It can also be determined as sulphide, by precipitation with sulphuretted hydrogen, the precipitated sulphide being dried at Ioo° C. and weighed.
The British Pharmacopoeia contains (i) an extract of the fresh corm, having doses of 4 to i grain, and (2) the Vinum Colchici, made by treating the dried corm with sherry and given in doses of 10 to 30 minims. This latter is the preparation still most generally used, though the presence of veratrine both in the corm and the seeds renders the use of colchicine itself theoretically preferable.
Among the rest was a dried tapeworm.
The precipitate is washed, collected, and dried at a very moderate heat.