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these bases exist associated with other bases, one or two of which will be noticed in conjunction with them. They are bodies of great medicinal importance; and as toxicological cases frequently arise in which these substances are concerned, the student ought to be fully acquainted with their reactions. Being all entirely constituted of the four elements carbon, hydrogen, nitrogen, and oxygen, they are all volatile, or decompose, leaving a residue of carbon, upon the application of heat, and may thus be readily distinguished from every other member of the group with which, by the action of reagents, they may occasionally be confounded. Another peculiarity which they present, is the ready solubility of their salts in alcohol. These compound bases combine directly with acids to form salts without the disengagement of hydrogen, as is the case with certain elementary basic radicals which have been described. On this account, these substances can scarcely be considered as basic radicals; for the sake of convenience we will term them basic bodies.

SALTS OF MORPHINE. Solution for the reactions :-hydrochlorate of morphine (C1, H2, NO, CI +3aq) in water.

The very complex basic body morphine, combines with acids to form perfectly stable salts : all these salts are, however, formed after one typethat of a proto-salt; and their general formula is consequently MR.

Morphine, like quinine and strychnine, may be regarded as an ammonia, and like ordinary ammonia (NH3), when combining with acids, becomes a salt of ammonium (NH): thus

NH,+HCI=NH,CI; C, H, NO,+HCI = C, H, NO,CI ammonia. hydrochlorate of morphine. hydrochlorate of morphine, ammonia, or chloride

or chloride of morphineof ammonium.

ammonium. Salts of morphine are generally very soluble in water and alcohol, but insoluble in ether. They are without colour, unless their acid-radical introduces it ; their taste is bitter, and they are poisonous. When heated they carbonize, i.e. suffer complicated decomposition, one of the results of which is the separation of carbon; this residual carbon will burn entirely away if free access of air be allowed, the heat being still maintained. With other agents also, as sulphuric acid, peroxide of lead, &c., characteristic products of decomposition are obtained, by means of which morphine may be recognized :

a. When powdered morphine, or a concentrated solution of a morphine salt, is projected into a concentrated solution of ferric sulphate, which must be neutral, or but slightly acid, the latter is coloured of a deep blue. This colour disappears by the addition of acid or alcohol, or upon the application of heat.

B. The addition of nitric acid to a salt of morphine, or its concentrated solution, gives a reddish orange-colour, which passes into a yellow.

Among insoluble morphine salts are the following:--the chloroplatinate, the carbazotate, the hydrate, the ferrocyanide, the ferricyanide, and the phosphate.

Morphine is always associated with another base, narcotine (among others), which may be thus distinguished :—its hydrate is insoluble in hydrate of potassium, but soluble in ether, while concentrated nitric acid dissolves narcotine without coloration, becoming yellow, however, on heating.

THE CHROMATE AND CYANIDE are unknown.

THE CHLOROPLATINATE is produced by the addition of chloroplatinic acid to a solution of a salt of morphine. It is a yellow, curdy precipitate.

Its composition is C, H, NO, PtCl.
It is somewhat soluble in water, and may be crystallize.l.
THE CARBAZOTATE is unknown.

The Hydrate is produced by the action of a very dilute solution of hydrate of potassium (not in excess) upon solutions of morphine ; it is also produced by the carbonates and acid carbonates of the alkalies. It is a white precipitate.

Its composition is C, H20NO,HO.

It is easily soluble in the hydrates of potassium and calcium (lime-water), in the hydrate and chloride of ammonium, but is scarcely soluble in cold water; boiling water dissolves about toth of its weight of the hydrate. In cold alcohol it is but slightly soluble, but it dissolves more readily at the boiling temperature. It is insoluble in ether. Most acids dissolve it.

THE SULPHYDRATE is unknown.
THE SULPHATE is very soluble.

The CARBONATE is produced only when a solution of carbonic acid gas, made under pressure and saturated with morphine, is considerably cooled without the pressure being removed.

THE OXALATE is hardly known.
THE FERROCYANIDE is not well known; but it appears to be soluble.

THE FERRICYANIDE is produced by the action of ferricyanide of potassium upon solutions of morphine salts. It is a yellow crystalline precipitate.

THE PHOSPHATE is produced by phosphate of sodium as a crystalline precipitate very soluble in water.

The action of many of the special reagents of the present and two preceding groups upon morphine salts has not been ascertained.

Morphine is generally recognized by the reactions with ferric sulphate and nitric acid.

SALTS OF QUININE. Solution for the reactions :—sulphate of quinine ([C2H,,0,,50x+7aq) in dilute sulphuric acid.

The compound basic body quinine unites with most acids to form salts of great stability. They are all formed upon the type MR, the chloride, or

rather the hydrochlorate, having the formula C20H, N.,0,C1, which is equivalent to QuHCI, Qu being the symbol for 1 equivalent of the basic body, or ammonia-quinine (C2H,,N,0).

Salts of quinine are not usually very soluble in water. Some of their acid solutions exhibit the very remarkable phænomenon of Auorescence or epipolic dispersion,-a magnificent blue luminosity seen upon the surface of the liquid when viewed in reflected light, and which is owing to a change effected in the actinic rays by the dissolved quinine salt. The hydrochlorate of quinine does not exhibit this curious property. Quinine salts are, for the most part, extremely soluble in alcohol, while some dissolve also in ether: generally they are without colour, and very bitter in taste. When heated, they generally leave a residue of carbon, unless with an acid-radical (as in the chlorate) containing much oxygen : such salts, indeed, usually explode. Peculiar products of decomposition may be obtained by the action of many reagents; and by these and other methods this body may be recognized.

Among these reactions are the following:

a. If to a solution of a quinine salt, freshly prepared chlorine water be added, and then a few drops of hydrate of ammonium, a green colour is obtained ; and if too much of the hydrate has not been added, the addition of a few drops more of chlorine water will convert the green tinge into a violet, and finally into a deep red.

B. Concentrated nitric acid dissolves quinine and many salts of quinine, forming a colourless solution, which becomes only faintly yellow on heating.

Among the insoluble salts of quinine are the hydrate and the sulphate.

Quinine is invariably associated to a large extent with cinchonine, which may be distinguished from quinine by the insolubility of its hydrate in dry ether. Addition of chlorine water causes no coloration in a solution of a cinchonine salt, while the subsequent addition of ammonia produces a yellowish-white precipitate.

THE CHROMATE AND CYANIDE are unknown.

THE CHLOROPLATINATE is produced by the action of chloroplatinic acid : it is a pale yellow flocculent precipitate, which becomes orange and crystalline by agitation.

Its formula is said to be C2H25 N, 0,,H(PtCl,)2 +aq.
THE PERCHLORATE is soluble, and the CARBAZOTATE is unknown.

The Hydrate is produced by the action of the hydrates and carbonates of potassium or ammonium, and by the sulphydrate of ammonium: it is a white curdy precipitate.

Its formula is C20 H25 N, 02, H, 0+2aq.

It is but slightly soluble in hydrate or carbonate of potassium, but dissolves more readily in hydrate of ammonium; it dissolves in 350 parts of cold, and in 400 parts of boiling water; it is extremely soluble in alcohol, and somewhat so in ether. It is dissolved by most acids.

THE SULPHYDRATE is not known.
THE SULPHATE is the commonest salt of quinine : it is comparatively in-

H

soluble in cold water, requiring 265 parts of water at 15° C., and 24 parts of boiling water, for solution ; it is extremely soluble in alcohol, and somewhat so in ether; it is dissolved by most acids.

THE CARBONATE is only obtained by allowing a carbonic acid solution of hydrate of quinine to evaporate spontaneously. · THE OXALATE is obtained by adding oxalate of ammonium to a solution of the acetate of quinine : it is a white precipitate, and is but slightly soluble in cold water or alcohol, but soluble in boiling alcohol.

THE FERROCYANIDE is produced when alcoholic solutions of hydroferrocyanic acid (H, Cfy) and of quinine are mixed, and separates as an orange crystalline precipitate.

Its composition is C20 H25 N, 02, H2, Cfy, +2aq.

THE FERRICYANIDE is produced by the action of a concentrated solution of ferricyanide of potassium on a solution of hydrochlorate of quinine containing some free hydrochloric acid, and is precipitated as a golden-yellow crystalline powder.

It is easily soluble in water.

THE PHOSPHATE is a white crystalline body, very soluble in hot phosphoric acid.

SALTS OF STRYCIININE. Solution for the reactions :-hydrochlorate of strychnine (C21H, N, O,,CI) in water.

The compound basic body strychnine combines with most acids to form very stable salts, which are formed upon the type MR.

Most salts of strychnine are soluble in water; they are colourless unless their acid-radical introduces colour; they are intensely bitter and exceedingly poisonous : when heated they usually carbonize, and yield with some reagents characteristic products.

Strychnine may be recognized-

a. By dissolving the base of its salt in a drop of concentrated sulphuric acid, and adding to the solution one drop of a solution of chromate of potassium, when a purplish-blue colour is produced, which changes to red. The presence of sugar and of quinine is said to interfere with this test, but not when applied as follows :—the sulphuric acid solution of strychnine, to which a few drops of nitric acid has been added, is mixed with a few grains of peroxide of -lead (Pb, 02), when the liquid becomes successively blue, violet, and greenish-yellow*.

B. Concentrated nitric acid dissolves strychnine, forming a solution colourless in the cold, but which becomes slightly yellow on heating. If to this solution a small quantity of peroxide of lead be added, the same changes of colour may be witnessed as in the preceding experiment.

* These and similar experiments, where a transparent colouration is produced, should be performed upon a fragment of white porcelain.

Among the insoluble salts of strychnine are these,--the chromate, the chloroplatinate, and the hydrate.

Strychnine is associated in nature, to a certain extent, with another base, brucine, which may be readily distinguished from it by being soluble in absolute alcohol. The action, too, of nitric acid upon the two bodies differs : it dissolves brucine, and colours the solution intensely red; when heated, this colour changes to yellow; and if stannous chloride or sulphide of ammonium be then added, the colour again changes and becomes a most intense violet.

THE CHROMATE is produced by the action of chromate of potassium : it is a brownish-yellow precipitate, slightly soluble in cold water or alcohol, but much more soluble in boiling water.

THE CYANIDE does not exist.

THE CHLOROPLATINATE is produced by the action of chloroplatinic acid on hydrochlorate of strychnine.

Its composition is C, H, N, 02, PtClz.

It is almost insoluble in water and in weak and boiling alcohol, also in ether.

THE PERCHLORATE is comparatively insoluble in water, but far more soluble in alcohol.

THE CARBAZOTATE is unknown.

The Hydrate is produced by the action of the hydrate or carbonate of potassium, and of the hydrate of ammonium on solutions of strychnine salts (not too dilute): it is a white precipitate, which appears crystalline under the microscope.

Its composition probably is C, H, N, 0,,HO.

It is insoluble in hydrate or carbonate of potassium, but soluble in hydrate of ammonium. It is almost insoluble in water, 1 part requiring 6667 parts of water at 10° C. for solution, and 2500 parts of boiling water; nevertheless its cold aqueous solution, when diluted with 100 times its volume of water, possesses a marked degree of bitterness. It is very soluble in alcohol, but insoluble in absolute alcohol or ether. It dissolves in most acids.

THE SULPHYDRATE is unknown.

THE CARBONATE is said to be produced when a strychnine salt is precipitated by an alkaline carbonate.

The OXALATE and THE SULPHATE are soluble.

THE FERROCYANIDE is produced by mixing saturated solutions of ferrocyanide of potassium and of a strychnine salt, and is a precipitate composed of nearly colourless needles.

Its composition is (C2H, N, 02), Cfy+4aq.

It is but slightly soluble in cold water or alcohol, but far more soluble in these liquids at the boiling temperature.

THE FERRICYANIDE appears to be soluble.
THE PHOSPHATE is soluble; THE SILICOFLUORIDE does not exist, being re-

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