FIGURE, MAGNITUDE, AND MOTION OF THE EARTH;

WITH THE

NATURAL CHANGES ON ITS SURFACE,

Caused by Floods, Earthquakes, &c.,

TOGETHER WITH

THE ELEMENTARY PRINCIPLES OF METEOROLOGY AND
ASTRONOMY, THE THEORY OF TIDES, &c.

PRECEDED BY

AN EXTENSIVE SELECTION OF ASTRONOMICAL AND OTHER DEFINITIONS;
AND ILLUSTRATED BY A GREAT VARIETY OF PROBLEMS, QUESTIONS
FOR THE EXAMINATION OF THE STUDENT, &c.

DESIGNED FOR THE INSTRUCTION OF YOUTH.

BY THOMAS KEITH.

A New Edition, Enlarged and Emproved,

BY THE

REV. G. N. WRIGHT, M.A.,

Author of "Euclid in General Terms;" Editor of "Mangnall's Historical Questions," &c.

LONDON:

WILLIAM TEGG AND Co., 85, QUEEN STREET,

PUBLIC LIBRARY

93213

ASTOR, LENOX AND
TILDEN FOUNDATIONS.

1898

J. HADDON AND SON, PRINTERS, CASTLE STREET, FINSBURY,

PREFACE

OF THE PUBLISHERS.

THE discoveries of modern Astronomers, in addition to the important truths that have been unfolded by the labours of scientific men in later years, have called for many alterations in the arrangement of Mr. Keith's work, and given occasion for the introduction of much new and necessary matter. Amongst the improvements which the Publishers claim the merit of introducing into this edition, are directions, which will enable the attentive student to discover and distinguish, satisfactorily, the various constellations in the heavens : -A full account of the principal astronomical instruments required and used in observatories :-A chapter on time and its divisions, with a succinct history of the mutations of our calendar.

Very many corrections and interpolations have been