second distillate. At the end of this time, the distillation
is stopped, the water poured off from the distilling flask
and the tarry material emptied out while hot into waste jars.
The total amount of original reaction mixture requires
five distillations similar to the one just described.
The first distillates from each of the five distillations are mixed,
and the layer of mesitylene is separated from the water.
This is shaken with sodium hydroxide solution until no more odor of sulfur
dioxide is noticeable, then washed twice with water and distilled.
The first portion of the distillate consists of a small amount of water
and mesitylene and is added to the combined second distillates.
The fraction which distils up to 210'0 is saved. The second distillates
are combined, washed in the same way as the first and then distilled;
the fraction which distils up to 210'0 is combined with the corresponding
fraction from the first distillates.

These combined fractions (which boil up to 210'0) and 15 g.
of sodium are placed in a 2-l. distilling flask, the side-arm of
which is closed with a rubber tube and pinchcock and which is fitted
with a reflux condenser. The mixture is heated just below the boiling
point for about three hours, during which time the impurities are
attacked by the molten sodium, and a gelatinous, reddish mass forms.
The reflux condenser is now removed and one set for downward
distillation is attached to the side-arm. The mixture is distilled
and about two-thirds of the liquid removed in this way.
The residue is cooled, the liquid poured off from solid material
and distilled up to 210'0.

The distillates from the sodium treatment are now fractionated with
a good column (at least 30 cm. long), and the portion which boils