MR. JOHNSTON ON THE CONSTITUTION OF THE RESINS. 
373 
3. The above results not being satisfactory, I prepared a larger quantity of the resin. 
Twelve hundred grains were boiled in an iron kettle with a large quantity of slaked 
lime in fine powder, in repeated portions of water, till ten or twelve quarts had passed 
through the filter. The solution was pale yellow to the last, muriatic acid threw down 
from it a resin in white flocks, which in the last solutions was smaller in quantity. 
This precipitate was collected for subsequent examination. 
The compound with lime was, as before, of a purple colour, which became more 
bright and beautiful as the excess of lime was gradually removed by digestion with 
dilute muriatic acid. When completely decomposed by this acid, a yellow solution 
and a gray resinous powder were obtained. The powder was well washed, dried at 
212° Fahr., and then treated with alcohol. What remained undissolved was chiefly 
sand and earthy matter. The alcoholic solution, evaporated and dried in a thin film 
at 150° Fahr., gave a resin which, after heating several hours at 212° Fahr., left 0*904 
per cent, of ash, and 
A. 7*36 grs. (7’29 grs. pure resin) gave C — 18*69, and H = 4*83 grs. 
B. Heated further for several hours at 220° Fahr., 8*59 grs. (8*512 grs. pure resin) 
gave C = 22*49, and H = 5*695 grs. 
C. Further heated for twelve hours at 180° Fahr., 6*94 grs. (6*875 grs. pure resin) 
gave C = 1 8'2 1 , and H = 4*725 grs. 
D. Again heated to incipient fusion (300 + Fahr.), when the particles began to 
cohere, 7'53 grs. (7‘46 grs. pure resin) gave C = 19*735, and H = 4*925 grs. 
The following Table shows the result of these analyses of the three several portions 
of resin prepared by boiling with quicklime : — • 
First portion dried 
at 212°. 
Second portion. 
Third portion. 
Heated at 
212°. 
Longer at 180° 
Fahr. 
Heated at 
212°. 
Further at 
220° Fahr. 
Further 12 
hours at 180° 
Fahr. 
Further to in- 
cipient fusion 
(300° ?). 
7. 
8. 
9 
10. 
11. 
12. 
13. 
Carbon 70*97 
71*24 
72*13 
70*89 
73*07 
73*26 
73*15 
Hydrogen 7'38 
7*24 
7*01 
7*36 
7*43 
7*63 
7*34 
Oxygen 21*65 
21*52 
20*86 
21*75 
19*50 
19*11 
19*51 
100 
100 
100 
100 
100 
100 
100 
The identity of the last three results entitles us to place reliance upon them, as indi- 
cating very approximately the constitution of the resin in its normal (?) state. Com- 
paring these with the results obtained by the analyses 5 and 6 previously given, we see 
that the effect of prolonged boiling with quicklime is to bring the resin into the same 
state as when it is boiled with concentrated carbonate of soda. In the latter analyses, 
however, the experimental came still nearer to the calculated numbers given by the 
formula C 40 H 24 0 8 . Analysis 13 was undertaken in consequence of the discordance 
as to the amount of hydrogen between 1 1 and 1 2, and from the precautions taken, 
