BYRNE'S

DOCTRINE OF PROPORTION.

DOCTRINE OF PROPORTION

CLEARLY DEVELOPED,

ON A COMPREHENSIVE, ORIGINAL, AND

VERY EASY SYSTEM ;

OR,

THE FIFTH BOOK OF EUCLID

SIMPLIFIED.

BY

OLIVER BYRNE,

PROFESSOR OF MATHEMATICS, COLLEGE FOR CIVIL ENGINEERS; CONSULTING
ACTUARY TO THE PHILANTHROPIC LIFE ASSURANCE SOCIETY.

AUTHOR OF
THE NEW AND IMPROVED SYSTEM OF LOGARITHMS;" “ THE PRACTICAL, COMPLETE,
AND CORRECT GAGER; ;" "A TREATISE ON SPHERICAL TRIGONOMETRY; “ THE
ELEMENTS OF EUCLID, BY COLOURS;” “HOW TO MEASURE THE
LENGTH OF A DEGREE ON THE EARTH'S SURFACE, WITH
THE ASSISTANCE OF RAILROADS;” ETC., ETC.

INVENTOR OF
“ THE GAGER'S PATENT CALCULATING INSTRUMENTS;” “ THE SYSTEM OF FACILITATING THE
ACQUIREMENT OF GEOMETRY, AND OTHER LINEAL ARTS AND SCIENCES,

BY COLOURED DIAGRAMS; ETC., ETC., ETC.

London:

J. WILLIAMS, LIBRARY OF ARTS,

No. 106, GREAT RUSSELL STREET, BLOOMSBURY.

MDCCCXLI.