A Treatise of Mechanics, Theoretical, Practical, and Descriptive

A

TREATISE

OF

MECHANICS,

THEORETICAL, PRACTICAL,

AND

DESCRIPTIVE.

BY OLINTHUS GREGORY, LL.D.

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

NEWCASTLE-UPON-TYNE,

AND OF THE 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.

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