Prepared Under the Direction of the Joint Executive VOLUME I ARITHMETIC, ELEMENTARY APPLIED MATHEMATICS, BY J. J. CLARK, M.E. FIRST EDITION MCGRAW-HILL BOOK COMPANY, INC. NEW YORK: 370 SEVENTH AVENUE 1921 COPYRIGHT, 1921, BY THE JOINT EXECUTIVE COMMITTEE OF THE VOCATIONAL EDUCATION COMMITTEES OF THE PULP AND PAPER INDUSTRY ALL RIGHTS RESERVED, THE MAPLE PRESS YORK PA PREFACE In numerous communities where night schools and extension classes have been started or planned, or where men wished to study privately, there has been difficulty in finding suitable textbooks. No books were available in English, which brought together the fundamental subjects of mathematics and elementary science and the principles and practice of pulp and paper manufacture. Books that treated of the processes employed in this industry were too technical, too general, out of date, or so descriptive of European machinery and practice as to be unsuitable for use on this Continent. Furthermore, a textbook was required that would supply the need of the man who must study at home because he could not or would not attend classes. Successful men are constantly studying; and it is only by studying that they continue to be successful. There are many men, from acid maker and reel-boy to superintendent and manager, who want to learn more about the industry that gives them a livelihood and by study to fit themselves for promotion and increased earning power. Pulp and paper makers want to understand the work they are doing the how and why of all the various processes. Most operations in this industry are, to some degree, technical, being essentially either mechanical or chemical. It is necessary, therefore, that the person who aspires to understand these processes should obtain a knowledge of the underlying laws of Nature through the study of the elementary sciences and mathematics, and be trained to reason clearly and logically. After considerable study of the situation by the Committee on Education for the Technical Section of the Canadian Pulp and Paper Association and the Committee on Vocational Education for the Technical Association of the (U. S.) Pulp and Paper Industry, a joint meeting of these committees was held in Buffalo |