12° B. strong, and frequently stirred with a glass rod. The wool fiber
soon dissolves in the potash lye, while the vegetable fiber remains
unaltered. The pulpy mass resulting is placed upon a filter, dried at
212° Fahrenheit, and after the potash lye has dripped off, the
residue, consisting of vegetable fiber and earthy ash ingredients, is
washed until the water ceases to dissolve anything. The residue dried
at 212° Fahrenheit is weighed with a filter, after which that of the
latter is deducted. The loss of weight experienced is essentially
equal to the loss of the wool fiber. If the filtrate is saturated with
hydrochloric acid, the dissolved wool fiber separates again, and after
having been collected upon a weighed filter, it may be weighed and the
quantity ascertained.

The weight of the mineral substances in the raw paper is ascertained
by analyzing the ash in a manner similar to that above described. The
several constituents of the ash and the mineral added to the raw paper
are ascertained as follows: Sufficient of the paper is calcined in the
manner described; a known quantity of the ash is weighed and thrown
into a small porcelain dish containing a little distilled water and an
excess of chemically pure hydrochloric acid. In this solution are
dissolved the carbonates, carbonate of lime, carbonate of magnesia, a
little of sulphate of alumina, as well as metallic oxides, while
silicate of magnesia, silicic acid, sulphate of lime (gypsum) remain
undissolved. The substance is heated until the water and excess of
free hydrochloric acid have been driven off; it is then moistened with
a little hydrochloric acid, diluted with distilled water and heated.
The undissolved residue is by filtering separated from the dissolved,
the filter washed with distilled water, and the wash water added to
the filtrate. The undissolved residue is dried, and after the filter
has also been burned in due manner and the ash added, the weight is