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with water ; dilute acetic acid is slowly and cautiously added, till it
dissolves no more of the morphine even after prolonged contact ; and
the filtrate is evaporated in shallow vessels between 38 and 50,
preferably in a current of air, since the salt is decomposed by gradual

evaporation (Merck). By Kukle's method (Saumgartner's Zeitschr. f. Phys.
4, 182), which consists in dissolving morphine in alcoholic acetic acid and covering the
solution with a large quantity of ether, a mixture of morphine and acetate of mor-
phine is obtained, not completely soluble in ether (Merck, Ann. Pharm. 24, 46).

White silky needles grouped in tufts or cauliflower-like masses (Sertiir-
ner, Merck). Very bitter (Geiger). Neutral (Merck). When the solution
is quickly evaporated, the salt remains as a colourless, transparent



MORPHINE. 435

varnish (Braconnot, Geiger). The aqueous solution, when repeatedly
evaporated by heat, loses a small portion of its acid, so that the
residue is no longer completely soluble in water (Pellctier, J. Pharm. 9,
523, Geiger). The alcoholic solution mixed with a large quantity of
ether, gives up to the ether a portion of the acid, so that morphine crys-
tallises out (Merck). Deliquescent (0. Henry, J. Pharm. 21, 226). Dis-
solves in 24 parts of water at 18f (Abl, Oesterr. pharm. Zeitschr. 8,
201). Dissolves freely in water, less easily in alcohol (Buchholz), not
at all in ether (Geiger). Soluble hi 60 parts chloroform (Schliinpert).
Contains 79*8 p. c. morphine ; corresponding to the formula
C*NH 19 6 ,C 4 H 4 4 + 2Aq ( Calculation gives 79 . 2 p . c . c^NH^O 6 ) (Kieffer.)



Cyanurate of Morphine. Tufts of long needles, mixed with crystals
of cyanuric acid, even when morphine is present in excess. It is
decomposed by recrystallisation, with formation of a white amorphous
mass (Elderhorst, Ann. Pharm. 74, 84).

Mellitate of Morphine. a. Bibasic ? When cold aqueous mellitic
acid is saturated with morphine and the solution evaporated, there
remains a brown, amorphous, brittle mass (Karmrodt).

b. Monobasic. The solution of morphine in hot concentrated
aqueous mellitic acid soon deposits white, microscopic, needle-shaped
crystals, which give off 2 p. c. of their weight at 110. They are
rather more soluble in cold than in hot water, freely in aqueous
ammonia and potash, not in alcohol or in ether (Karmrodt, Ann. Pharm.
81, 171).

Karmrodt.

mean.
C 34 NH i9O,2HO ........................ 303 ........ 75-94 ........

C S O 6 ............................................ 96 ' ........ 24-06 ........ 24-90

C 34 NH 19 O 6 ,C 8 H 2 O 8 .................... 399 ........ 100-00 ........

Aspartate of Morphine. Gum containing shining crystals. Very
freely soluble hi water (Plisson, J. Pharm. 15, 274).

Tartrate of Morphine. a. Neutral. When a solution of cream of tartar
is neutralised with morphine, cream of tartar crystallises out first, then
nodules of the morphine-salt, which must be removed in time, so as to
keep them separate from the neutral tartrate of potash which after-
wards crystallises out. The salt may be also obtained by slow evapora-
tion of an aqueous solution of tartaric acid neutralised with morphine
Nodular groups of crystals consisting of closely aggregated needles.
Effloresces on the surface at 20 ; loses on the average 6'54 p. c.
water at 130 (2C 34 NH 19 O 6 ,C 8 HO 12 + Aq. = 676 p. c. HO) no more at 145.
Exhibits crystal electricity (i. 319) when heated to 130 or 140, and
retains it for an hour after cooling. Soluble in alcohol. The easily
formed aqueous solution is riot precipitated by caustic alkalis, alkaline
carbonates, chloride of calcium, or ammonio-chloride of calcium (Arppe,
J. pr. Chem. 53, 332).

b. Acid. The solution a. is mixed with as much tartaric acid as it
already contains, and allowed to evaporate slowly. Flat rectangular
prisms which lose about 2 p. c. water below 140 (C 34 NH 19 O 6 ,C 8 H G O :2 +
Aq. = 1-98 p. c. HO) caking together slightly at the same time and

2 F 2



436 PRIMARY NUCLEUS C M IF 4 ; OXYAZO-NUCLEUS

becoming- somewhat browned. In small quantities they are fusible
without decomposition. Less soluble in water than a. (Arppe).

Urate of Morphine. Obtained by boiling uric acid and morphine
with water. Crystallises on cooling from a solution saturated at the
boiling heat, in short brownish prisms which decompose when re-
crystallised (Elderhorst).

Croconate of Morphine. Bark-yellow, uncrystallisable, bitter mass,
soluble in water and in alcohol (Heller, J. pr. Chem. 12, 240).

Rhodizonate of Morphine. Hyacinth-red ; soluble, with reddish-
yellow colour, in water and in alcohol (Heller).

Valerate of Morphine. Fine large hemihedral crystals belonging
to the right prismatic system, with a fatty lustre on the faces. Smells
strongly of valerianic acid. Rhombic prism (Fig. 53) having the
obtuse lateral edge symmetrically truncated by p, the dome u resting
on the acute lateral edges, and the octahedron a occurring only hemi-
hedrally. u : u above = 125 47' , a : y = 130 0' , a: u = 148 28';
the acute lateral edges of y are sometimes bevelled by a prism of
10-2 8' (Pasteur, N. Ann. Chim. Phys. 38, 445).

Pyrotartrate of Morphine. Fissured gum, soluble in water and in
alcohol (Arppe).

Picric acid forms with morphine-salts, a sulphur-yellow pulverulent
precipitate (v. Planta) ; no precipitate with dilute acetate of morphine
(Merck). Alcoholic picric acid does not x precipitate alcoholic morphine
(G. Kemp, Repert. 71, 164).

Hippurate of Morphine. A hot saturated aqueous solution of
hippuric acid does not yield any crystals after boiling with excess of
morphine, but leaves on evaporation a syrup, which hardens to a
transparent amorphous mass (Elderhorst).

Morphine-salts are not precipitated by gallic acid free from tannin
(Pettenkofer, Pfaff).

.Meconate of Morphine. Not crystallisable ; very soluble in water
and in alcohol. Eeddens iron-salts (Robiquet, Liebig). It is present
in the aqueous extract of opium.

Pectate of Morphine. Recently precipitated pectic acid dissolves
morphine even in the cold, forming a thick gum, which, after dilution
with water, is thickened again by acids (Braconnot).

Kinate of Morphine. Transparent gum exhibiting traces of
crystallisation (Henry & Plisson, J. Pharm. 15, 406).

Tannate of Morphine. Morphine-salts form a white precipitate
with tincture of galls (Pettenkofer), and with tannic acid (Pelouze) ;
even when diluted 900 times (0. Henry, J. Pharm. 21, 212). The
precipitate is but sparingly soluble in water, freely in acetic acid, gallic
acid (Pelouze), and mineral acids (Duflos). It is soluble in alcohol
(Dublanc). If the morphine-salt contains free acid, no precipitate is
formed ; sometimes even neutral hydrochlorate of morphine gives no
precipitate until a trace of ammonia is added (Robiquet, J. Pharm. 25,
82). In dilute solutions of morphine-salts, a small quantity of tincture
or infusion of galls produces a turbidity, which disappears on addition
of a drop of hydrochloric acid, and reappears when more is added, if
the tincture, and not the infusion of galls is used (v. Plauta).



MORPHINE. 437

C. With Alkalis. Morphine dissolves in 117 parts of aqueous
ammonia of sp. gr. O97 (Merck), remaining in crystals when the solu-
tion is evaporated (Duflos, Merck). Recently precipitated morphine
dissolves in excess of carbonate and hydrochlorate of ammonia, but
less freely than in pure ammonia (Riegel, Fresenius). Morphine or its
acetate dissolves in an ammoniacal solution of oxide of copper, sepa-
rating the hydrated oxide ; since the compound of ammonia and
morphine which is formed easily loses ammonia, the solution continually
deposits morphine, which again precipitates hydrated oxide of copper
(Kieffer).

Aqueous solutions of potash or soda dissolve morphine very freely,
and deposit it in crystals when exposed to the air, in proportion as they
absorb carbonic acid (Robinet, Wittstock). The solution may be pre-
cipitated by acetic acid (Bracormot), also by the alkaline bicarbonates,
and by sal-ammoniac.

A solution of morphine in baryta-water when exposed to the air,
deposits a mixture of morphine and carbonate of baryta (Robinet).
Warm lime-water dissolves morphine freely, forming a bitter liquid,
which is precipitated by acids (Braconnot), and when exposed to the
air, deposits morphine and carbonate of lime (Robinet).

D. With Organic oxides. According to Choulant, morphine dissolves
in 42 parts of cold or 36 parts of boiling alcohol; according to Buchholz
& Brandes, in 24 parts boiling alcohol of 92 p. c. ; according to
Merck, in 90 parts of cold alcohol of 96 p. c. ; according to Pettenkofer,
in 40 parts of cold or 30 parts of boiling absolute alcohol ; according to
Duflos, in 20 parts of cold, or 13'3 parts of boiling absolute alcohol. The
solution in cold alcohol of 96 p. c. is not precipitated by water (Merck).

It is not soluble in cold or boiling ether (Duflos, Merck). Anhydrous
ether dissolves a small quantity of morphine, but if shaken up with
water, scarcely a trace ; recently precipitated morphine dissolves in ether
about three times as largely as the crystallised base (Petit). Ether
containing alcohol dissolves morphine (Folstorf). From aqueous mor-
phine (Petit), or from a solution of a salt of morphine supersaturated
with carbonate or bicarbonate of soda, ether extracts the morphine,
if shaken up with the liquid at once, but not if the morphine has been
allowed to become crystalline. Ether does not extract morphine from
solutions containing excess of potash or ammonia (A. Petit, N. J.
Pharm. 43, 45). Morphine is soluble in acetic ether (Valser, N. J.
Pharm. 43, 49).

Morphine dissolves in 60 pts. chloroform (Schlimpert, N. Jahrb.

Pharm. 13, 248), in 175 pts. (Pettenkofer, N. Jahrb. Pharm. 10, 270).

It is insoluble in glycerin (Cap and Garot, N. J. Pharm. 26, 81).

Very soluble in hot fusel-oil (J. Erdmann) ; insoluble in benzol (RodgerB,

Anal. Zeitschr. 1, 516), and infixed oils (Geiger ; Cap & Garot).

Morphine is rendered more soluble in water by addition of picrot-
oxine (Pelletier & Couerbe, Ann. Chim. Phys. 54, 186). See Brucine.
From its solution in acetic, sulphuric, or hydrochloric acid, not in excess,
it is precipitated by 5 to 7 pts. blood-charcoal, or ignited bone-black
(also from its alcoholic solution), but -not by moist bone-black which
has been purified by hydrochloric acid, and not re-ignited (Guthe).
When a hydrochloric acid extract of opium is boiled with animal charcoal till all the
morphine is precipitated, the washed and dried charcoal does not give up the
morphine till boiled for some time with a very large quantity of alcohol (Bley, N. Br.
Arch. 62, 162) . The same observation was made by Lefort.



438 CONJUGATED COMPOUNDS OF MORPHINE.

Conjugated Compounds of Morphine.

Sulphomorphide.

C 34 NH 1R S0 8 = C 34 NH I8 8 ,S0 3 .

ARPPE. Ann. Pharm. 55, 96.

LAURENT & GEKHARDT. A". J. Pharm. 14, 302 ; N. Ann. Chim. Phys.

24,112; abstr. Compt. rend. 27,80; J. pr. Chem. 45,369; Ann.

Pharm. 68, 359.

Formation. By heating morphine with excess of sulphuric acid, or
by passing the vapour of anhydrous sulphuric acid over effloresced
morphine.

Preparation. Sulphate of morphine is evaporated down with a
slight excess of sulphuric acid, the heat being ultimately raised to 150
or 160; the brown residue is treated with water, which separates a
white substance ; and the liquid is boiled till this substance is dissolved,
arid then filtered hot. On cooling, it deposits Sulphomorphide, a
further quantity of which may be obtained by boiling the yellowish
brown residue left on the filter, with addition of a little sulphuric acid.
It may be freed from adhering sulphuric acid by washing (Arppe).

Properties After drying it is whiter than before ; if it has been too
strongly heated with sulphuric acid, it has a brownish colour. Nori-
crystalline microscopic spherules (Arppe). Turns green, even when
kept in a sealed tube, also when heated to 130 150 (Laurent &
Gerhardt).









Arppe.


Laurent








mean.


& Gerhardt.


34 C


204 ....


.... 64-56 ....


... 61-17 ....


.... 63-0


N


14 ...


4-43 ....


3-96 ....




18 H


18 ..


5-69 . ..


5-69 ....


5-8


S


16


506 ....


5-76 ....


.... 5-4


8 O


. 64


20-26


.. . 23-42 ....















316 ........ 100-00 ........ 100-00 ........



According to Arppe, it contains 4 at. morphine to 5 at. sulphuric acid. Laurent
& Gerhardt double the formula above given. Differs from sulphate of morphine by
containing 2 at. less water, and is related thereto in the same manner as sulphate of
ammon (ii, 458) to sulphate of ammonia.

Decompositions. Sulphomorphide does not volatilise without de-
composition; when heated on platinum foil, it leaves a very bulky
cinder, difficult to burn (Laurent & Gerhardt). 2. The solution in
hot water acquires an emerald-green colour by boiling. 3. By con-
centrated acids or alkalis, it is decomposed, with formation of a brown
substance, but without reproduction of morphine (Arppe).

It appears to be slightly soluble in water. In water containing
hydrochloric or sulphuric acid it dissolves very easily, without alteration
and without forming salts. The acid solutions yield copious precipi-



ETHYL-MORPHINE. 439

tates with ammonia, potash, and carbonate of ammonia; an excess of
ammonia, but not of carbonate of ammonia, redissolves the pre-
cipitate, which turns green when exposed to the air. From the
solution in hydrochloric acid, baryta-salts throw down only part of the
sulphur as sulphuric acid (Arppe).
: Insoluble in alcohol and in ether.



Methyl-morphine.

C 3 NH 21 6 = C 34 N(C 2 H 3 )H 18 6 ,IP.

H. How. Chem. Soc. Qu. J. 6, 125 ; Ann. Pharm. 88, 338.
Formemorphin.

Obtained as a hydriodate by heating finely pulverised morphine for
half an hour to 100 in a sealed tube with absolute alcohol and iodide
of methyl. The crystalline powder which separates on cooling, is
collected and washed with alcohol, or crystallised from hot water.

From the warm aqueous solution of hydriodate of methyl-morphine,
oxide of silver separates iodide of silver, forming aqueous methyl-
morphine, which, when evaporated, leaves a brown translucent, amor-
phous mass. This mass is attacked by a mixture of iodide of methyl and alcohol,
even in the cold, with formation of brown flocks, and at 100, with formation of a
brown resin, but without yielding a hydriodate of bimethyl-rnorphine.

Hydriodate of Methyl-morphine. Colourless, shining, square pris-
matic needles which give off 4-15 p. c. water at 100 (2 at. = 4'04
HO). Easily soluble in hot water.



36 C


at 100.
216




50-57




How.
50-47


N


14




3-27 .






22 H


22




5-15 .




5-36


6 O


48




11-26 .






I ..


.. 127




29-75 .




29-66



C 34 N(C 2 H 3 )H 18 O 6 ,HI 427 100-00

Ethyl-morphine.
C^NH^O 2 = C 34 N(C 4 H 5 )H 16 6 ,H 2 .

II. How. Chem. Soc. Qu. J. 6, 125 ; Ann. Pharm. 88, 336.
Vinemorphin.

Obtained as a hydriodate, by heating finely pulverised morphine
with absolute alcohol and iodide of ethyl to 100 in a sealed tube for
six hours. The crystals which separate on cooling are collected and
washed with alcohol.

From the warm aqueous solution of hydriodate of ethyl-morphine,
oxide of silver separates iodide of silver, forming aqueous ethyl-
morphine. This solution assumes a dark brown colour as soon as the



440 APPENDIX TO MORPHINE.

hydriodate is completely decomposed ; it is strongly caustic, and
leaves, on evaporation, a solid, dark coloured, translucent residue,
which does not crystallise.

Hydriodate of Ethyl-morphine separates, on cooling from solution in
hot water, in slender white needles, which are permanent in the air,
and give off 1'98 p. c. water (= 1 at.) at 100. It is not decomposed
by potash or ammonia. It dissolves easily in hot water and in weak
spirit, but with difficulty in absolute alcohol.

at 100. How.

38 C 228 51-71 51-45

N 14 3-17

24 H 24 5-44 5'74

6O , 48 10-87

I 127 28-81 28-50

C 34 N(C 4 H 5 )H 18 6 ,HI.. 441 100-00



Appendix to Morphine.

1. Pseudomorphine.

PELLETIEE. J. Pharm. 21, 575; N. Br. Arch. 5, 169; Ann. Pharm.
16, 49.

Discovered in 1835 by Pelletier & Thiboumery. It was found,
but only three times, in opium, the aqueous extract of which contained
a large quantity of narcotine.

The morphine precipitated by ammonia from the aqueous infusion
of opium, still contained narcotine in these cases, even after repeated
crystallisation from alcohol ; it was therefore dissolved in soda-ley,
and filtered from the narcotine. After the alkaline solution had been
acidulated with sulphuric acid, precipitated by ammonia, and separated
from the precipitated morphine, it yielded, on concentration, whitish
scales of pseudomorphine containing sulphuric acid, which were re-
crystallised from boiling water. After this treatment, they still
retained 8'83 p. c. sulphuric acid, which could be extracted by boiling
them with ammoniacal water.

Pseudomorphine containing sulphuric acid forms scales having a
pearly lustre ; when free from sulphuric acid, it forms dull scales.
Cannot be melted or sublimed. Has no particular action on the
animal organism.

Contains 51'7 p. c. C., 5'8 H., 4-08 N., and 38'42 0., agreeing with
the formula C 27 NH 18 U (Pelletier). See Couerbe's observations on this
analysis (J. Pharm. 22, 25), and Pelletier's reply (Hid. 22, 31).

(It is not certain whether the following statements apply to pseudomorphine
containing sulphuric acid, or free from it.) Pseudomorphine is decomposed

by heat, even before melting. By dry distillation it yields a small
quantity of oil, a slightly acid watery distillate containing ammonia,
and leaves a tumefied combustible cinder. Nitric acid colours pseudo-
morphine bright red, like morphine, and finally converts it into oxalic
acid. Oil of vitriol turns it brown, and decomposes it. Ferric salts
colour it bright blue, the colour disappearing on adding excess of any



METAMORPIIINE. 441

acid (as with morphine). Pseudomorphine likewise dissolves abun-
dantly in a cold solution of ferric hydrochlorate, with blue colour,
changing to dirty green when heated, and on subsequent addition of
ammonia to wine-red, with separation of a slight precipitate.

Pseudomorphine containing sulphuric acid dissolves in 770 pts.
water at 14, in 12 pts. boiling water, and crystallises on cooling ;
when freed from sulphuric acid by ammonia, it becomes still less soluble.
Dilute acids, especially hydrochloric and acetic acid, facilitate the
solution to a certain extent, whereas dilute nitric and sulphuric acid
scarcely dissolve pseudomorphine.

Pseudomorphine is not perceptibly soluble in water containing
ammonia, but dissolves readily in potash- and soda-ley, separating out
again when the solution is neutralised.

In absolute alcohol and ether it is less soluble than in water;
somewhat more in alcohol of 36 B.



2. Metamorphine.

WrrrsTEm. Pharm. Viertelj. 9, 481 ; N. Br. Arch. 105, 141 ; abstr.
Zeitschr. Chem. Pharm. 4, 101.

Found in one instance in the residue of the preparation of opium-
tincture, and obtained in the form of hydrochlorate in working up
these residues for morphine by Couerbe's method. The hydrochlorate
was decomposed with a quantity of sulphate of silver equivalent to
that of the hydrochloric acid contained in it ; the solution was filtered
from the chloride of silver, and digested with carbonate of baryta ;
and the washed mixture of carbonate of baryta and metamorphine was
treated with alcohol to extract the latter.

Properties. Flat hard prisms, yyth of a line thick, united in
stellate groups. It has no taste at first, but after a while exhibits a
very faint, biting taste, not bitter. When slowly heated to 100, it
becomes dull, and at 130 assumes a grey-brown colour without
melting, but when quickly heated it melts to a colourless liquid. The
aqueous solution has no alkaline reaction ; the alcoholic solution reacts
slightly alkaline.

Decompositions. 1. Metamorphine, which has been fused by rapid
heating, blackens quickly when further heated, and gives off an
alkaline vapour. When slowly heated to 225, it turns brown, but
does not melt. 2. Oil of vitriol dissolves metamorphine with faint
transient coloration, the acid itself at the same tune acquiring a
grey-brown colour ; oil of vitriol heated with hydrochlorate of meta-
morphine dissolves it with dirty red colour. 3. Aqueous meta-
morphine colours iodic acid yellow, and slowly sets the iodine free.
4. Nitric acid of sp. gr. 1*33 colours metamorphine orange-red,
and dissolves it with yellow colour. 5. Ferric hydrochlorate does not
colour aqueous metamorphine, but imparts a greyish-blue colour to the
hydrochlorate. 6. Nitrate of silver produces a greyish-black turbidity
in aqueous metamorphine. Hydrochlorate of metamorphine and



442 APPENDIX TO MORPHINE.

carbonate of silver yield chloride of silver; but instead of meta-
morphine, a brown decomposition-product is obtained.

Combinations. Metamorphine dissolves in 6000 pts. of cold, and
70 pts. of boiling water.

It unites with acids, forming salts. It dissolves quickly in potash-
ley, more slowly in aqueous ammonia; also in aqueous carbonate of
ammonia and carbonate of potash, especially when warmed. The
same liquids dissolve the hydrochlorate.

Hydrochlorate of Metamorphine. Slender white needles having a
silky lustre ; the aqueous- solution is strongly and purely bitter.
Dissolves in 25 pts. cold, and 2 pts. boiling water ; less freely in cold
alcohol, and in 2 pts. boiling alcohol; insoluble in ether. At 100 it
gives off 11'56 p. c. water, and then contains 12'21 p. c. hydrochloric
acid [therefore a larger proportion of hydrochloric acid than (air-dried) sex-hydrated
hydrochlorate of morphine (Wittstein), but nearly as much as the morphine-salt
dried at 100, with which it is perhaps isomeric (Ludwig, Apotkek. Zeit. 1, 41)].

From hydrochlorate of metamorphine, mercuric chloride throws
down white flocks ; from terchloride of gold, reddish-yellow ; from
bichloride of platinum, light yellow flocks soluble in water. Tannic
acid produces in the solution a yellowish- white turbidity.

Metamorphine dissolves in 330 pts. of cold, and 9 pts. of boiling
alcohol of 90 per cent. It is insoluble in ether.



3. Porphyroxine.
E. MERCK. Ann. Pharm. 21, 201.

Occurs to the amount of \ per cent, in East Indian, also in Smyrna
opium, and probably also in other sorts ; not in the alcoholic extracts
of European poppy-heads. On Gibb's porphyroxine, see the appendix to
Chelerythrine.

On the relation of porphyroxine to acids, Hiiussler (N. J. Pharm. 14, 187) founds
a process for the detection of opium. See also Robertson (N. J. Pharm. 22, 190 ;
Liel. Kopp's Jahresber. 1852, 742).

Preparation. When opium is exhausted with boiling ether, the
residue heated with water and a small quantity of carbonate of
potash, and then again treated with boiling ether, the ether takes up
codeine, thebame, porphyroxine, and caoutchouc, which remain behind
when the solution is left to evaporate. The residue is dissolved in
cold, very dilute hydrochloric acid, and the solution is filtered and
precipitated by ammonia ; whereupon codeine remains dissolved,
while thebaine and porphyroxine are precipitated. On dissolving the
dried and pulverised precipitate in boiling ether, and leaving the
solution to evaporate in the air, crystals of thebaine and resinous
porphyroxine remain behind, and may be separated by alcohol, which
easily dissolves the porphyroxine.

Properties. Slender, shining needles. Neutral.

With oil of vitriol, and with nitro-sulp\uric acid, it assumes an olive-



EVERNIC ACID. 443

green colour. The colourless solution in dilute sulphuric, hydrochloric,
or nitric acid assumes, on boiling, a purple-red colour, changing to
rose-red on dilution ; the solution in acetic acid remains colourless,
even at the boiling heat. Alkalis decolorise the liquids, and produce a
white precipitate ; and on subsequently adding any acid, even acetic
acid, to the solution, the red colour is restored without the application
of heat. The purple-red solution in hydrochloric acid is precipitated
by protochloride of tin and by tannic acid ; neutral acetate of lead
renders it rose-red ; chloride of gold, dirty red ; it is not precipitated
by sulphate of copper. Ferrous hydrochlorate colours the solution
brown.

Insoluble in water (Riegel).

Porphyroxine is precipitated by alkalis from its colourless solution
in dilute acids, as a loose bulky mass, which cakes together when



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