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XIX. On the Constitution of the Resins. Part V. By James F. W. Johnston, Esq., 
M.A., F.R.S., Professor of Chemistry and Mineralogy in the University of Durham. 
Received June 4, — Read June 18, 1840. 
XVII. Resin of Sagapenum. 
The gum resin of sagapenum has an odour very much resembling that of assafoe- 
tida, but less powerful. Like the latter gum resin, it also gives, when treated with 
alcohol, a pale yellow solution, while the greater portion of the mass remains undis- 
solved. The white matter which is left behind after exhaustion with alcohol, is 
soluble in water, giving a milky solution. 
The alcoholic solution, when evaporated, gives a pale-yellow resin, having a strong 
garlic odour, melting readily, and becoming fluid at 212° Fahr. 
A portion of the resin prepared by evaporating the alcoholic solution at 212°, was 
treated for two hours with repeated portions of boiling water. The water came oft’ 
colourless, but had a powerful odour of the resin, and a slightly bitter taste, leaving 
in the mouth an after-taste of onions. After drying it for a length of time at 212°, 
the resin was again dissolved in alcohol, filtered and evaporated in a thin film. It 
was then heated at 150° Fahr. for sixty hours, at which temperature it was still 
semifluid. 
Burned in the air it left 022 per cent, of ash. 
A. 8‘585 grs. (8‘566 grs. of pure resin) gave C = 21-170, and H = 6-558 grs. 
B. Further fused at 212° Fahr. for several hours, the colour became deeper yellow 
than before. When cold it was brittle but soft, and the particles readily cohered. 
In this state 
10T1 grs. (10-088 grs. pure resin) gave C = 25’84, and H = 7‘8 35 grs. 
These results give per cent. 
Carbon 
A. 
70-05 
B. 
70-83 
C, 0 H 2 p 0 9 , gives 
70-78 
Hydrogen 
8-51 
8-63 
8-38 
Oxygen 
21-44 
20-54 
20-84 
100 
100 
100 
We may, therefore, consider the resin of sagapenum thus extracted, to be repre- 
sented by C 40 H 29 0 9 . 
MDCCCXL. 3 A 
