From Math. Dekt.
For Grad. # 3
6-5-1923

THE PHILLIPS-LOOMIS MATHEMATICAL SERIES.

ELEMENTS OF GEOMETRY. By ANDREW W. PHILLIPS, Ph.D.,
and IRVING FISHER, Ph.D., Professors in Yale University. With an
Appendix treating of Plane Curves and Plane Figures, Exercises in
Plane and Solid Geometry, and Introduction to Modern Geometry, etc.
Crown 8vo, Half Leather, $1 75. [By mail, $1 92.]

ABRIDGED EDITION. Crown 8vo, $1 25. [By mail, $1 40.]

PLANE GEOMETRY. By ANDREW W. PHILLIPS, Ph.D., and IRVING
FISHER, Ph.D. Crown 8vo, Cloth, 80 cents. [By mail, 90 cents.]
KEY TO THE ELEMENTS OF GEOMETRY. (In Press.)
LOGARITHMS OF NUMBERS.

Five-Figure Table to Accompany
the "Elements of Geometry," by ANDREW W. PHILLIPS, Ph.D., and
IRVING FISHER, Ph.D., Professors in Yale University. Crown 8vo,
Cloth, 30 cents. [By mail, 35 cents.]

PUBLISHED BY HARPER & BROTHERS, NEW YORK.

Copyright, 1897, by HARPER & BROTHERS.

All rights reserved.

PREFACE

THIS book is an abridgment of the authors' "Elements of Geometry," and has been made for those schools whose course of study in this subject does not admit of the use of a more extended work.

The following are some of its more important features:

The Introduction presents in the shortest possible compass the general outlines of the science to be studied, and leads at once to the actual study itself.

The definitions are distributed through the book as they are needed, instead of being grouped in long lists many pages in advance of the propositions to which they apply. An alphabetical index is added for easy reference.

The constructions in the Plane Geometry are also distributed, so that the student is taught how to make a figure at the same time that he is required to use it in demonstration.

In the Geometry of Space, the figures consist of half-tone engravings from the photographs of actual models recently constructed for use in the class-rooms of Yale University. By the side of these models are skeleton diagrams for the student to copy.

Extensive use has been made of natural and symmetrical methods of demonstration. Such methods are used for deducing the formula for the sum of the angles of a triangle, for the sum of the exterior and interior angles of a polygon, for parallel lines, for the theorems on regular polygons, and for similar figures.

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