BY JAMES THOMSON, LL.D.

PROFESSOR OF MATHEMATICS IN GLASGOW COLLEGE;
AUTHOR OF ELEMENTS OF PLANE AND SPHERICAL TRIGONOMETRY;
INTRODUCTION 10 MODERN GEOGRAPHY; ETC.

Eighteenth Edition,

Adapted to the Present System of Weights, Measures, and Currency."

BELFAST:

STEREOTYPED AND PRINTED BY

SIMMS AND MINTYRE, DONEGALL STREET.