The Errors, by which THEON, or others, have long ago

vitiated these Books, are corrected,
And some of EUCLID's Demonstrations are restored.

A L S 0

THE BOOK OF

E UCL I D'S

DA TA, C

In like manner corrected.

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

To this FIFTH EDITION are also annexed,

ELEMENTS OF PLAIN and SPHERICAL TRIGONOMETRY.

E DIN BURGH

E

Printed for J. Nourse, London, and J. BALFOUR, Edinburgh,

M,DCCLXXV.