Applied chemistry : in manufactures, arts and domestic economy

Preface

The " Preliminary Observations," with which this volume commences, comprise some brief considerations on the fundamental doctrines of chemistry, motst of which may be included in an account of the general laws which govern, and the phenomena and changes which accompany, the chemical combination of different bodies. This introduction concludes with an explanation of Chemical Symbols, and a table of Equivalents.

The article on Gas Illumination comprises not only a detailed account of the process of making light-gas from coal, and of the chemical and physical properties of the constituents of coal-gas, but several important collateral subjects; among which are some considerations on the modes of burning gas and on the economy of gas illumination, descriptions of the processes for making light-gas from other sources than coal, and an account of the applications which the secondary products of the coal-gas manufacture have received. The construction of different kinds of regulators and meters, and the process of " naphthalizing" gas, are also considered.

In the article on the Preservation of Wood, which follows that on Gas Illumination, means are pointed out for effectually guarding against the ordinary devi

PREFACE.

composing influences of air and water on timber. A considerable portion of the article is devoted to an account of the important experiments of Mr, W. Hyett, on the effects of the impregnation of wood with foreign substances.

Dyeing and Calico-printing forms the comprehensive subject of the concluding article of the present volume. Most of the leading processes now practised by the calico-printers of this country are there described, accompanied with explanations of the scientific principles on which they are based. Sereral of these processes, new to treatises on the subject, will be found of considerable value.

In many parts of the article on Calico-printing, I have derived material assistance from my esteemed friend Mr. Mercer, of the Oakenshaw print-works, near Blackburn, to whom I feel myself bound to return my sincere thanks. I am also desirous of expressing my obligations to Mr. John Graham of the Mayfield print-works, Manchester; and to Mr. James Hindle of the Sabden works, near Wlialley,

Table Of Contents

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Attainments of the ancients in some chemical arts. — Probably acquired by chance. — Processes mostly devised and improved now by deductions from principles. — Theoretical principles may be erroneous and the processes successful. — A few valuable processes discovered accidentally in modern times. — Amalgamation process of Hernando Velasquez ..... 1

Elements,— Difference between a chemical compound and a mechanical compound ...... 8