By ALEXANDER WATT

AUTHOR OF "THE ART OF SOAP-MAKING," "LEATHER MANUFACTURE," "ELECTRO-METALLURGY," "ELECTRO-DEPOSITION," ETC., ETC.

LONDON
CROSBY LOCKWOOD AND SON
7, STATIONERS' HALL COURT, LUDGATE HILL
1890
[All rights reserved]


LONDON:
PRINTED BY J. S. VIRTUE AND CO., LIMITED.
CITY ROAD.


PREFACE.