BELLADONNA. 
450 .] 
with two successive portions, each of 10 millilitres, of the diluted acid. 
Make the mixed acid solutions alkaline with solution of ammonia, and 
shake out with three successive portions of 15, 15, and 5 millilitres of 
chloroform. Evaporate the mixed chloroformic solutions to dryness, 
dissolve the residue in 3 millilitres of ether, and again evaporate to 
dryness. Dissolve the residue in 10 millilitres of N/20 solution of 
sulphuric acid, and titrate with N/20 solution of sodium hydroxide, 
tincture of cochineal being used as indicator. Deduct the number of 
millilitres of the alkaline solution required from 10, multiply the differ¬ 
ence by 0-1446 ; the product will be the percentage of alkaloids in the 
leaves. 
Dry Extract of Belladonna .—This is made by percolating by means of 
alcohol belladonna leaves, determining the alkaloids therein, and adding 
sufficient powdered leaves to make, when dried, a dry extract of a strength 
of 1 per cent, by weight of alkaloids. 
Tincture of Belladonna .—A tincture of the leaves, made by percolating 
100 grms. of dried belladonna leaves in No. 20 powder with 1000 millilitres 
of alcohol (70 per cent.). The tincture is assayed as follows :—Evaporate 
100 millilitres in an evaporating basin on a water-bath until it measures 
about 10 millilitres ; add, if necessary, sufficient alcohol (90 per cent.) to 
dissolve any separated substance, and transfer to a separator, rinsing the 
dish with a little water. Add 10 millilitres of water, 20 millilitres of 
chloroform, and 2 millilitres of solution of ammonia. Shake well, and 
separate the chloroformic layers. Repeat the extraction with two 
successive portions of 10 millilitres of chloroform. Mix the chloroformic 
solutions and shake them with 10 millilitres of N/1 solution of sulphuric 
acid diluted with twice its volume of water. Separate the chloroformic 
solution. Repeat the shaking with a further 10 millilitres of the acidified 
water. Mix the acid solutions, add 20 millilitres of chloroform and 
4 millilitres of solution of ammonia. Shake well, draw off the chloro¬ 
formic solution into a beaker, and repeat the extraction with two further 
portions, each of 10 millilitres, of chloroform. Allow the mixed chloro¬ 
formic solutions to evaporate, dry the residue on a water-bath for 
thirty minutes, dissolve it in 10 millilitres of N/20 solution of sulphuric 
acid, and titrate with N/20 solution of sodium hydroxide, using tincture 
of cochineal as indicator. Deduct the number of millilitres of alkaline 
solution required from 10, and multiply the difference by 0-01446 ; the 
product will be the weight in grammes of the alkaloids contained in 
100 millilitres of the tincture. This quantity should be not less than 
0-035 grm. Should the tincture contain more than this proportion, it 
must be diluted with the necessary quantity of alcohol (70 per cent.). 
Hence the strength of the tincture should be 0-035 grm. of alkaloids in 
100 millilitres. Limit of plus or minus error, 2 milligrms. 
(b) Belladonna Root .—Liquid extract of belladonna (root) is prepared 
25 
