THE

E L E M E N T S

OF

E U CL I D.

L I

V I Z.

THE FIRST SIX BOOKS,

TOGETHER WITH THE

ELEVENTH AND TWELFTH.

The Errors, by which Theon, or others, have long ago Vitiated

thefe Books, are Corrected,
And some of Euclid's Demonstrations are Restored.

BY
ROBERT SIMSON, M. D.
Emeritus Professor of Mathematics in the University

of Glasgow.

QA 451 ,S6 1762

(SION COLLEGE

LIBRARY