ON A RED RESIN FROM DRACAINA CINNABARI. 625 
entirely sublimable, while no sublimate was given by the extract obtained by 
digesting the resin to which no acid had been added. In the latter case the 
extract, which is very small, appears to consist of a trace of oily matter and a 
little resin. The resin, indeed, is soluble in these and in nearly every other re- 
agent, with the exception of petroleum ether, to a very slight extent. When 
heated the resin loses somewhat in weight, the loss being due to the expulsion 
of moisture. 
Caustic potash and soda completely dissolve the resin to an orange-red 
coloured solution ; aqueous ammonia and lime water have nearly the same 
action upon it. Cold sodium carbonate dissolves it to a blood-red solution, which 
’ changes to orange red on boiling. Acetate of lead precipitates from the alcoholic 
solution a mauve coloured salt, which is insoluble in boiling water but readily 
soluble in alcohol. Three analyses of this salt gave the following numbers :—(1) 
25°33, (2) 25°27, and (8) 25°17 per cent. of lead. The first of these determinations 
was made by simply treating the salt with strong sulphuric acid, evaporating down 
and igniting, the other two by acting upon the salt with strong nitric acid, and 
precipitating the lead with sulphuric acid. This is the only definite salt that 
we have as yet succeeded in preparing. Nitric acid completely decomposes the 
resin. Hydrochloric acid dissolves it to a slight extent, ammonia reprecipitat- 
ing it. Acetic acid, in which it dissolves abundantly, gives an orange-red solu- 
tion, from which also the resin can be reprecipitated by ammonia. Having 
carefully purified the resin by repeated solution in ether, we burned it, with the 
following results :— 
3) (4) 
( 
C 71:22 72°80 70°28 72°02 
ic Re as . 5694 6:02 5°93 6°43 
O 22°84 21:18 23°79 21°55 
100-00 100:00 100-00 100-00 
The average of these four analyses is C 71°58, H 6:08, and O 22°34. 
Owing to the great difficulty in thoroughly purifying resinous bodies these 
numbers can only be regarded as approximately accurate ; they correspond very 
closely, however, with the formula C,;H,,0,. A substance having this formula 
would contain 72°48 per cent. of carbon, 6°04 per cent. of hydrogen, and 21:47 
per cent. of oxygen, and would have a combining weight of 298. This agrees 
very closely with the results obtained by the analysis of the lead salt. Assum- 
ing the acid to be monobasic, the composition of this salt would be (C,sH1;O,). Pb, 
and a salt having this composition would contain 25°84 per cent. of lead. 
The percentage of lead actually found, taking the mean of three experiments, 
was 25°25. 
Having ascertained the properties and ultimate composition of the resin 
from Dracena Cinnabari, we proceeded to compare it with other varieties of 
