RESINS 23 
of half-normal alcoholic potash were then added and the mixture 
heated on a steam bath (refluxed) for an hour. The excess of 
potassium hydroxide was titrated with a half-normal alcoholic 
solution of hydrogen chloride. A gram of surface resin required 
approximately 177 milligrams of potassium hydroxide for neu- 
tralization, while a gram of fossil resin took about 150 milli- 
grams. The acid and saponification values of various samples 
of resin were determined. The results showed that darker speci- 
mens of resin gave higher acid and saponification values than 
did lighter-colored ones. 
Samples of surface resin were distilled with steam, but only 
traces of volatile oil were obtained. Fossil resin which was 
finely pulverized yielded a larger proportion of volatile oil. 
When steam-distilled in the presence of an alkali, 500 grams 
of surface resin gave 6.5 grams of oil, while an equal quantity 
of fossil resin gave 40 grams of oil. The oil obtained by steam 
distillation when dried over solid potassium hydroxide had a 
pale-lemon color and pleasant odor. This was fractionally dis- 
tilled. The main fraction boiled between 155° and 165°. By 
treating with hydrochloric acid gas this fraction was converted 
into a hydrochloride which crystallized from alcohol and melted 
at 124°. This substance was identified as pinene hydrochloride. 
A method of analysis devised by Richmond showed that one 
hundred parts of crude resin gave the following results: 
insolublean= absolute: alcohnolie 2 Ses ee 5 
Solwuie in, alcohaene potash. Ss ...2e S h k . 40.0 
fasoluple in alcoholie -porash: 2.02 ee bic ee tee nce ae Al 5 
Neutral oil soluble in alcohol and volatile with steam.. 6.0 
Neutral resin partially soluble in alcohol and non- 
WOlatilemwdicMeSt@amm tse et eee se ese eeccas 10.0 
Water ete. undetermined: ... 20s... fe. ce eee 2.0 
These results confirm the conclusion of Tschirch that Manila 
copal consists mainly of amorphous free resin acids, and contains 
a neutral resin indifferent to alkalies, and a volatile oil. Rich- 
mond extracted the resin acids from Manila copal by using a 
modification of Tschirch’s method. An ether extract of Manila 
coral was treated with 5 per cent ammonium carbonate solution 
for several days, after which the mixture was acidified. The 
resin acids were precipitated as an amorphous powder. When 
this precipitate was dissolved in dilute alcohol and crystallized, 
white crystals melting at 186° were obtained. Analysis showed 
that these crystals had the molecular formula C,,H,,O, and that 
the resin acid was monobasic. 
