ов.

MECHANICS,
THEORETICHE, PRACTICAL,

OF

AND

DESCRIPTIVE.

BY OLINTHUS GREGORY, LL.D.

OF THE ROYAL MILITARY ACADEMY, WOOLWICH ;
WONORARY MEMBER OF THE PHILOSOPHICAL SOCIETIES OF LONDON AND

NEWCASTLE UPON-TYNE,

AND OF TIE NEWCASTLE ANTIQUARIAN SOCIETY.

THE THIRD EDITION,

CORRECTED AND IMPROVED,

VOL. II.

CONTAINING

REMARKS ON THE NATURE, CONSTRUCTION, AND SIMPLIFICA
TION OF MACHINERY, ON FRICTION, RIGIDITY OF CORDS,

FIRST MOVERS, &c.

AND

DESCRIPTIONS OF MANY CURIOUS AND USEFUL MACHINES.

-Talem intelligo Philosophiam naturalem, quæ non abeat in fumos
speculationum subtilium, aut sublimium; sed que efficaciter operetut,
ad sublevandi vitæ humanæ incommoda. Bacon. De Aug. Sci.

LONDON:

PRINTED FOR F. C. AND J. RIVINGTON; G. WILKIE; J. RICHARD-

SON; LACKINGTON AND CO.; G. KEARSLEY; LONGMAN, HURST,
REES, ORME, AND BROWN; J. TAYLOR; BALDWIN, CRADOCK,
AND JOY; AND WALKER AND EDWARDS.

1815.