modern agricultural mathematics

327 Pages·2013·8.06 MB·English

MODERN AGRICULTURAL MATHEMATICS

MODERN AGRICULTURAL
M A T H E M A T I CS
A Textbook for Students oi Agriculture in High Schools,
Vocational Schools, and Rural Schools; and a Handy Refer
ence Book for Farmers and Other Workers in the Various
Branches of Agriculture, Containing Methods of Calculation
for All Types of Agricultural Problems
By
MAURICE NADLER, B.S., A.M.
Department of Mathematics
Agricultural Division of Newtown High School,
Long Island
^fLLUSTRATED
NEW YORK
ORANGE JUDD PUBLISHING COMPANY, INC.
1946
COPYRIGHT, 1940, BY
ORANGE JUDD PUBLISHING COMPANY, INC.
PRINTED IN THE UNITED STATES OF AMERICA
This book or any part thereof may not be
reproduced without permission of the
publishers, except by a reviewer who
wishes to quote brief passages in connec
tion with a review for inclusion in a mag
azine or newspaper
Copyright under the Articles of the Copyright Convention
of the Pan American Repubhcs and the
United States, August 11, 1910
PREFACE
THE use of mathematics is essential in many farm activities.
This book contains selected portions of the broad field of
mathematical knowledge sufficient, in the opinion of the author,
for the needs of the agricultural student and worker. The text
is appropriate for those who have already learned the funda
mental operations of computation, namely, addition, subtrac
tion, multiplication and division of whole numbers, fractions
and decimals, as taught in the standard program of arithmetic
in elementary schools. One school year should be spent for the
completion of this course in agricultural mathematics. The
book is divided into two parts, each of which is intended for
one half-year of study.
In general, three aims are fostered. First, it is desired to im
part an understanding of the development and structure of the
subject of mathematics. Second, the student is trained in the
analysis of problems, and in the application of mathematical
processes to their solution. Third, the book teaches the meth
ods of solution of all types of mathematical problems arising
in connection with the many branches of agriculture.
Part I of the book seeks to develop by logical steps the vari
ous rules and formulas used in the measurement of length, di
rection, area, volume, and also specific relationships between
different units of measure. In the course of this procedure,
the student will become acquainted with some algebra, geom
etry and trigonometry. However, material is avoided that may
be too difficult for a student whose entire mathematical back
ground consists of rudimentary arithmetic. The author has
also kept in full view throughout the text the applications to
agriculture. Each small unit of mathematics presented is fol
lowed by a series of farm problems. Certain applications have
been given special attention, as for example, Crops and Or-
PREFACE
VI
chards, and the Measurement of Lumber and Timber, which
have been treated as separate topics. ^
Scientific methods are imperative for success in modern
farming. Moreover, a reasonable financial return is dependent
upon competent business practices. Expert computation is an
important aid in both of these aspects of farm management.
The detailed consideration of dairying, the feeding of farm ani
mals, soil fertility, fertilizers, farm mechanics, and finance and
management, in Part II of the text, provides the necessary
skills in calculation. Despite the wide selection of examples,
the farmer may sometimes be confronted with problems not in
cluded in this book. The author expects that the readers will
have acquired sufficient power in mathematics to be able to
solve such new types of examples that may arise in their work.
Arithmetic drills, reference tables and answers to problems,
are contained in the appendix. The body of the book includes
sample solutions of problems, projects in measurement, and
lists- of references. The author is hopeful that the entire text
will be of great assistance to the many people training for or
now engaged in agricultural pursuits.
Credit is due the late Principal James D. Dillingham and
Principal Alfred S. Roberts, and their associates, who have nur
tured the Agricultural Division of Newtown High School, un
der the auspices of the Board of Education of the City of New
York. It is in this school that the author has experimented
with the course of Farm Mathematics, finally culminating in
the subject matter included in this book.
The author is indebted to Clara C. Eaton, Head of the Math
ematics Department of Newtown High School, for her many
valuable suggestions; and to Clinton E. Skifstad, Teacher-in-
charge, Robert P. Armstrong, William A. Morgan and C.
Laurin March, of the Agricultural Department, for their help
ful contributions.
Grateful appreciation is acknowledged to the United States
Department of Agriculture and to the State Agricultural Ex
periment Stations cited in this book, and members of the staffs,
for their information, illustrations, and tables.
PREFACE vii
Indebtedness is acknowledged to the Portland Cement As
sociation, for the use of the illustrations reproduced on pages
74, 197, 228, 229 and 230; to the Lafayette Instruments Com
pany for those on pages 7, 10, and 17; to the De Laval Separa
tor Company, for the illustration on page 141; to the Holstein
FriesiSn Association of America, for the illustration on page
136; to the American Jersey Cattle Club, for the illustration
on page 139; and to the various other sources of illustrations
acknowledged in this book.
The author expresses his deep appreciation to Florence E.
Nadler, for her invaluable aid in the preparation of the manu
script and in the proofreading.
MAURicfi NADLER.

TABLE OF CONTENTS
Part I
CHAPTER PAGE
I. MEASUREMENT OF LENGTH 1
II. MEASUREMENT OF DIRECTION . . . . . . .. 10
III. MEASUREMENT OF AREAS 20
IV. PRACTICAL LAND MEASUREMENT . . . . . .. 35
V. THE PLANTING OF CROPS AND ORCHARDS . . . .. 46
VI. MEASUREMENT OF VOLUME 57
VII. MEASUREMENT OF CIRCULAR AND CYLINDRICAL
OBJECTS 66
VIII. THE DRAWING OF FARM PLANS . . . . . .. 80
IX. MEASUREMENT OF LUMBER AND TIMBER . . . .. 89
X. RATIO AND PROPORTION 101
XI. THE RULE OF THE RIGHT TRIANGLE . . . . . . 117
XII. REVIEW OF PERCENTAGE 124
Part II
XIII. DAIRYING . . . ." 132
XIV. THE STANDARDIZATION OF DAIRY PRODUCTS . . . 148
XV. FEEDS . . . IS6
XVI. THE FEEDING OF FARM ANIMALS . . . . . .. 166
XVII. SOIL FERTILITY 183
ix
X CONTENTS
CHAPTER PAGE
XVIII. FARM MANURE AND COMMERCIAL FERTILIZER . . . 196
XIX. FARM POWER AND MECHANICS 213
XX. CONCRETE CONSTRUCTION 228
XXI. FARM FINANCES 238
XXII. THE BUSINESS MANAGEMENT OF FARMING . . .. 246
XXIII. GRAPHS 258
Appendix
ARITHMETIC DRILLS 269
TABLES OF MEASURES 277
FORMULAS AND RULES 278
REFERENCE TABLES 280
ANSWERS TO PROBLEMS AND DRILLS 299
INDEX 311