CHICAGO
AMERICAN SCHOOL OF CORRESPONDENCE
1908
Copyright 1907 by
American School of Correspondence
Entered at Stationers’ Hall, London
All Rights Reserved
Foreword
IN recent years, such marvelous advances have been made in the engineering and scientific fields, and so rapid has been the evolution of mechanical and constructive processes and methods, that a distinct need has been created for a series of practical working guides, of convenient size and low cost, embodying the accumulated results of experience and the most approved modern practice along a great variety of lines. To fill this acknowledged need, is the special purpose of the series of handbooks to which this volume belongs.
¶ In the preparation of this series, it has been the aim of the publishers to lay special stress on the practical side of each subject, as distinguished from mere theoretical or academic discussion. Each volume is written by a well-known expert of acknowledged authority in his special line, and is based on a most careful study of practical needs and up-to-date methods as developed under the conditions of actual practice in the field, the shop, the mill, the power house, the drafting room, the engine room, etc.