107 
so as to obtain increased pressure, there is formed by the 
influence of the alkali a resin which is insoluble in alkali. In 
a short time the liquid becomes red, and on the addition of 
water the resin is precipitated, the liquid becoming colourless. 
This takes place also when methylic alcohol is employed. 
The resins thus formed are of a red colour. 
After filtration and washing with water the resin was dis- 
solved in alcohol, and the residue, after evaporation, dried at 
100° C. When cold these resins are hard and brittle, but 
they have no crystalline structure. They are soluble in 
alcohol and ether. The resin formed from methylic alcohol 
melts at 59° C., the other at 65° C. The odour of the 
former is like that of cedar wood, while that of the latter 
more resembles the smell of oranges. In general there is a 
great resemblance between these resins and the natural 
resins, such as copal, &c. In employing methylic alcohol 
the formation of the resin takes place much more easily, 
and a greater quantity of product is obtained. I tried in 
various ways to decolorise the resins, but did not succeed. 
Through the alkaline liquid filtered from the resin a cur- 
rent of carbonic acid was passed, then it was evaporated, and 
the saline residue having been treated with sulphuric acid in 
excess, the liquid was distilled. The distillate was acid; 
silver solution was reduced by it in an instant, so that there 
was little doubt of the presence of formic acid (but the pecu- 
liar smell of propionic acid could not be perceived). 
From the analysis it must be inferred that the tw r o resins 
have the same composition ; but still, as their properties are 
not identical, I think they are only isomeric. 
The analysis afforded the following results : 
I. 0T860 grm. (methylic ale.) gave 0*5080 grm. carbonic 
acid and QT550 grm. water. 
II. 0*2465 grm. (methylic ale.) gave 0*6795 grm. carbonic 
acid and 0T965 grm. water. 
III. 0*2090 grm. (ethylic ale.) gave 0*5745 grm. carbonic 
acid and 0*1590 grm. water. 
