ON COLCHICIA. 
251 
solution of copper. Colchiceine is sparingly soluble in cold, more in hot water; the 
aqueous solution is coloured yellow by dilute acids, violet and brown by concentrated 
nitric acid, precipitated by tannin, chloride of platinum, chloride of gold, nitro-picric 
acid, solution of iodine, and chlorine water, not by corrosive sublimate ; the reactions 
are, therefore, almost identical with those of the amorphous colchicia; the alkaline na¬ 
ture of this body is denied ; it was almost without action upon slightly reddened litmus- 
paper. 
M. Htibler (Jenaische Zeitsch. f. Med. u. Naturw., 1861, 217) prepared colchicia by a 
process similar to Ludwig’s, except that the aqueous solution of the alcoholic extract 
was precipitated by subacetate of lead, and the lead removed by phosphate of soda; 
colchicia was precipitated by tannin in fractions, the middle portion was decomposed by 
oxide of lead, and the fractional precipitation by tannin and decomposition, by oxide of 
lead repeated until the product was of a sulphur-yellow colour and soluble in alcohol 
and water without turbidity. It is amorphous, of a faint aromatic odour, and intensely 
bitter taste, fusible at 140° C. (281° F.), insoluble in ether, readily soluble in water and 
alcohol, without action on litmus-paper, and produces in aqueous solution a yellow 
colour with mineral acids and alkalies, and precipitates with chloride of gold (yellow), 
corrosive sublimate (white), and tannin (curdy); not with chloride of platinum, per- 
chlorideof iron, subacetate of lead, and sulphate of copper; its composition is C 34 H ]9 NO J0 . 
Heated with dilute sulphuric acid, a resinous body and colchiceine is obtained, which is 
removed from its aqueous solution by animal charcoal, and converted into a brown un- 
crystallizable body, which is also formed from the solution in contact with air. It has 
the same composition as colchicia, has an acid reaction, decomposes the carbonates, is 
soluble in alkalies, and these solutions are precipitated by salts of the alkaline earths 
and metallic oxides ; it appears also to be formed by the action of alkalies upon colchicia, 
and does not pre-exist in the seeds of colchicum. Pure colchicia in doses of '05 grm. 
killed dogs, but did not affect rabbits in doses of *1 grm. 
The collection of chemicals in the Philadelphia College of Pharmacy contains a spe¬ 
cimen of colchicia prepared by Mr. Carter in 1857; a portion of this was used for the 
purpose of clearing up the contradictions in the statements of the above authors. The 
substance is a light yellow, amorphous powder, possessing a very faint odour and in¬ 
tensely bitter taste, sparingly soluble in ether, but easily soluble in water and alcohol, 
the aqueous solution being slightly turbid, most likely in consequence of the decompo¬ 
sition of a small portion into resin and colchiceine. Heated upon platinum foil, it 
fuses ; at a higher heat it takes fire and burns without leaving any residue. Placed 
upon moistened red litmus-paper, the blue colour is restored; very faintly reddened 
litmus becomes blue also by a concentrated aqueous solution. One drop of dilute sul¬ 
phuric acid dropped from a bottle giving fifty-two drops to the fluid drachm, conse¬ 
quently about | grain of HO, S0 3 , when mixed with 1 grain of colchicia, retained its 
acid reaction. One drop of the acid was mixed with 1 fluid ounce of distilled water ; in 
5 minims of this mixture, equal to about 7 )- u grain of HO, S0 3 , T x ¥ of grain of colchicia 
was dissolved, and the solution now r had a distinct alkaline reaction on slightly reddened 
litmus-paper ; but on heating this solution to the boiling-point, it had acquired an acid 
reaction. It will be seen that two important statements of Mr. Carter are corroborated, 
namely, the alkaline reaction of colchicia and its power to destroy the acid reaction of 
sulphuric acid. 
The behaviour of colchicia towards reagents I found to be as described by the au¬ 
thors quoted above ; the most important tests for recognizing the presence of colchicia, 
are its behaviour to dilute acids and also alkalies, by which its solution acquires a yellow 
colour, and the violet and blue colour which is produced by oxidizing agents with dry 
colchicia. This latter colouration, which changes through various shades finally into 
yellow, is strikingly beautiful when concentrated sulphuric acid is used, and immediately 
some nitric acid or a fragment of a nitrate is added ; strong nitric acid produces it like¬ 
wise, but it changes more rapidly to yellow. Sulphuric acid, with a trace of chromate 
or bichromate of potassa, or of sesquichloride of iron, or of binoxide of lead, shows 
the same reaction at the point of contact with colchicia; the liquid itself has a green 
colour with the first two reagents, owing to their intense yellow colour. 
One grain of colchicia was dissolved in 1 fluid ounce of distilled water, slightly acidu¬ 
lated with muriatic acid ; by repeated trials it required 114 drops from this vial to make 
1 fluid drachm; this measure had been carefully gauged with a pipette graduated into 
