larger works on analytical chemistry. The author is indebted to the
standard works for many suggestions for which it is impracticable to
make specific acknowledgment; no considerable credit is claimed by him
for originality of procedure.

For many years, as a matter of convenience, the classes for which this
text was originally prepared were divided, one part beginning with
gravimetric processes and the other with volumetric analyses. After a
careful review of the experience thus gained the conclusion has been
reached that volumetric analysis offers the better approach to the
subject. Accordingly the arrangement of the present (the sixth)
edition of this manual has been changed to introduce volumetric
procedures first. Teachers who are familiar with earlier editions
will, however, find that the order of presentation of the material
under the various divisions is nearly the same as that previously
followed, and those who may still prefer to begin the course of
instruction with gravimetric processes will, it is believed, be able
to follow that order without difficulty.

Procedures for the determination of sulphur in insoluble sulphates,
for the determination of copper in copper ores by iodometric methods,
for the determination of iron by permanganate in hydrochloric acid
solutions, and for the standardization of potassium permanganate
solutions using sodium oxalate as a standard, and of thiosulphate
solutions using copper as a standard, have been added. The
determination of silica in silicates decomposable by acids, as a
separate procedure, has been omitted.

The explanatory notes have been rearranged to bring them into closer
association with the procedures to which they relate. The number of