§ 396-1 STRYCHNINE. 329 
ladium compound (C 21 H 22 N 2 0 2 ,HClPdCl) is in dark brown needles, and 
the gold compound (C 21 H 22 N 2 0 2 ,HC1 AuC 1 3 ) in orange-coloured needles. 
4. Strychnine Trichloride.— The action of chlorine on strychnine— 
by which chlorine is substituted for a portion of the hydrogen—has been 
proposed as a test. The alkaloid is dissolved in very dilute HC1, so as 
to be only just acid ; on now passing through chlorine gas, a white preci¬ 
pitate is formed, which may be recrystallised from ether ; it has probably 
the composition C 21 H 19 C1 3 N 2 0 2 , and is extremely insoluble in water. 
5. The Iodide of Strychnine (C 21 H 22 N 2 0 2 ,HI 3 ) is obtained by the 
action of iodine solution on strychnine sulphate ; on solution of the 
precipitate in alcohol, and evaporation, it forms violet-coloured crystals, 
very similar to those of potassic permanganate. 
§ 396. Pharmaceutical and other Preparations of Nux Vomica and 
Strychnine. 
Liquid Extract of Nux Vomica. —The liquid extract of nux vomica 
of the B.P. is made as follows :— 
Nux vomica, in No. 20 powder, 1000 grms.; alcohol, 70 per cent., a 
sufficient quantity. The nux vomica is exhausted with the alcohol 
by the percolation process, until 500 c.c. have been obtained. This 
percolate is heated with solid paraffin wax, 15 grms., in a closed vessel 
at 60° for a few minutes, and shaken vigorously. The contents of the 
vessel and the paraffin are cooled ; the percolate, free from fat, is separated 
from the paraffin wax. 10 c.c. of the percolate are evaporated down to a 
syrup. To this 10 c.c. of water are added and transferred to a separator, 
the dish being washed by a further 10 c.c. of water. 10 c.c. of chloroform 
are added, and 25 c.c. of a 20 per cent, solution of sodium carbonate. The 
mixture is shaken vigorously, and, after standing, the chloroform layer 
separated. The same quantity of chloroform, shaking and separating, 
is repeated twice more, that is to say, in all 30 c.c. are used. The united 
chloroform solutions are shaken with three successive portions, 10 c.c. 
each, of d.n. sulphuric acid. The united acid solutions are placed in a 
second separating funnel. To this solution ammonia is added to alkaline 
solution, and the alkaloidal content shaken out, successively, with 10, 
5, and 5 c.c. of chloroform, the chloroform extracts being run into a small 
flask. The chloroform in this flask is now distilled off, and the residue 
dissolved in 15 c.c. of 3 per cent, sulphuric acid ; the solution is heated to 
50°, and to the warm solution is added 3 c.c. of a mixture of equal volumes 
of nitric acid and water, and set aside for ten minutes. The solution is 
transferred to a separator, the flask being rinsed with a little water 
made alkaline by sodium hydroxide, and extracted again with 10, 5, 
and 5 c.c. of chloroform. The mixed chloroformic extracts are 
washed with 5 c.c. of water, transferred to a tared dish, and the 
chloroform allowed to evaporate, adding towards the end 5 c.c. of 90 
per cent, alcohol. Finally the residue is evaporated to dryness at 100° 
