1014 DR THOMAS R. FRASER ON STROPHANTHUS HISPIDUS. 



acid was added so as to make the solution a 0'3 per cent, one of acid, and the solution 

 was then left to itself at the ordinary temperature. On the following day, it had 

 become slightly turbid, and two days afterwards several colourless rosettes of lancet- 

 shaped crystals had formed at the bottom of the flask. On the fourth day, the rosettes 

 had increased in size, and now also a general crystalline incrustation had occurred over 

 the bottom and sides of the flask, while the solution had lost its turbidity, and had 

 again become quite clear. The crystals increased in quantity during the next twenty- 

 four hours ; and, on the sixth day, when they were collected as carefully as possible, 

 they weighed 33*7 per cent, of the strophanthin used. The filtered solution, after 

 having been neutralised, was found to contain 22 per cent, of glucose. (Table XI. 

 Analysis No. 34.) 



In an experiment with the same quantity of strophanthin and of sulphuric acid in 

 solution as in the last experiment, as soon as the solution had been made it was placed 

 in the water- bath and gradually heated. While the temperature rose from 150° to 

 165° F., a beautiful crystallisation appeared in the solution, consisting of slender colour- 

 less crystals, many of them being three-fourths of an inch in length, and the solution 

 at the same time became slightly turbid. The temperature was raised to 212°, and 

 maintained at this point for half an hour ; during the boiling, an odour like that of cooked 

 raisins was given off, and the solution became slightly yellow in colour. When the 

 solution had cooled, it was found that, in addition to now partially broken, long and 

 slender crystals, a further crystallisation had formed, consisting of colourless nodules 

 or tufts attached to the bottom of the flask. The washed and dried crystals weighed 

 36 '2 per cent, of the strophanthin used, and there was found in the filtered solution 

 27*5 per cent, of glucose. (Table XL Analysis No. 35.) 



On gradually heating a solution of strophanthin which contained 0'5 per cent, 

 sulphuric acid, the solution became slightly turbid at 130°, and then, at 152° F., long 

 and slender colourless crystals began to form in it. The crystals increased in size 

 until the temperature had risen to 160° F., when also the turbidity of the solution 

 greatly diminished. After allowing the solution to become cold, 34*9 per cent, of 

 crystals were obtained, and the colourless filtrate was found to contain from 15 to 16 

 per cent, of glucose. (Table XL Analysis No. 36.) 



Strophanthin dissolved in 1 *5 per cent, sulphuric acid was allowed to stand in the 

 cold. On the following day, a small crystalline nodule and tuft, both consisting of 

 colourless transparent crystals, had formed at the bottom of the flask. On the third 

 day, several large nodules or rosettes had formed, the crystals of which had to the 

 naked eye an acicular lancet-shape (Plate VII. fig. 10).* The crystals were collected 

 and dried on the fourth day, when they weighed 37 '5 8 per cent, of the strophanthin 

 used. The filtered solution was divided into two portions. In one of them the glucose 

 was found to be 21 '3 per cent. The second portion was boiled for four hours; during 



* The crystals formed at the bottom of the flask have been represented, unmagnified, in PI. VII. fig. 10, as they 

 appeared on looking down upon them through the fluid in the flask. 



