UNIFICATION OF PHARMACOPOEIAS
I4()
Identification. — Dissolve 1 mg. in 5 ml. of water; add slowly
to 1 ml. of the solution 2 ml. of a 0.125 per cent w/v solution of
p-dimethylaminobenzaldeliyde in a cooled mixture of 65 ml. of sul¬
phuric acid and 35 ml. of water, containing 0.1 ml. of a 5 per cent w/v
solution of ferric chloride in water, and mix ; a deep-blue colour is
produced.
Melting-point. — Melting-point of the lower-melting form, deter¬
mined on the air-dried substance, the rate of rise of temperature
being 1° per minute, 162° to 164°, with decomposition ; melting-
point of the higher-melting form, determined on material which has
been dried at 140° in vacuo for one hour, 212° with decomposition.
Reaction. — An aqueous solution has an alkaline reaction to
litmus.
Specific Rotation. — The specific rotation in a 1.5 per cent w/v
solution in dehydrated alcohol, determined on the air-dried sub¬
stance and calculated with reference to the substance from which the
associated solvent has been removed (sodium light), +40° to +43° ;
(mercury light), +60° to +63°. The proportion of associated solvent
is determined by heating at 140° in vacuo for one hour.
Other Ergot Alkaloids. — Dissolve 2 mg. in 2 ml. of water ; add
2 drops of hydrochloric acid ; the liquid remains clear.
Storage. — Ergometrine must be kept in an atmosphere of
nitrogen in sealed tubes, protected from light.
ERGOTOXINI AETHANOSULFONAS
C35H4106N5,C2H5S03H. Mol. Wt. 737.8.
Description. — White crystalline odourless powder, unstable in
contact with air and light.
Solubility. — Sparingly soluble in water, soluble in alcohol (90 per
cent), very soluble in methyl alcohol.
Identification.— (a) The saturated aqueous solution exhibits
a blue fluorescence ; it is acid to litmus.
(b) Dissolve 1 mg. in 5 ml. of water; to 1 ml. of this solution
add slowly 2 ml. of a 0.125 per cent w/v solution of p-dimethylamino-