376 
MR. JOHNSTON ON THE CONSTITUTION OF THE RESINS. 
C. Ether now digested on the mass, already treated with alcohol, gave a resin 
which, after long heating at 180° Fahr., left 0*39 per cent, of ash, and 
5*85 grs. (5*827 grs. pure resin) gave C = 15*17, and H = 3*575 grs. 
D. Ether was again digested on the residual resin, the solution evaporated, and 
the film long heated at 250° Fahr. 
5*77 grs. (5*75 grs. pure resin) gave C = 15*01, and H = 3*48 grs. 
These several results are equivalent to 
By alcohol. By ether. 
A (15). 
B (16). 
C (17). 
D (18). 
Carbon 
72*73 
71*39 
71*99 
72*18 
Hydrogen 
7*49 
7*18 
6*82 
6*72 
Oxygen 
19*78 
21*43 
21*19 
21*10 
100 
100 
100 
100 
These analyses show that the mass thus treated successively with alcohol and 
ether, was a mixture of at least two resins, of which the more soluble was the first 
taken up, and contained most hydrogen. The results of analysis A. agree very nearly 
with those obtained for the resin C 40 IT 24 O g , produced by the action of quicklime on 
the crude resin, and the portion first taken up by the alcohol may have consisted 
chiefly of that resin. Analysis B. again, coincides very closely with the formula 
C 40 0 9 , which we have also formerly obtained. But these coincidences may be 
accidental, and it is the successive portions taken up by the ether, which give analo- 
gous results, that we are to consider as approaching nearest to the resin in its pro- 
bably normal state. These results agree with the formula C 40 H 22 0 9 , which gives 
Carbon 
Calculated. 
72*24 
Found (17.) 
71*99 
(18.) 
72*18 
Hydrogen 6*48 
6*82 
6*72 
Oxygen 
21*28 
21*19 
21*10 
100 
100 
100 
Besides the admixture of the resin C 40 H 24 0 8 above supposed, there may have been 
present in the mass, a portion also of the resin about to be described. 
2. The alcoholic solution which remained after precipitating the crude resin as 
above described, was diluted with water, by which only a small quantity of resin was 
precipitated. The filtered solution was then decomposed by excess of muriatic acid, 
and the precipitated resin well washed with copious affusions of hot water, by which 
the resinous powder was not melted or made to cohere. It was then collected on the 
filter, dried at 212° Fahr., dissolved in alcohol, filtered, and again evaporated, and 
dried at a gentle heat. It left 0*2 per cent, of ash. 
Four several portions of the same alcoholic solution were thus evaporated and ana- 
lysed in succession : — 
