DR THOMAS R. FRASER ON STROPHANTHUS HISPIDUS. 



1015 



boiling it evolved a cooked raisin odour, became turbid, and, when cooled, deposited 

 a yellowish-brown amorphous substance, all of which was not collected. The filtrate of 

 the second portion was slightly coloured and only faintly bitter ; and 26*65 per cent, of 

 glucose was found in it by Fehling's reagent, and 23 '64 by fermentation. (Table XL 

 Analysis No. 40.) 



A summary of the preceding and of several other experiments is given in Table XL 



Table XI. — Summary of Analyses in which Strophanthin was decomposed by Sulphuric Acid. 



o •*> 



Quantity 

 of Stro- 

 phanthin 



in 

 Grammes. 



Per- 

 centage 

 of Stro- 



Per- 

 centage 

 of Sul- 



Strophanthidin pro- 



Glucose pro- 

 duced in the 



Strophanthidin produced after 



Glucose produced 



6 "rt 

 S3 a 



phanthin 

 in Solu- 

 tion. 



phuric 

 Acid. 



duced in the Cold. 



Cold. 



Heating. 



after Heating. 



34 



0-25 



3-3% 



33% 



In six days, 33 7 % 

 of crystalline stro- 

 phanthidin. 



22% 







35 



0-25 



3-3% 



0-33% 







After boiling for half an hour, 

 36 '2 % of crystalline strophan- 

 thidin. 



After boiling for 

 half an hour, 

 27-5 %. 



36 



0-25 



2-5% 



0-5% 







After heating to 160° F., 34 9 % 

 of crystalline strophanthidin. 



After heating to 

 160° F., 15 %. 



37 



0-25 



2-5% 



0-5% 







After heating to 170° F., 32-14 % 

 of crystalline strophanthidin. 



After heating to 

 170° F., 16 5%. 



38 



25 



2-5% 



0-5% 







After boiling for half an hour, 

 22'3 % of strophanthidin, chiefly 

 in round particles. 



After boiling for 

 half an hour, 

 21-2 %. 



39 



0-5 



3-3% 



1'3% 



In five days, 37 "5 



In five days, 



After boiling one half of the fil- 



After boiling one 











% of crystalline 



19%. 



tered solution for four hours, 



half of the filtered 











strophanthidin. 





4*6 per cent, of amorphous 

 yellowish-brown substance. 



solution for four 

 hours, 24-6 %. 



40 



0-5 



3-3% 



1-5% 



In four days, 37 '58 



In four days, 



After boiling one half of the 



After boiling one 











% of crystalline 



21-3%. 



filtered solution for four hours, 



half of the filtered 











strophanthidin. 





4 - 3 % of yellowish-brown amor- 

 phous substance. 



solution for four 

 hours, 26-65% by 

 Fehling's reagent, 

 and 23-64 % by 

 fermentation. 



41 



0-25 



3"5% 



2% 







After boiling for half an hour, 

 377 % of yellowish-brown 

 amorphous substance. 



After boiling for 

 half an hour, 

 22-02 %. 



Sulphuric acid was the only acid employed to decompose strophanthin ; as it seemed 

 unnecessary, for the present purpose, to multiply the experiments, in view of the evidence 

 already described regarding the action of other acids on the extract of strophanthus, 

 there being no reason to doubt that the decomposition of strophanthin into glucose and 

 strophanthidin will occur under the influence of those other acids which have been 

 shown to decompose strophanthin in the extract. 



It is seen from the analyses summarised in the above Table (XL) that large quantities 

 of crystalline strophanthidin, and considerable quantities of glucose, were produced by the 

 prolonged contact in the cold of strophanthin with from 0'3 to 1*5 per cent, sulphuric 

 acid. Crystalline strophanthidin was also abundantly produced when strophanthin was 

 boiled for a short time with "3 per cent, sulphuric acid ; and much crystalline strophan- 

 thidin, but proportionally less glucose, when strophanthin was heated between 160° and 



