The commercial hand-book of chemical analysis : or, practical instructions for the determination of the intrinsic or commercial value of substances used in manufactures, in trades, and in the arts

Front matter

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Preface

Vll chemist or to the advanced chemical student ; they require a previous competent knowledge of the science, and do not afford the slightest assistance to those who, not being very conversant with chemical matters, only wish to ascertain the purity or the actual amount of available matter contained in the substances manufactured or purchased by them.

In the same manner as a treatise of analytical chemistry indicates the methods by which compounds in general can be distinguished from each other, and their quantity determined, the ‘ Commercial Hand-book of Chemical Analysis ’ is intended to show the specific application of these methods to compounds of a particular kind, and in which the operator may have to examine whether they are contaminated by impurities, or sophisticated by fraudulent additions, and to what extent ; or, in fact, whether the constituents known to exist in the genuine article are present, and in the proper degree.

In order to facilitate research, all the substances treated of have been put in alphabetical order ; and several of these compounds being known under various names, they have been entered under all these names in their respective order, the reader being at the same time referred to the more modern appellation for the information required.

EDITOR’S PREFACE

TO

THE PRESENT EDITION.

KX

In this New Edition the alphabetical order of the substances treated of in the former has been retained. Every article has been carefully revised, and the latest processes for detecting impurities have been given. Many of the articles

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PREFACE.

bearing on the sophistication of substances of domestic consumption, e.g., bread , beer, butter , cheese , milk, tea, water , wine, &c., have been greatly enlarged, and some new ones bave been added.

As it has been my wish to make the work a ‘ Handy Book ’ not only for the efficient analyst discharging his duties under the new Adulterations Act, but for others also less conversant with the details of chemical analysis, a considerable development has been given to the 1 Glossary,’ which will be found to contain much new matter on the subject of ‘ Chemical Manipulation,’ illustrated by many new and appropriate woodcuts ; whilst, as the design of the book is altogether practical, the different processes are, as in the former edition, described in plain language and without the employment of chemical symbols and notation.

Henry M. Hoad.

St. George’s Hospital : February 1875.