,
ACID POTASSIUM SULPHATE; POTASSÆ BISULPHAS. _Prep._ 1. (Anhydrous.)
Neutral sulphate of potassium and oil of vitriol, equal parts; hot water,
q. s. (not more) to dissolve; anhydrous bisulphate crystallises out, in
long delicate needles, as the solution cools. If these are left for
several days in the mother-liquor they are redissolved, and crystals of
the ordinary hydrated bisulphate are deposited.
2. (Hydrated,)——_a._ (Ph. L. 1836.) Salt left in distilling nitric acid, 2
lbs.; boiling water, 3 quarts; dissolve; add of sulphuric acid 1 lb.;
concentrate by evaporation, and set the liquid aside, so that crystals may
form.
_b._ (Ph. D.) Sulphate of potassium (in powder), 3 oz.; sulphuric acid, 1
fl. oz.; mix them in a porcelain capsule, and expose it to a heat capable
of liquefying its contents, until acid vapours cease to be evolved; powder
the residuum, and preserve it in a well-stopped bottle.
_Prop., &c._ Sour and slightly bitter-tasted rhombic prisms; soluble in
about 2 parts of cold and 1 part of boiling water, the solution exhibiting
a strongly acid reaction. It is much employed, in lieu of tartaric acid,
for the production of carbonic acid, in ‘gazogenes,’ &c.; also to
adulterate cream of tartar and tartaric acid. According to Dr Paris, it
forms a “grateful adjunct to rhubarb.”——_Dose_, 12 gr. to 1-1/2 dr., in
solution, combined with rhubarb or bitters, as the neutral sulphate.
=Potassium, Sulphide of.= _Syn._ SULPHURET OF POTASSIUM, LIVER OF
SULPHUR†; POTASSII SULPHURETUM (Ph. L., E., & U. S.), HEPAR SULPHURIS (Ph.
D.), L. _Prep._ 1. (Ph. E.) Sulphur, 1 oz.; carbonate of potassium, 4 oz.;
mix, heat them in a covered crucible till they form a uniform fused mass;
when cold, break it into fragments, and preserve it in well-closed
vessels. The formulæ of the Ph. L. 1836 and Ph. U. S. are similar.
2. (Ph. D.) Sublimed sulphur, 4 oz.; carbonate of potassium (from
pearlash, first dried, and then reduced to powder), 7 oz.; mix in a warm
mortar, heat them in a Hessian crucible, as before, pour the fused mass
into an iron cup, over which immediately invert a second vessel, to
exclude the air, and, when cold, break the mass into fragments, and
preserve it in a green-glass stoppered bottle.
_Prop., &c._ A hard, brittle, liver or greenish-brown coloured solid;
inodorous whilst dry; soluble in water, forming a highly-fetid solution;
and, in acids, evolving strong fumes of sulphuretted hydrogen; reaction,
alkaline; exposed to the air, it is gradually converted into sulphate of
potassa. As a medicine it is reputed diaphoretic, expectorant, and
stimulant.——_Dose_, 2 to 6 gr., in solution, or made into pills with soap;
in gout, rheumatism, liver affections, and various chronic skin diseases.
Externally, made into a lotion and ointment. It is highly acrid and
corrosive, and in large doses poisonous.
=Potassium, Sulphocyanide of.= KCNS, or KCyS. _Syn._ SULPHO-CYANURET OF
POTASSIUM; POTASSII SULPHOCYANIDUM, P. SULPHO-CYANURETUM, L. _Prep._ 1.
Ferrocyanide of potassium (anhydrous, or dried by a gentle heat), 46
parts; sulphur, 32 parts; pure carbonate of potassium, 17 parts; reduce
them to powder, and very gradually heat the mixture to low redness in a
covered iron crucible, which it will less than one half fill; remove the
half-refrigerated and still soft mass, crush it, exhaust it with water,
and evaporate the aqueous solution to dryness; powder the residuum, and
exhaust it with hot alcohol or rectified spirit; the alcoholic solution
will yield beautiful white crystals as it cools, and the residuum or
mother-liquor may be evaporated for the remainder of the salt.
2. Cyanide of potassium, 3 parts; sulphur, 1 part; water, 6 parts; digest
them together for some time, add 3 parts more of water, filter, evaporate,
and crystallise.
_Prop., &c._ Long, slender, colourless prisms or plates, which are
anhydrous, bitter-tasted, deliquescent, fusible, very soluble in both
water and alcohol, and non-poisonous. It is chiefly used as a test for
ferric oxide, for which purpose it is preferable to all other substances.
=Potassium, Tartrate of.= K_{2}C_{4}H_{4}O_{6}. _Syn._ NEUTRAL TARTRATE OF
POTASSIUM, TARTRATE OF POTASSA, NEUTRAL TARTAR, SOLUBLE T.; POTASSÆ
TARTRAS (B. P., Ph. L., E., & D.), KALI TARTARIZATUM†, L. _Prep._ (Ph. D.)
Carbonate of potassium, 8 oz.; distilled water, 2 quarts; dissolve, and to
the solution, whilst boiling hot, gradually add of bitartrate of
potassium, in fine powder, 1 lb., or q. s., so that the liquid, after
ebullition for a couple of minutes, ceases to change the colour of either
blue or reddened litmus paper; next filter the liquid through calico,
evaporate it until a pellicle forms on the surface, and set it aside to
crystallise; after 12 hours collect the crystals, dry them on bibulous
paper, and preserve them from the air. The formula of the Ph. L. 1836 is
nearly similar.
_Prop., &c._ The crystals of this salt, which are obtained with
difficulty, are right rhombic prisms, and are deliquescent. The salt of
commerce is usually in the form of a white granular powder, which is
obtained by simply evaporating the solution to dryness, with constant
stirring. In this state it requires about 4 parts of cold water for
its solution. Acids convert it into the bitartrate. As a medicine it
acts as a gentle diuretic and aperient, and is valued for correcting
the griping properties of senna and resinous purgatives. It is also
antiscorbutic.——_Dose_, 1/2 dr. to 3/4 oz., in powder, or dissolved in
water. The solution changes the colour neither of litmus nor turmeric. The
addition of almost any acid throws down crystals of bitartrate of
potassium, which generally adhere to the vessel. The precipitate
occasioned by either chloride of barium or acetate of lead is dissolved by
dilute nitric acid.
=Potassium, Bitartrate of.= KHC_{4}H_{4}O_{6}. _Syn._ ACID TARTRATE OF
POTASSA, SUPER-TARTRATE OF P., CREAM OF TARTAR; CREMOR TARTARI, POTASSÆ
BITARTRAS (B. P., Ph. L., E., & D.), POTASSÆ SUPER-TARTRAS, TARTARI
CRYSTALLI, L. This well-known salt is deposited during the fermentation of
grape juice as a crust on the sides of the casks or vats. In its
unprepared or crude state it is called white or red tartar or argol,
according to the wine from which it has been obtained. It is purified by
boiling it in water, crystallisation, re-solution in water, and treatment
with freshly burnt charcoal and aluminous clay, to remove the colour; the
clear liquid is then decanted, whilst still hot, and allowed to cool
slowly; the resulting crystals form the ‘cream of tartar’ of commerce.
_Prop., &c._ Small, translucent, gritty, prismatic crystals, irregularly
grouped together; permanent in the air; requiring fully 100 parts of cold
water, and about 15 parts of boiling water, for their perfect solution;
the solution has a harsh, sour taste, and, like that of the tartrate,
suffers spontaneous decomposition by keeping. Its solution reddens litmus.
At a red heat it is converted into carbonate of potassium. Entirely
soluble in 40 parts of boiling water; 40 gr., in solution, are neutralised
by 30 gr. of crystallised carbonate of soda.——_Dose._ As an aperient, 1 to
3 dr.; as a diuretic, 1/2 dr. to 1 dr.; as an antiscorbutic, 10 to 20 gr.
frequently. It is much used to make a pleasant cooling drink (‘Imperial’),
and in tooth-powders.
=POTA′TO.= This well-known and valuable article of food is the tuber of
the _Solanum tuberosum_ or _esculentum_, a plant which was introduced to
this country by either Sir Francis Drake or Sir Walter Raleigh, towards
the latter part of the 16th century. It is now extensively cultivated in
all the temperate climates of the world. It yields a vast quantity of
food on a small space of ground, but only about 1-7th part of the weight
of the tuber is nutritious, and this is chiefly farinaceous. Its farina or
starch is, however, accompanied by no inconsiderable portion of saline
matter, more especially of potassa, which renders it highly antiscorbutic,
and a powerful corrective of the grossness of animal food. When forming
part of a mixed diet, perhaps no substance is more wholesome than the
potato, and, certainly, no other esculent hitherto discovered appears
equally adapted for universal use.
Boussingault gives the following as the average composition of the tubers
of the potato:——
Moist Dry.
Water 75·9 ——
Albumen 2·3 9·6
Oily matter 0·2 0·8
Fibre 0·4 1·7
Starch 20·2 83·8
Salts 1·0 4·1
—————— ——————
100·0 100·0
Manuring experiments on potatoes in 1867-1869 show that on light soils a
mixture of mineral superphosphate, crude potash salts, and ammonium
sulphate, produces very beneficial results; on stiff soils nitrogenous
manures have little effect. Further proof is given that manuring with
common salt tends to decrease the yield.
Analyses, conducted by A. Stockardt, of potatoes grown in eight different
years, show that those manured with salt invariably contain less starch
than those unmanured, the decrease being from 10 to 20 per cent. of
starch; the same effect is produced when the salt is mixed with other
manures.
Under the microscope the cells are seen to be very sparingly fitted with
starch grains.
Unmanured potatoes contained ·43 per cent. of sodium chloride in the dry
substance, and those which had received a small dressing of common salt
1·34 per cent.[121]
[Footnote 121: Voelcker ‘Roy. Agric. Society’s Journal,’ quoted in
‘Journal of Chemical Society,’ vol. XXV.]
No certain rule can be laid down for ‘dressing’ potatoes. “If boiled, it
may be that they require to be put into boiling water, or, may be, into
cold, and either boiled quickly or slowly; but this you must find out.
Choose them all about the same size, with a smooth skin, and when they are
boiled and begin to crack, throw off the water immediately, as it only
damages the root. When dressed let them stand near the fire, with a cloth
over them, and serve them in their skins. Salt may be put into the water
at the beginning. A watery potato will require quick boiling, and,
sometimes, to be put into boiling water.” (Soyer.)
To retain the highest amount of nourishment in potatoes they should be
‘dressed’ with their skins on them. The bruised or damaged parts,
worm-holes, &c., being removed with a knife, the dirt should be carefully
cleaned out of the ‘eyes,’ and from the rough parts of the skins, by means
of a brush and water, after which they should be well rinsed in clean
water, and drained in a colander. If they are at all dry or shrivelled,
they may be advantageously left to soak for 3 or 4 hours in clean cold
water before cooking them. Potatoes ‘dressed’ in the skins have been found
to be nearly twice as rich in potassa salts as those which have been first
peeled. The skins are easily removed before sending them to table.
NEW POTATOES should have their loose outer skin rubbed off with a cloth or
stiff brush before being dressed or cooked.
[Illustration: Potato starch granules.]
[Illustration: Potato starch granules swollen by liquor potassæ.]
MASHED POTATOES are prepared by crushing, with the back of a spoon, or
with a rolling-pin, the hot ‘dressed’ tubers, placed in a bowl or dish, or
on a pie-board. A little milk, butter, and salt may be added to them at
will, and they may be either at once ‘served up,’ or pressed into ‘forms,’
and first ‘browned off’ in the oven. Potatoes, if not soft and mealy, and
well masticated, frequently escape the solvent action of the stomach, and
pass off undigested, often to the serious derangement of the health. By
mashing them this inconvenience is removed. The delicate, the dyspeptic,
and the aged should take them in no other form.
Potatoes may be preserved so as to stand the longest voyages unchanged, by
thoroughly desiccating them in an oven, or by steam heat. For this purpose
the roots, either raw or three parts dressed, are generally first cut into
dice of above 3/4 inch square, to facilitate the operation. Under a patent
granted to Mr Downes Edwards, Aug., 1840, the boiled potatoes are mashed
and granulated by forcing them through a perforated plate before drying
them. The granulated product, beaten up with a little hot milk or hot
water, forms an excellent extemporaneous dish of mashed potatoes.
The microscopic detection of potato starch is easy. Instead of being round
or oval, and with a central hilum, the starch grains are pyriform, with an
eccentric hilum placed at the smaller end, and with well-marked concentric
rings. A weak solution of liquor potassæ (one drop of the Pharmacopœia
preparation to ten of water) swells them out greatly after a time; while
wheat starch is little affected by potash of this strength; if the
strength is 1 to 3 (as in the _figs._) the swelling takes place very
rapidly.
=POT POURRI.= [Fr.] A mixture of odorous flowers, roots, gums, &c., varied
according to the taste of the operator, either mixed together dry, or in
the fresh state preserved with salt. “The usual way of making it is to
collect roses, lavender, and other sweet-scented flowers, as they blow; to
put them into a large jar mixed (stratified) with salt, until a sufficient
quantity has been collected; then to add to these such other odorous
substances as may be required to form an agreeable perfume.” Among the
substances thus added are——ambergris, benzoin, calamus root, cascarilla,
cassia, cassia buds, cinnamon, civet, cloves, musk, musk seed, orange
berries and flowers, orris root, pimento, storax, vanilla, yellow sandal
wood, &c.
“Instead of the fresh flowers, dried roses are sometimes used, and, with
the addition of some essential oils, these answer quite as well.”
(Redwood.)
The following is a French formula:——Take the petals of the pale and red
roses, pinks, violets, moss rose, orange flower, lily of the valley,
acacia flowers, clove gilliflowers, mignonette, heliotrope, jonquils, with
a small proportion of the flowers of myrtle, balm, rosemary, and thyme;
spread them out for some days, and as they become dry put them into a
jar, with alternate layers of dry salt mixed with orris powder, till the
vessel is filled. Close it for a month and stir the whole up, and moisten
it with rose water.
=POT′TED MEATS.= See PUTREFACTION and POTTING (_below_).
=POT′TERY.= The mechanical operations connected with the manufacture of
pottery (CERAMIC ART) do not come within the province of this work. The
materials employed, in this country, to produce the best kind of
earthenware (STAFFORDSHIRE WARE) are the fine white clays of Devonshire
and Cornwall, and powdered chert or flint. This is brought to a perfectly
homogeneous plastic mass with water, and in this state is fashioned upon
the potter’s wheel and lathe, or by moulding, into all the varied objects
of utility and ornament, which are made in this material. After the newly
formed vessels and other articles have been dried by exposure in heated
rooms, they are enclosed in clay cases (SEGGARS) and exposed to heat in a
kiln, by which they arrive at a state (BISCUIT) which renders them fit for
glazing; the patterns (if any) and, afterwards, appropriate vitreous
materials having been applied to their surfaces, they are again placed in
the seggars, and are again exposed in a kiln to a heat sufficiently high
to fuse the newly applied compound, by which they acquire a uniform
enamelled surface, and become fit for the market. PORCELAIN, or CHINA, as
it is commonly called, is manufactured in a nearly similar manner, but the
materials are selected and the various processes conducted with
corresponding skill and care.
The ornamental patterns are produced upon both Staffordshire ware and
porcelain by a number of ingenious processes, among which printing,
painting, and moulding are the principal. The colours employed are those
which have been already referred to under ENAMELS.
The metallic lustres now so common on stoneware, &c., are given as
follows:——
1. GOLD LUSTRE. Dissolve grain-gold, 1 dr., in aqua regia, 3/4 oz.; to the
solution add of metallic tin, 6 gr.; and when this is dissolved, pour it
very gradually, with constant stirring, into a mixture of balsam of
sulphur, 1/2 dr.; oil of turpentine, 20 gr.; when the mass begins to
stiffen, 1/2 dr. more of oil of turpentine must be added, and well mixed
in. More gold deepens and brightens the lustre; more tin turns it on the
violet or purple.
2. IRON LUSTRE. From a mixture of ‘muriate of iron’ (ferric chloride) and
spirit of tar.
3. PLATINUM LUSTRE. To a solution of platinum in aqua regia (platinic
chloride) is added, drop by drop, a mixture of spirit of tar and balsam of
sulphur in equal proportions, until by a trial the composition is found to
give the required result. This gives the appearance of polished steel.
4. SILVER LUSTRE. The ammonio-chloride of platinum is reduced to an
impalpable powder, ground up to the requisite consistence with a little
spirit of tar, and at once applied with a brush.
The above lustres are applied, over an easily fusible glaze, to the outer
surfaces only of the vessels, after which adhesion is produced by exposing
the pieces to a slight degree of heat in the muffle. To give them their
full beauty they must be rubbed with cotton, wool, or chamois leather,
after the firing. See ALUMINA, CLAY, ENAMELS, GILDING, GLAZES, KAOLIN, &c.
=POT′TING.= A term commonly applied to the operation or practice of
preserving animal substances in a state fit for immediate use, in small
pots or jars. The method of proceeding is, first, to mince the substance
(previously well dressed, and carefully deprived of bones, sinews, skin,
&c.), and, next, to pound it in a clean polished marble or iron mortar,
along with a little butter and some cayenne pepper, or other suitable
spice or sauce, until it forms a perfectly smooth paste; this is pressed
into the pots, so as to about 2-3rds fill them, and clarified melted
butter is then poured in to the depth of about 1-8th of an inch; the pots
are, lastly, closely covered over, and kept in a cool situation. In this
state their contents may be preserved for a year, or longer. Potted beef,
ham, veal, poultry, game, anchovies, bloaters, salmon, &c., are commonly
sold in the shops. They are all intended for relishes, and are spread upon
bread in the same manner as butter.
=POUDRE KOUSIQUE.= [Fr.] A French nostrum, consisting of nitre and
sulphur, of each 50 parts; charcoal and antimony, of each 1 part. It is
divided into 1/2-dr. doses, of which three are put into each packet. It is
given to dogs in a ball of butter, to prevent the disorders to which they
are liable.
=POUDRE METALLIQUE.= [Fr.] See TOOTH CEMENTS.
=POUDRE SUBTILE.= [Fr.] See DEPILATORY.
=POUDRETTE.= [Fr.] Dried night-soil. The manure sold under this name is a
compound of night-soil with clay, charcoal, or gypsum, made into balls or
cakes. Its extensive use in Belgium, France, the United States of America,
and, more particularly, in China, where it was first employed, has shown
it to be the most fertilising and generally applicable of all the numerous
substances used as manure. Unfortunately, the prejudices of Englishmen
lead them to poison the air of their cities and towns, and the waters of
their rivers, with a substance which, if rightly applied, would crown
their fields with golden harvests, and drive pauperism from the land.
Tardieu, speaking of the men engaged in making poudrette, says:——“The
action of the exhalations from the manure manufacturers is certainly not
injurious. The workmen show actually no trace of sickness or disease
which can be referred to the influence of these exhalations.”
That ‘poudrette’ is, however, occasionally liable to set up fermentation
seems undeniable; and when this is the case, and large quantities of
poudrette are stored within a small space, serious consequences may ensue.
Parent Duchâtelet cites the case of a vessel carrying poudrette to
Guadaloupe, in which half the crew died, and the remainder were in a very
low state of health on the arrival of the vessel at Guadaloupe, owing, as
he affirms, to the exhalations given off by the poudrette.
=POUL′TICE.= _Syn._ CATAPLASM; CATAPLASMA, L. An external application,
generally extemporaneous, used to promote suppuration, allay pain and
inflammation, resolve tumours, &c.
Poultices (cataplasmata) are generally prepared with substances capable of
absorbing much water, and assuming a pulpy consistence, so as to admit of
their application to any surface, however irregular. Their curative action
principally depends upon the liquids with which they are moistened, and
the heat retained by the mass. With this object they should never be heavy
or very bulky, and should be frequently repeated, and lightly, but
securely, bandaged on, to prevent displacement.
The addition of a little lard, olive oil, or, still better, glycerin, to a
poultice, tends greatly to promote its emollient action, and to retard its
hardening.
As the continued medication of the part with warmth and moisture, or with
substances applied in the moist way, is the principal object to be
attained in the application of poultices, a fold or two of lint or soft
linen dipped in hot water, either simple or medicated, and covered with a
piece of thin sheet gutta percha or india-rubber cloth, to prevent
evaporation, may be often conveniently applied in their stead. A very
elegant and useful substitute of this kind is sold under the name of
‘spongio piline.’ Its cleanliness, lightness, and ease of application has
led to its extensive adoption by the medical profession.
The following formulæ embrace all the cataplasma of the Pharmacopœias:——
=Poultice of Al′um.= _Syn._ CATAPLASMA ALUMINIS, L. _Prep._ (B. P., Ph. D.
1826.) Alum (in powder), 1 dr.; whites of 2 eggs; shake them together
until they form a coagulum. Applied, between the folds of fine linen, to
chilblains, sore nipples, inflamed eyes, &c.
=Poultice, Anodyne.= (P. Cod.) _Syn._ CATAPLASMA ANODYNUM. _Prep._ Poppy
heads, 1 oz.; dried leaves of henbane, 2 oz.; water, 24 oz. Boil, strain,
and add to the liquor 4 oz. of emollient meals, to form a poultice.
=Poultice, Antiseptic.= (Fr. Hosp.) _Syn._ CATAPLASMA ANTISEPTICUM.
_Prep._ Barley flour, 6 oz.; powdered Peruvian bark, 1 oz.; water, q. s.
Boil and, when cool enough, add camphor in powder, 1 dr.
=Poultice, Astringent.= (Foy.) _Syn._ CATAPLASMA ASTRINGENS. _Prep._
Catechu, 1 oz.; powdered oak bark and barley meal, of each 1 oz.; cold
water, q. s.
=Poultice of Belladonna.= (Dr Reece.) _Syn._ CATAPLASMA BELLADONNÆ.
_Prep._ Extract of belladonna, made in vacuo, 1 dr.; oatmeal, 1/2 lb.;
boiling water, q. s.
=Poultice, Bran.= _Syn_. CATAPLASMA FURFURIS. _Prep._ Fine bran, with one
tenth of linseed meal, made into a poultice with boiling water. Mr Payne
recommends, as a cheap hospital poultice, 3-1/2 pecks of pollard, 14 lbs.
of bruised meal, and 1/4 lb. of lard.
=Poultice of Bread.= _Syn._ CATAPLASMA PANIS, L. _Prep._ From crum of
bread, soaked in hot water, slightly pressed, and then beaten up with a
little lard, butter, or oil. Emollient. See POULTICE, LINSEED MEAL
(_below_).
=Poultice of Car′rot.= _Syn._ CATAPLASMA DAUCI, L. _Prep._ 1. From the
common esculent carrot, scraped fine, so as to form a pulp.
2. (Ph. D. 1826.) From the cultivated carrot boiled with a little water
until it becomes soft enough to form a poultice. Anodyne and antiseptic.
Used in foul and painful ulcers, burns, contusions, &c. That from the
first formula is the more stimulant.
=Poultice of Char′coal.= _Syn_. CATAPLASMA CARBONIS (B. P., Ph. L.), C. C.
LIGNI, L. _Prep._ 1. (Ph. L.) Soak bread, 2 oz., in boiling water, 1/2
pint; to this add, by degrees, of linseed meal, 10 dr.; and, afterwards,
of powdered (recently burnt) charcoal, 2 dr.; lastly, sprinkle on the
surface of the poultice powdered charcoal, 1 dr. As an application to
fetid and gangrenous sores; frequently renewed.
2. (B. P.) Wood charcoal, 1/2 oz.; bread, 2 oz.; linseed meal, 1-1/2 oz.;
boiling water, 10 oz.; soak the bread in the water near the fire, add the
linseed meal and half the charcoal, stirring to a soft poultice,
sprinkling the remainder of the charcoal on the surface.
=Poultice of Chlo′′ride of So′da.= _Syn._ CATAPLASMA SODÆ CHLORINATÆ (B.
P., Ph. L.), L. _Prep._ 1. (Ph. L.) Boiling water, 6 fl. oz.; linseed
meal, 4-1/2 oz.; mix gradually, then add of solution of chlorinated soda,
2 fl. oz. Applied to foul ulcers, gangrenous parts, &c.
2. (B. P.) Solution of chlorinated soda, 1; linseed meal, 2; boiling
water, 4; add the linseed meal gradually to the water, stirring
constantly, then mix the solution of chlorinated soda.
=Poultice, Compound Farina.= _Syn._ CATAPLASMA FARINÆ COMPOSITUM. _Prep._
Rye flour, 1 lb.; old yeast, 4 oz.; salt, 2 oz.; hot water, q. s.
=Poultice, Cummin.= (L. Ph. 1788.) _Syn_. CATAPLASMA CUMINI. _Prep._
Cummin seeds, 1 lb.; bay berries, scordium leaves, serpentaria root, of
each 3 oz.; cloves, 1 oz.; to be powdered together and mixed with thrice
their weight of honey.
=Poultice, Discutient.= _Syn._ CATAPLASMA DISCUTIENS. _Prep._ Barley meal,
6 oz.; fresh hemlock, 2 oz.; vinegar, q. s. Boil and add sal ammoniac, 1/2
oz. (Fr. Hosp.) The same, with 2 dr. of acetate of lead added.
=Poultice, Effervescing.= _Syn._ CATAPLASMA EFFERVESCENS. _Prep._ Fresh
wort thickened with oatmeal, and a spoonful of yeast added.
=Poultice, Emetic.= _Syn._ CATAPLASMA EMETICUM. _Prep._ Bruised groundsel
(_Senecio vulgaris_) applied over the stomach produces vomiting.
=Cataplasma of Fig.= _Syn._ CATAPLASMA FICI. _Prep._ A dried fig, roasted
or boiled (sometimes in milk), is frequently applied to gum-boils, &c.
=Poultice, Foxglove.= (Mr Alland.) _Syn._ CATAPLASMA DIGITALIS. _Prep._ A
strong decoction of foxglove, with bread-crum, or linseed meal, q. s.
=Poultice, Galbanum.= _Syn._ CATAPLASMA GALBANI. _Prep._ Lily roots, 4
oz.; figs, 1 oz.; boil till soft, and bruise them with 1-1/2 oz. of onions
and 1/2 oz. of galbanum, triturated with yolk of egg and a sufficient
quantity of linseed meal.
=Poultice, Galvanic.= (Recamier.) _Syn._ CATAPLASMA GALVANICUM. It
consists of cotton wadding containing a layer of very thin zinc plates,
and another layer of copper ones. This pad, conveniently quilted, is
enclosed in a bag, one face of which is of quilted calico, the other of
impermeable tissue. The natural perspiration, confined by the impermeable
tissue, excites galvanic action between the metals.
=Poultice of Hem′lock.= _Syn._ CATAPLASMA CONII (B. P., Ph. L.), L.
_Prep._ 1. (Ph. L.) Boiling water, 1/2 pint; linseed meal, 4-1/2 oz., or
q. s.; make a poultice, and on this spread of extract of hemlock (Ph. L.),
1 oz., first softened with a little hot water. Anodyne. In irritable and
painful cancerous, scrofulous, and syphilitic sores, tumours, &c.
2. (B. P.) Hemlock leaf, in powder, 1 oz.; linseed meal, 3 oz.; boiling
water, 10 oz.; mix the ingredients, then add them to the water gradually,
constantly stirring.
=Poultice, Henbane.= _Syn._ CATAPLASMA HYOSCYAMI. The same as POULTICE OF
POPPY.
=Poultice, Hop.= (Dr Trotter.) _Syn._ CATAPLASMA HUMULI. Hops softened
with hot water. To foul ulcers.
=Poultice, Iodine.= _Syn._ CATAPLASMA IODURETUM. To a common poultice add
solution or tincture of iodine.
=Poultice, Lead.= _Syn._ CATAPLASMA PLUMBI. _Prep._ Goulard water, 1 lb.;
bread crum, q. s.
=Poultice, Lily.= _Syn._ CATAPLASMA LILII. The pulp of the white lily
boiled and bruised.
=Poultice, Lime.= _Syn._ CATAPLASMA CALCIS. _Prep._ Slaked lime, 2 oz.;
oatmeal, 2 oz.; lard, 4 oz. Formerly used at Bath Hospital.
=Poultice of linseed Meal.= _Syn._ CATAPLASMA LINI (B. P., Ph. L.), L.
_Prep._ 1. (Ph. L.) To boiling water, 1/2 pint, add, gradually,
constantly stirring, of linseed meal, 4-1/2 oz., or q. s. Emollient. Used
to promote the suppuration or ‘ripening’ of tumours. A little oil or lard
should be added, and some smeared over the surface as well, to prevent its
getting hard. For small ‘gatherings,’ as of the fingers, a little chewed
bread and butter is an efficient and convenient substitute.
2. (B. P.) Linseed meal, 4; olive oil, 1/2; boiling water, 10; mix the
linseed meal with the oil, add the water gradually, constantly stirring.
_Obs._ Linseed meal prepared from the cake, from which the oil has been
expressed, is less adapted for poultices than that prepared from the
unpressed, whole seed. The latter is ordered in the Ph. L.
=Poultice, Malt.= (Guy’s Hosp.) _Syn._ CATAPLASMA BYNES. _Prep._ Ground
malt, with yeast, q. s., to form a poultice; to be applied warm.
=Poultice, Maturative.= (L. 1745.) _Syn._ CATAPLASMA MATURANS. _Prep._
Pulp of figs, 4 oz.; resin ointment, 1 oz.; strained galbanum, 1/2 oz.
=Poultice of Mus′tard.= _Syn._ CATAPLASMA SINAPIS (Ph. L.), L. _Prep._ 1.
(B. P., Ph. L.) Linseed meal and powdered mustard, of each 2-1/2 oz., or
q. s.; boiling water, 1/2 pint; mix as before.
2. (Ph. L. 1836.) As the last, but substituting boiling vinegar for water.
Used as a powerful counter-irritant, stimulant, and rubefacient; in low
fevers, apoplexy, coma, &c., where there is a determination of blood to
the head; in deep-seated inflammatory pains, neuralgic pains, &c. It
should not be left on long enough to raise a blister. See PLASTERS.
=Poultice, Onion.= _Syn._ CATAPLASMA CEPÆ. _Prep._ Onions roasted and
mashed.
=Poultice of Pop′py.= _Syn._ CATAPLASMA PAPAVERIS, L. _Prep._ 1. (P. Cod.
1839.) A strong decoction of poppies, thickened with crum of bread.
Anodyne.
=Poultice, Potash, Acetate of.= _Syn._ CATAPLASMA POTASSÆ ACETATIS;
CATAPLASMA NEUTRALE. _Prep._ Acetate of potash, 1 oz.; water, 1 pint; crum
of bread, q. s. To ill-conditioned sores.
=Poultice of Po′tato.= _Syn._ CATAPLASMA SOLANI TUBEROSI, L. _Prep._ From
the raw potato, scraped or grated fine. A popular application to fresh
bruises, extravasations, burns, scalds, &c.
=Poultice of Potato Starch.= (P. Cod.) _Syn._ CATAPLASMA FECULÆ. _Prep._
Potato starch, 2 oz.; mix with a little cold water, add to it 20 oz. of
boiling water, and boil for an instant. Cataplasms of rice and wheat
starch are made in the same manner.
=Poultice, Pradier’s.= _Syn._ PRADIER’S CATAPLASMA; CATAPLASME DE PRADIER,
Fr. _Prep._ Take of balsam of Mecca, 6 dr.; rectified spirit, 16 oz.;
dissolve; next, separately, take red cinchona bark, sarsaparilla, and
sage, of each 1 oz.; saffron, 1/2 oz.; rectified spirit, 32 oz.; digest
for 48 hours, and filter; mix the two liquors; add to them twice their
weight of lime water. In gout; 2 fl. oz. are sprinkled on the surface of a
hot linseed-meal poultice sufficiently large to surround the affected
part. It is said that the Emperor Napoleon gave £2500 for this receipt.
=Poultice of Pyroligneous Acid.= (Dr Reece.) _Syn._ CATAPLASMA ACIDI
PYROLIGNOSI. _Prep._ Bran, 1 lb.; linseed meal, 1 oz.; impure pyroligneous
acid, q. s. For scrofulous ulcers; occasionally 30 minims of tincture of
perchloride of iron, and 3 dr. of extract or powder of hemlock, are added.
=Poultice of Red Wine.= (Gl. Hosp.) _Syn._ CATAPLASMA VINI RUBRI. _Prep._
Linseed meal, 1-1/2 oz.; boiling water, 5 oz.; stir it over a slow fire
for a minute, remove, and add 2 oz. of red wine.
=Poultice, Roasted Apple.= _Syn._ CATAPLASMA MALI. The soft pulp of
roasted apple, applied to inflamed eyes. Other ingredients are sometimes
added.
=Poultice, Rose.= _Syn._ CATAPLASMA ROSÆ. _Prep._ Powdered alum, 30 gr.;
confection of roses, 4 oz.; mix.
=Poultice of Sea-wrack.= (Dr Russell.) _Syn._ CATAPLASMA FUCI. _Prep._
Fresh bladder fucus (sea-wrack) bruised. Applied to glandular tumours, &c.
=Poultice, Sim′ple.= _Syn._ CATAPLASMA SIMPLEX, L. _Prep._ (Ph. D. 1826.)
Powder for a cataplasma and boiling water, of each q. s. to form a
poultice, the surface of which is to be smeared over with olive oil.
Emollient. Bread poultice and linseed-meal poultice are now generally
called by this name. See POWDER (Poultice).
=Poultice of Slippery Elm.= CATAPLASMA ULMI. The powdered bark of the
slippery elm (_Ulmus fulva_) mixed with a sufficient quantity of hot
water.
=Poultice of Soap.= _Syn._ CATAPLASMA SAPONIS, L. _Prep._ From white soap
(scraped or sliced), 1 oz.; boiling water, 1/4 pint; dissolve, and add
crum of bread, q. s. As an application to scalds and burns.
=Poultice, Sorrel.= _Syn._ CATAPLASMA OXALIS. _Prep._ Bruised sorrel
leaves, mixed with oatmeal and beer.
=Poultice, Stimulating.= (Dr Hugh Smith.) _Syn._ CATAPLASMA STIMULANS.
_Prep._ Rye flour, 1 lb.; old yeast, 4 oz.; common salt, 2 oz.
=Poultice, Sulphate of Lime.= (Blizard.) _Syn._ CATAPLASMA CALCIS
SULPHATIS. _Prep._ Paris plaster mixed with water to a soft paste, and
applied before it hardens. Formerly applied to ulcers to form an
artificial scab; now occasionally used to afford mechanical support in
some surgical cases.
=Poultice of Sulphate of Soda.= (Kirkland.) _Syn._ CATAPLASMA SODÆ
SULPHATIS. _Prep._ Sulphate of soda, 1 oz.; boiling water, 1/2 lb.; crum
of bread, a sufficient quantity.
=Poultice to cause Suppuration.= (E. Ph. 1774.) _Syn._ CATAPLASMA
SUPPURANS. To an emollient cataplasm add bruised onions, 1-1/2 oz.;
basilicon ointment, 1 oz.
=Poultice of Tannate of Lead.= (G. Ph.) _Syn._ CATAPLASMA AD DECUMBITUM;
PLUMBUM TANNICUM PULTIFORME. _Prep._ Boil 2 oz. Of oak bark in sufficient
water to yield 10 oz. of strained decoction; add to this 1 oz. (by weight)
of liquid subacetate of lead, collect the precipitate on a filter, and put
it into a bottle with 2 dr. of rectified spirit.
=Poultice, Tonic.= (G. Hosp.) _Syn._ CATAPLASMA TONICUM. _Prep._ Powdered
bark, 1 oz.; charcoal, 1 oz.; camphor, 1-1/2 dr.; oil of turpentine, q. s.
=Poultice, Turnip.= _Syn._ CATAPLASMA RAPI. _Prep._ Peel turnips, boil
them till soft, beat them to a pulp, and apply warm.
=Poultice, Turpentine.= (Dr Reece.) _Syn._ CATAPLASMA TEREBINTHINÆ.
_Prep._ Oil of turpentine, 2 dr.; olive oil, 1 oz.; linseed meal, 1 oz.;
oatmeal, 4 oz.; boiling water, q. s. To indolent ulcers, and, with more
turpentine, to deep burns, scalds, and chilblains.
=Poultice of Vin′egar.= _Syn._ CATAPLASMA ACETI, L. _Prep._ From crum of
bread soaked in vinegar. Applied cold in bruises, extravasations, &c.,
especially black eyes. Verjuice is often employed in the same way.
=Poultice of Walnut Leaves.= (Perfect.) _Syn._ CATAPLASMA JUGLANDIS.
_Prep._ The fresh leaves of walnut bruised and mixed with honey. Applied
over the abdomen as a vermifuge.
=Poultice of Yeast.= _Syn._ CATAPLASMA FERMENTI (B. P., Ph. L.), C. F.
CEREVISIÆ, L. _Prep._ 1. (Ph. L.) Beer yeast and water at 100° Fahr., of
each 5 fl. oz.; mix, stir in flour, 1 lb., and place it near the fire
until it rises. In gangrenous or foul ulcers; to correct the fetor of the
discharge, and to hasten the sloughing.
2. (B. P.) Beer yeast, 6; flour, 14; water (at 100° Fahr.), 6; mix. Place
the mass near the fire till it rises.
=POUL′TRY.= Domestic birds, which are propagated and fed for the table,
and for their eggs, feathers, &c.
The poultry of this country are the common domestic fowl, the turkey, the
duck, and the goose; to which some writers add the guinea-fowl and the
peacock. Of these, the first is the most generally useful. Though a native
of India, it accompanies man through almost every gradation of
civilisation and climate, and flourishes almost everywhere, when properly
secured from the inclemency of the weather, and allowed an ample supply of
fresh air, with proper food. For the production of abundance of eggs it
must, however, be well fed and warmly lodged. The hen-roosts and
poultry-houses should be well protected from the weather, and their
temperature should be duly maintained by proximity to the stables,
cow-houses, or dwelling-house, and, in cold weather, by the employment,
when necessary, of artificial heat. The food should also contain an ample
supply of nitrogenous matter, for without this how can it be expected that
hens can produce abundance of eggs, which are peculiarly rich in nitrogen?
The ‘greaves’ of the tallow-chandlers, and such-like substances, are hence
excellent additions to the ordinary food of poultry. But it is not
sufficient merely to supply poultry with abundance of food and warmth; it
is equally necessary that they should have ample space for exercise and
recreation. This space “should always contain living plants of various
kinds, and some gravelly or sandy soil; because worms, snails, as well as,
occasionally, grass and herbage, form a part of the food of poultry; and
sand or gravel is swallowed by them for the purpose of promoting
digestion. Hence, no healthy poultry can ever be reared in towns, however
much the natural food may be imitated by the supply of animal matters,
herbage, and sand.” (Loudon.)
=POUNCE.= Powdered gum sandarac generally passes under this name. It is
used to prepare parchment for writing on, and to prevent ink from
spreading upon paper after erasures. Powdered cuttle-fish bone is
occasionally employed in the same way. Both are applied to the surface by
means of a cylindrical roll of list called a ‘rubber.’ Packers rub the
surface of porous and greasy woods, as the heads of boxes, cases, casks,
&c., with whiting or powdered resin, to make them bear the ink. The
coloured powders used by pattern drawers, for sprinkling over pricked
papers, are also called ‘pounce.’ For liquid pounce, see MARKING INK.
=POWDER.= _Syn._ PULVIS, L. Powders are divided by pharmaceutical writers
into two classes——simple and compound. The first are prepared by simple
pulverisation; the second by the admixture of two or more simple powders.
For use the appropriate doses are separately weighed, and placed in
separate papers. They are usually exhibited in a little honey, sugar, or
milk, either taken from a spoon or made into an electuary or bolus, and
swallowed in the semi-solid form. Metallic and other heavy powders are
best taken in the latter state. Very active substances should be, in all
cases, mixed with some inert powder, as that of starch, gum, liquorice, or
marshmallow, at the time of ‘dispensing’ them.
“This form of preparing medicines is the simplest, and perhaps the least
objectionable; but it is not applicable to all the articles of the Materia
Medica. Those remedies which are very unpleasant to the taste; those which
deliquesce rapidly when exposed to the air, or are very volatile; and
those which require to be given in very large doses, or which are not
diffused readily in water, cannot, with propriety, be administered in the
form of powder. Some substances cannot be reduced to powder unless they be
very much dried, and the heat necessary for that purpose alters their
properties.” Nor can we “be surprised that a great alteration should be
effected in a short time by the action of the air on so great an extension
of surface as takes place in the operation usually adopted for reducing
drugs to a fine powder.” (A. T. Thomson.)
In this country compound powders appear to be a favourite form of medicine
in the diseases of infancy and childhood.
“It is necessary that whatever we order to be reduced to powder should be
rubbed through a fine sieve, so that the impurities and coarser parts may
be separated; and it is needful that most powders should be recently
prepared, and not too long kept.” (Ph. L.)
As nearly all powders suffer by exposure to the air and light, they should
be preserved in closely-corked opaque or green-glass bottles, or in tin
canisters from which the external air is carefully excluded. See
PULVERISATION, &c.
=Powder, Algaroth’s.= See ANTIMONY, OXYCHLORIDE.
=Powder of Al′oes (Compound).= _Syn._ PULVIS ALOËS COMPOSITUS (Ph. L.), P.
ALOËS CUM GUAIACO, L. _Prep._ (Ph. L.) Socotrine or hepatic aloes (in
powder), 1-1/2 oz.; guaiacum (in powder), 1 oz.; compound cinnamon powder,
1/2 oz.; rub them together. A warm, sudorific purgative.——_Dose_, 10 to 20
gr.
=Powder of Aloes with Canel′la.= _Syn._ ALOETIC POWDER, HOLY BITTER†;
HIERA PICRA†, PULVIS ALOES CUM CANELLÂ, L. _Prep._ From powdered Socotrine
or hepatic aloes, 4 parts; powdered white canella, 1 part. Uses and dose,
as the last.
_Obs._ Once a highly popular remedy. It was originally made into an
electuary with honey, and in this form was frequently called ‘HIERA
LOGADII,’ It is still a favourite in domestic medicine and veterinary
practice. The principal objection to both this and the preceding
preparation is the nauseous flavour of the aloes, which is ill concealed
by the aromatics. The ‘HIERA PICRA’ for farriers is usually made with the
cheapest Cape aloes.
=Powder of Aloes with Iron.= (L. Ph. 1788.) _Syn._ PULVIS ALOETICUS CUM
FERRO. _Prep._ Aloes, 1-1/2 oz.; myrrh, 2 oz.; sulphate of iron, 1 oz.;
dried extract of gentian, 1 oz.
=Powder of Al′um (Compound).= _Syn._ STYPTIC POWDER; PULVIS STYPTICUS, P.
ALUMINIS COMPOSITUS (Ph. E.), L. _Prep._ (Ph. E.) Alum, 4 oz.; kino, 1
oz.; mix them, and reduce them to fine powder. Astringent and
styptic.——_Dose_, 5 to 15 gr.; in diarrhœa, profuse menstruation, &c.
Externally, in hæmorrhages, &c.
=Powder, Alum, Opiated.= (Bouchardat.) _Syn._ PULVIS ALUMINIS OPIATUS.
_Prep._ Alum, 1 dr.; sugar, 1 dr.; opium, 4 gr.; mix for 12 powders. 2 or
3 daily in obstinate diarrhœas and passive hæmorrhages.
=Powder of Alum with Capsicum.= (Dr Turnbull.) _Syn._ PULVIS ALUMINIS CUM
CAPSICO. _Prep._ Alum, 3 parts; concentrated tincture of capsicum, 1 part;
mix, dry, and triturate again. Applied to the tonsils.
=Powder of Alum with Gum.= (Frankel.) _Prep._ Alum, gum tragacanth, of
each equal parts. Applied to sore breasts.
=Powder of Alum with Starch.= (St. Th. Hosp.) _Syn._ PULVIS ALUMINIS CUM
AMYLO. _Prep._ Alum and starch, equal parts. In insufflation of
rhinorrhœa.
=Powder of Ambergris with Musk.= (Bat. Ph.) _Syn._ PULVIS AMBERGRISEÆ
MOSCHATUS. _Prep._ Ambergris, 6 dr.; musk, 1 dr.; oil of cinnamon, 2
scruples; refined sugar, 11-1/2 oz.; mix.
=Powder, Ammoniated Aromatic.= _Syn._ PULVIS AMMONIATUS AROMATICUS;
LEAYSON’S AMMONIACAL COLLYRIUM. _Prep._ Muriate of ammonia, 1 dr.; slaked
lime, 1 oz.; charcoal, 15 gr.; cinnamon, 15 gr.; cloves, 15 gr., bole, 1/2
dr. Put them into a bottle and moisten with a little water.
=Powder of Ancho′vy.= _Syn._ PULVIS CLUPEÆ ENCRASICOLI, L. _Prep._ Pound
anchovies to a paste, then rub them through a sieve, and add enough flour
to make a dough, which must be rolled out into thin slices and dried by a
gentle heat in a stove; it is, lastly, powdered and bottled. Colouring is
frequently added. Chiefly used to make sauces. British anchovies are
frequently substituted for the genuine fish.
=Powder, Anthrakokali, Compound.= _Syn._ PULVIS ANTHRAKOKALI, COMPOUND.
_Prep._ Anthrakokali, 2 gr.; washed sulphur, 6 gr.; mix. For 1 dose.
=Powder, Anthrakokali, Simple.= (Poyla.) _Syn._ PULVIS ANTHRAKOKALI
SIMPLEX. _Prep._ Anthrakokali, 2 gr.; liquorice powder, 6 gr.; mix. For 1
dose.
=Powder, Antiepileptic.= _Syn._ PULVIS ANTIEPILEPTICUS (E. Ph., 1744.)
_Prep._ White dittany, pæony, valerian, mistletoe of the oak, equal
parts.——_Dose_, 10 to 6 gr. (Behrends.) _Prep._ Valerian, 4 dr.; magnesia,
muriate of ammonia, oil of cajeput, of each 1 scruple.——_Dose._ A
teaspoonful three times a day. Dr Paris says the following was used
successfully by a Dutch empiric:——Sulphur, 1 scruple; sulphate of potash,
10 gr.; rhubarb, 5 gr.; nutmeg, 2 gr.; mix. (Germ. Hosp.) _Prep._ Oxide of
zinc, 16 gr.; carbonate of magnesia, 48 gr.; oleo-saccharum of cajeput, 3
dr. Mix for 8 doses. _Poudre de Ragolo._ Oxide of zinc, 10 gr.; valerian,
mistletoe, sugar, orange leaves, of each 4 dr.; magnesia, 2 scruples; oil
of cajeput, 2 scruples; a teaspoonful three times a day. Pasquier
prescribes——Wall crop, 10 gr.; gum Arabic, 10 gr.; 1 to 4 powders daily
for eight times. SOMMER’S SPECIFIC consists of——Wall crop, 6 to 10 gr.;
oleo-saccharum of mint, 8 gr.; one morning and evening for six times. See
PULVIS ARTEMISIÆ SACCHARATUS. The _Poudre de Guttète_ consists of
mistletoe, 2 parts; white dittany, 2; pæony root and seeds, 2; prepared
coral, 1; elk’s hoof, 2; seeds of orache, 2. Given in doses of a few
grains in convulsions of infants, or in larger doses for epilepsy.
=Powder, Antihydrophobic.= (Dr Mead.) _Syn._ PULVIS ANTILYSSUS. _Prep._
Ash-coloured ground liver-wort (_Pettidea canina_), 1/2 oz.; black pepper,
2 dr.; mix, and give a fourth part every morning for 4 times.
=Powder, Antimo′′nial.= _Syn._ FEVER POWDER, LISLE’S P., JAMES’S P.;
PULVIS JACOBI, PULVIS ANTIMONIALIS (B. P., Ph. E., & D.), PULVIS ANTIMONII
COMPOSITUS (Ph. L.), L. _Prep._ 1. (Ph. L.) A mixture of tersulphide of
antimony, 1 lb., and hartshorn shavings, 2 lbs., is reduced to powder,
thrown into a crucible heated to whiteness, and stirred constantly until
vapour no longer rises; the calcined mixture is then rubbed to powder,
again put into the crucible, and the heat gradually increased to
whiteness, and maintained so for 2 hours; the residuum is, lastly, reduced
to a very fine powder.
2. (Ph. E.) From sulphide of antimony and hartshorn shavings, equal
weights; as the last.
3. (Ph. D.) Tartarised antimony, 4 oz., is dissolved in water, 1/2 gall.,
and added to solution of phosphate of soda, 4 oz., in water, 1 quart; a
solution of chloride of calcium, 2 oz., in water, 1 quart, and to which
solution of ammonia (Ph. D.), 4 fl. oz., has been added, is next poured
in, and the whole boiled for 20 minutes; the precipitate is then collected
on a calico filter, and washed with hot distilled water, until the liquid
which passes ceases to give a precipitate with a weak solution of nitrate
of silver; it is, lastly, dried by a steam or water heat, and reduced to a
fine powder.
4. (B. P.) Oxide of antimony, 1; precipitated phosphate of lime, 2;
mix.——_Dose_, 2 to 6 gr.
_Uses, &c._ Febrifuge and diaphoretic. Intended as a substitute for the
proprietary and more expensive JAMES’S POWDER.——_Dose_, 3 to 10 or 12 gr.,
or more, repeated every fourth or fifth hour until diaphoresis is set up;
in fevers, rheumatic affections, chronic skin diseases, &c. It is a very
uncertain and variable compound, unless it has been carefully prepared. Dr
Elliotson exhibited it in doses of 100 gr. without producing any sensible
effect. A spurious article, made by triturating 1 oz. of tartar emetic
with 18 or 19 oz. of burnt hartshorn, is frequently sold for it in the
shops. See ANTIMONIOUS ACID and JAMES’S POWDER.
=Powder, Antispasmodic.= (P. Cod.) _Syn._ PULVIS ANTISPASMODICUS. _Prep._
Cyanide of zinc, 3 gr.; calcined magnesia, 24 gr.; cinnamon, 12 gr.; mix.
For 6 doses.
=Powder, Antispasmodic.= (Jourdan.) _Syn._ PULVIS ANTISPASMODICUS. _Prep._
Valerian, 1 oz.; oxide of zinc, 1 scruple; musk, 8 gr.; mix.
=Powder, Aromat′ic.= See POWDER, COMPOUND CINNAMON.
=Powder, Arsen′ical.= See POWDER, ESCHAROTIC.
=Powder of Asarabac′ca (Compound).= See SNUFF (Cephalic).
=Powder, Astrin′gent.= _Syn._ PULVIS ASTRINGENS, P. STYPTICUS, L. _Prep._
1. From Aleppo galls and burnt alum, in fine powder, equal parts. Used in
piles, soft polypi of the nose, chilblains, &c.
=Powder, Ba′′king.= _Prep._ 1. Tartaric acid, 1/2 lb.; bicarbonate of soda
and potato farina or British arrow-root, of each 3/4 lb. (each in powder);
separately dry them perfectly by a very gentle heat, then mix them in a
dry room, pass the mixture through a sieve, and at once put it into
packets, observing to press it hard, and to cover it with tinfoil or
close-made paper, to preserve it as much as possible from the air and
moisture.
2. (Delforte’s.) Powdered tartaric acid, 1/4 lb.; powdered alum, 1/2 lb.;
bicarbonate of soda, 3/4 lb.; farina, 1 lb.; dry separately, as before,
mix, and further add of sesquicarbonate of ammonia (in powder), 3 oz.;
lastly, closely pack it in tinfoil.
3. (Green’s.) Tartaric acid, 35 lbs.; sesquicarbonate of soda, 56 lbs.;
potato flour, 1 cwt.; mix as before.
_Uses, &c._ Baking powder is chiefly employed as a substitute for yeast. 1
or 2 teaspoonfuls are mixed with the dry flour and other ingredients,
which are then made into a dough, as quickly as possible, with cold water,
and at once baked or boiled as the case may be. By the addition of about
1/2 dr. of turmeric powder to each pound of the mixture it is converted
into egg powder. When intended to be kept for any length of time it should
be preserved in bottles or tins, so as to prevent the absorption of
moisture. We have discovered traces of arsenic in some of the baking
powders of the shops, which we refer to common washerwoman’s soda being
used in their composition, instead of the pure carbonate or
sesquicarbonate.
=Powder, Basil′ic.= _Syn._ ROYAL POWDER, CORNACHINI’S P.; PULVIS
BASILICUS, P. CORNACHINI, L. _Prep._ From scammony, calomel, cream of
tartar, and diaphoretic antimony, equal parts. This is the formula
generally adopted for this compound, which has now long been omitted from
the Pharmacopœias. It is still a favourite with many practitioners, as an
alterative purgative, and vermifuge for children.——_Dose._ For a child, 2
to 8 gr.; for an adult, 5 to 20 gr. Compound powder of scammony is now
generally sold for it.
=Powder, Belladonna, Saccharated.= (Wertzler.) _Syn._ PULVIS BELLADONNÆ
SACCHARATUS. _Prep._ Belladonna root, 15 gr.; pure sugar, 1 dr.; mix. For
72 powders. One twice a day, or oftener, according to the age. In
hooping-cough.
=Powder, Blaine’s Distem′per.= The basis of this preparation is the ‘aurum
musivum,’ or bisulphuret of tin. (Dr Paris.)
=Powder, Blancmange′.= _Prep._ From sago meal, 1 lb.; essence of lemon, 15
drops; mace, 12 gr.; mix.
=Powder, Bleaching.= Chloride or hypochlorite of lime.
=Powder, Blue.= See SMALTS.
=Powder, Bronze.= See STANNIC SULPHIDE, BRONZING, &c.
=Powder of Burnt Hartshorn.= _Syn._ PULVIS CORNU CERVINI USTI, L. _Prep._
From pieces of hartshorn calcined to whiteness, and powdered. It consists
principally of phosphate of lime.——_Dose_, 10 to 30 gr.; in rickets, &c.
=Powder of Burnt Hartshorn with O′pium.= _Syn._ PULVIS OPIATUS, PULVIS
CORNU USTI CUM OPIO, L. _Prep._ From powdered calcined hartshorn, 1 oz.;
powdered opium and cochineal, of each 1 dr.——_Dose_, 5 to 20 gr.
=Powder of Camphor.= Camphor may be readily pulverised by triturating it
with the addition of a few drops of rectified spirit or ether.
=Powder, Camphorated Nitre.= (Swediaur.) _Syn._ PULVIS NITRO CAMPHORATUS.
_Prep._ Nitre, 10 gr.; camphor, 4 gr.; gum Arabic, 24 gr.; mix. For two or
three doses.
=Powder, Capuchin′.= _Prep._ From powdered cevadilla, parsley seed,
stavesacre, and tobacco, equal parts. Used to destroy pediculi.
=Powder, Castillon’s.= _Prep._ From sago meal, salep, and gum tragacanth,
of each 3 dr.; prepared oyster shells, 1 dr.; cochineal, q. s. to colour.
Absorbent.——_Dose_, 1/2 to 1 dr., boiled in milk; in diarrhœa, &c.
=Powder of Cat′echu (Compound).= _Syn._ PULVIS CATECHU COMPOSITUS (B. P.,
Ph. D.), L. _Prep._ 1. (Ph. D.) Take catechu and kino, of each 2 oz.;
cinnamon and nutmeg, of each 1/2 oz.; reduce each to a fine powder, mix,
and keep the prepared powder in a well-stopped bottle. Aromatic and
astringent.——_Dose_, 1/4 dr. to 2 dr.; in various affections.
2. (B. P.) Pale catechu; kino, 2; rhatany, 2; cinnamon, 1; nutmeg, 1;
mix.——_Dose_, 15 to 30 gr.
=Powder of Chalk (Compound).= _Syn._ PULVIS CRETÆ AROMATICUS (B. P.),
PULVIS CRETÆ COMPOSITUS (Ph. L., E., & D.), P. CARBONATIS CALCIS COMP., L.
_Prep._ 1. (Ph. L.) Prepared chalk, 1/2 lb.; cinnamon, 4 oz.; tormentil
and gum acacia, of each 3 oz.; long pepper, 1/2 oz.; rub them, separately,
to a very fine powder, and mix them.
2. (Ph. E.) Prepared chalk, 4 oz.; cinnamon, in fine powder, 1-1/2 dr.;
nutmeg, in fine powder, 1 dr.
3. (Ph. D.) Prepared chalk, 5 oz.; cinnamon, 2-1/2 oz.; gum, 2 oz.;
nutmeg, 1/2 oz.
4. (AROMATIC POWDER OF CHALK——B. P.) Chalk, 11; cinnamon, 4; nutmeg, 3;
saffron, 3; cloves, 1-1/2; cardamom seed, 1; refined sugar, 25; all in
powder; mix.——_Dose_, 30 to 60 gr.
_Uses, &c._ Aromatic, astringent, and antacid.——_Dose_, 10 to 30 gr.; in
acidity, flatulence, heartburn, diarrhœa, &c. The following form is used
by many wholesale houses:——Prepared chalk, 4 lbs.; powdered cassia, 2
lbs.; powdered calamus aromaticus, 3/4 lb.; powdered gum, 1-1/2 lb.; long
pepper, 1/4 lb.
=Powder of Chalk with Opium (Compound).= _Syn._ PULVIS CRETÆ AROMATICUS
CUM OPIO (B. P.); OPIATED CHALK POWDER; PULVIS CRETÆ COMPOSITUS CUM OPIO
(Ph. L.), PULVIS CRETÆ OPIATIS (Ph. E. & D.), L. _Prep._ 1. (Ph. L.)
Compound chalk powder, 6-1/2 oz.; powdered opium, 80 gr.
2. (Ph. E.) Compound chalk powder, 6 oz.; powdered opium, 80 gr.
3. (Ph. D.) Compound chalk powder, 4 oz. 7 dr.; opium, in fine powder, 1
dr.
4. (Wholesale.) Compound chalk powder, 21 oz.; powdered opium, 1/2 oz.
Anodyne, antacid, and carminative.——_Dose_, 10 to 30 gr.; in the same
cases as the preceding, than which it is more active. It has long been a
favourite remedy in all cases of simple and even choleraic diarrhœa.
5. Aromatic powder of chalk (_see_ POWDER OF CHALK (Compound), 4), 39;
opium, in powder, 1; mix thoroughly, and pass through a sieve.——_Dose_, 10
to 40 gr.
=Powder, Chalk Mixture.= _Syn._ PULVIS PRO MISTURA CRETÆ, L. _Prep._
(Beasley.) Powdered gum acacia, 5 oz.; prepared chalk, 4 oz.; white sugar,
3 oz.; oil of cinnamon, 1-1/2 fl. dr.; mix. 40 gr. of this powder,
triturated with 1 fl. oz. of water.
=Powder, Chol′era (Saline).= _Syn._ PULVIS SALINUS ANTICHOLERICUS, L.
_Prep._ 1. (Dr O’Shaughnessy.) Carbonate of soda, 5 gr.; chloride of
sodium, phosphate of soda, and sulphate of soda, of each 10 gr. For a
dose.
=Powder of Cin′namon (Compound).= _Syn._ AROMATIC POWDER; PULVIS CINNAMOMI
COMPOSITUS (B. P., Ph. L.), PULVIS AROMATICUS (Ph. E.), L. _Prep._ 1. (Ph.
L.) Cinnamon, 2 oz.; cardamoms, 1-1/2 oz.; ginger, 1 oz.; long pepper, 1/2
oz.; rub them together so that a fine powder may be made.
2. (B. P., Ph. E.) Cinnamon, cardamom seeds, and ginger, equal parts; to
be kept in a well-closed glass vessel.
3. (Ph. D.) Cinnamon and ginger, of each 2 oz.; cardamom seeds (husked),
and nutmegs, of each 1 oz. Aromatic and carminative.——_Dose_, 10 to 30 gr.
In the powder of the shops cassia is generally substituted for cinnamon.
=Powder, Cla′rifying.= Flake albumen. See ALBUMEN.
=Powder, Cock′le.= From the well-known shell-fish _Cardium edule_ (Linn.),
as oyster powder.
=Powder, Colbatche’s Specific.= _Prep._ From solution of sesquichloride of
iron and acetate of lead, of each 4 oz.; mix, evaporate to dryness, powder
the residuum, and preserve it from the air. Astringent and
hæmostatic.——_Dose_, 3 to 8 grs.