The experiment is carried out as follows: 3 or 4 grammes of the wax
that has been melted in water are put in 20 c.c. of neutral 95 per
cent, alcohol, and warmed until the wax melts, when phenolphthaleine
is added, and enough of an alcoholic solution of potash run in from a
burette until on shaking it retains a faint but permanent red color.
The burette used by the author is divided in 0.05 c.c. After adding 20
c.c. more of a half normal potash solution, it is heated on a water
bath for 3/4 hour. Then the uncombined excess of alkali is titrated with
half normal hydrochloric acid. The alcohol must be tested as to its
reaction before using it, and carefully neutralized with the acid of
phenolphthalein.
To saturate the free acid in 1 gramme of wax requires 19 to 21
milligrammes of potassic hydrate, while 73 to 76 milligrammes more are
necessary to saponify the myricine ether. The lower numbers in the one
usually occur with low numbers for the other, so that the proportions
remain 1 to 3.6 or 1 to 3.8.
For comparison he gives the following numbers obtained with one gramme
of the more common adulterants:
----------------+----------+----------+---------+--------+
| To | To | Total | |
|neutralize| convert |saponifi-| |
| the acid.
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