ether, the latter requiring at 17° C. (62.6° F.) 370 parts of ether for solution.

In the absence of any specially characteristic chemical test for cinchonidine, its identity as a cinchona alkaloid may be determined, in connection with the described physical characters, by its property of affording, when mixed with a little sugar, and heated in a perfectly dry test-tube, a bright-red tarry sublimate, which, as far as at present known, is only produced by the dry distillation of cinchona barks or their alkaloids, when in contact with some indifferent organic substance, such as sugar.

When cinchonidine is dissolved in water, acidulated with dilute sulphuric acid, it responds to the tests for a solution of cinchonidine sulphate, as described under the latter, on page 314.

CINCHONIDINÆ SULPHAS.

CINCHONIDINUM SULFURICUM.

Sulphate of Cinchonidine or Cinchonidia.

Cinchonidine Sulphate.

Ger. Schwefelsaures Cinchonidin; Fr. Sulfate de cinchonidine; Sp. Sulfato de cinconidina.

(C1,H2N2O),. H ̧SO, + 3H ̧0; 740.

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4

Colorless, silky, lustrous needles, or thin quadrangular prisms, without odor, but possessing a very bitter taste, and feebly alkaline reaction. They contain about three molecules (7.30 per cent.) of water of crystallization when crystallized from a concentrated aqueous solution, or six molecules (13.60 per cent.) when crystallized from a dilute aqueous solution. When heated to 100° C. (212° F.) the salt loses its water of crystallization, and when strongly heated upon platinum-foil it is decomposed and charred, and finally completely dissipated.

Cinchonidine sulphate is soluble in 100 parts of water and in 71 parts of alcohol at 15° C. (59° F.), in 4 parts of boiling water and in 12 parts of boiling alcohol, freely soluble in acidulated water, and soluble in 1000 parts of chloroform; but nearly insoluble in ether and benzol. The aqueous solution possesses a bitter taste, and is precipitated by the general alkaloidal reagents: potassio-mercuric iodide, platinic chloride, tannic acid, etc., and upon the addition of solutions of the alkaline hydrates, carbonates, or bicarbonates, a white precipitate of cinchonidine is produced, which is nearly insoluble in an excess of the precipitant, but soluble in about 76 times its weight of ether, and, upon standing, becomes crystalline; with solution of barium chloride it yields a white precipitate of barium sulphate, insoluble in hydrochloric acid.

In contact with concentrated nitric or sulphuric acid, cinchoni

dine sulphate suffers no change of color (distinction from brucine, morphine, salicin, etc.), and its solution in the latter acid does not afford a purple coloration in contact with a crystal of potassium bichromate (distinction from strychnine).

The solution of cinchonidine sulphate in water, acidulated with sulphuric acid, displays no fluorescence, and, upon the addition of a little chlorine-water, and subsequently of ammonia, no green coloration is produced (distinction from the sulphates of quinine and quinidine). It is distinguished from cinchonine sulphate by the solubility of the latter in 60 parts of chloroform, whereas cinchonidine sulphate, as previously stated, requires 1000 parts of

chloroform for solution.

A cold saturated solution of cinchonidine sulphate affords, upon the addition of a solution of potassium and sodium tartrate (Rochelle salt), in slight excess, a white crystalline precipitate of cinchonidine tartrate, (C,,H,N,O),.CHO + 2H2O, which requires 1265 parts of water for solution, and is quite insoluble in an excess of the reagent.

Examination :

Moisture, or the verification of the proper amount of water of crystallization, may be determined by exposing one gram of the salt to the temperature of 100° C. (212° F.), until the weight remains constant; when thus dried the residue should weigh not. less than 0.92 gram, indicating an amount of water corresponding to between three and four molecules.

Cinchonine and Quinidine Sulphates.—In addition to the above described points of distinction, the presence of any appreciable amount of cinchonine or quinidine sulphates may be readily detected by the following test: 0.5 gram of the cinchonidine sulphate is digested with 20 cubic centimeters of cold distilled water, 0.5 gram of potassium sodium tartrate added, the mixture macerated, with frequent agitation, for one hour, at 15° C. (59° F.), then filtered, and one drop of ammonia-water added to the filtrate, when not more than a slight turbidity should occur; a white precipitate would indicate the presence of more than 0.5 per cent. of cinchonine sulphate, or of more than 1.5 per cent. of quinidine sulphate.

Colorless, transparent, monoclinic prisms or needles, without odor, and at first nearly tasteless, but developing a bitter after

taste, and possessing an alkaline reaction. They contain no water of crystallization, and are permanent in the air. When heated to 220° C. (428° F.) they begin to volatilize, and when heated in a current of hydrogen or ammonia gas, they may be sublimed, without decomposition, in long needles; they melt at about 250° C. (482° F.), but assume a brown color, and become thereby par tially decomposed; when more strongly heated, upon platinum. foil, they become charred, and are finally completely dissipated.

Cinchonine is very sparingly soluble in cold water, one part requiring at 17° C. (62.6° F.) 3700 parts for solution, and is not much more soluble in solutions of the alkalies or in boiling water, requiring of the latter about 2500 parts for solution; it is soluble in 110 parts of alcohol at 15° C. (59° F.), in 28 parts of boiling alcohol, in 370 parts of ether, and in 350 parts of chloroform. It dissolves readily in dilute mineral acids, with the formation of neutral or acid salts, which are mostly well crystallizable, and possess a persistent, strongly bitter taste.

In contact with concentrated nitric or sulphuric acid, cinchonine suffers no change of color (distinction from brucine, morphine, salicin, etc.), and its solution in the latter acid does not afford a purple coloration in contact with a crystal of potassium bichromate (distinction from strychnine).

The aqueous solution of cinchonine possesses an alkaline reaction and a bitter taste. When cinchonine is dissolved in water, acidulated with dilute sulphuric acid, the solution displays no fluorescence, and, upon the addition of a little chlorine-water, and subsequently of ammonia, no green coloration is produced (distinction from quinine and quinidine). It is distinguished from cinchonidine by the solubility of the latter in 76 parts of ether, whereas cinchonine, as stated above, requires 370 parts for solution.

In the absence of any specially characteristic chemical test for cinchonine, its identity may be determined, in connection with the above described physical characters, by its property, common to all cinchona alkaloids, of affording, when mixed with a little sugar, and heated in a perfectly dry test-tube, a bright-red tarry sublimate, which, as far as at present known, is only produced by the dry distillation of cinchona barks, or the alkaloids contained therein, when in contact with some indifferent organic substance, such as the above-mentioned carbohydrate.

When cinchonine is dissolved in water, acidulated with dilute sulphuric acid, it responds to the tests for a solution of cinchonine sulphate, as described under the latter, on page 317.

CINCHONINÆ SULPHAS.

CINCHONINUM SEU CINCHONIUM SULFURICUM.

Sulphate of Cinchonine or Cinchonia. Cinchonine Sulphate. Ger. Schwefelsaures Cinchonin; Fr. Sulfate de cinchonine; Sp. Sulfato de cinconina.

(C1H2N2O),.H2SO ̧+2H2O; 722.

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Transparent and colorless, hard, shining prisms of the monoclinic system, possessing no odor, but a very bitter taste, and a slightly alkaline reaction. They contain two molecules (498 per cent.) of water of crystallization, which are lost by drying at 100° C. (212° F.). When heated to about 240° C. (464° F.), the salt melts with partial sublimation, and when strongly heated, upon platinum foil, it fuses to a red, resinoid mass, becomes charred, and is finally completely dissipated.

Cinchonine sulphate is soluble in about 70 parts of water and in 6 parts of alcohol at 15° C. (59° F.), in 14 parts of boiling water, in 1.5 parts of boiling alcohol, and in about 60 parts of chloroform, but is insoluble in ether or benzol; it dissolves readily in dilute sulphuric acid, with the formation of an acid sulphate, or mono-cinchonine sulphate, C,H,N2O.H2SO, +4H2O, which is difficultly crystallizable, and soluble in half its weight of water, but requires 100 parts of absolute alcohol for solution.

222

The aqueous solution of cinchonine sulphate possesses a very bitter taste, and exhibits no fluorescence; it is precipitated by the general alkaloidal reagents: potassio-mercuric iodide, platinic chloride, tannic acid, etc., and upon the addition of solutions of the alkaline hydrates, carbonates, or bicarbonates, a white precipitate of cinchonine is produced, which is but very sparingly soluble in an excess of the precipitant; with potassium ferrocyanide a white amorphous precipitate is produced, which, upon warming, is soluble in an excess of the reagent, and is separated in a crystalline form upon cooling; with solution of barium chloride it yields a white precipitate of barium sulphate, insoluble in hydrochloric acid.

In contact with concentrated nitric or sulphuric acid, cinchonine sulphate suffers no change of color (distinction from brucine, morphine, salicin, etc.), and its solution in the latter acid does not afford a purple coloration in contact with a crystal of potassium bichromate (distinction from strychnine).

Cinchonine sulphate is distinguished from the sulphates of quinine and quinidine, by its greater solubility in water, by the absence of any fluorescence of its solution in dilute sulphuric acid, and by the latter solution, upon the addition of a little. chlorine-water and subsequently of ammonia, affording no green coloration; it is also distinguished therefrom by the very sparing

solubility of the pure alkaloid, when precipitated from a solution of its salt by ammonia-water, and subsequently shaken with ether. It is distinguished from cinchonidine sulphate by the latter requir ing 1000 parts of chloroform for solution, whereas anhydrous cinchonine sulphate is soluble in 60 parts of chloroform; and, on the other hand, free cinchonidine is soluble in 76 parts of ether, whereas pure cinchonine requires 370 parts of ether for solution.

Colorless, transparent, octahedral crystals, belonging to the rhombic system, and containing one molecule (5.68 per cent.) of water of crystallization, which is lost by drying at 120° C. (248° F.). When crystallized from anhydrous ether or carbon bisulphide, it forms small, colorless crystals, containing no water of crystalliza tion, but likewise belonging to the rhombic system.

Codeine, when previously deprived of its water of crystallization, melts at 150° C. (302° F.), and solidifies upon cooling in a crystalline form; when strongly heated upon platinum foil, it is decomposed with the evolution of inflammable vapors, and is finally completely dissipated. It is soluble in 80 parts of water at 15° C. (59° F.), and in 17 parts of boiling water, in 6 parts of ether, in 10 parts of benzol, and freely soluble in alcohol, amylic alcohol, chloroform, and carbon bisulphide, but very sparingly soluble in petroleum benzin; when heated with less water than is required for solution, or when dropped into boiling water, it sinks to the bottom, and melts in the form of an oily liquid. It is also readily soluble in dilute acids, with the formation of well crystallizable salts, which are soluble in water and alcohol, but nearly insoluble in ether, and possess a strongly bitter taste.

The aqueous solution of codeine has a very bitter taste and strongly alkaline reaction, precipitating from neutral solutions of the salts of lead, iron, copper, cobalt, and nickel, their respective hydrates; and is itself precipitated by the ordinary alkaloidal reagents: potassio-mercuric iodide, iodinized potassium iodide, tannic acid, platinic chloride, etc., as also from its saturated solution by concentrated solutions of potassium or sodium hydrate, but remains unchanged upon the addition of ammonia-water, in which liquid it is nearly as soluble as in pure water.

When a cold saturated aqueous solution of codeine is care