small a scale; and some of the illustrations themselves have been supplied
by others equally applicable, more recent, and to us more familiar
examples. The first part of Chapter XI, devoted in the English edition to
English portable and fixed agricultural engines, in this edition gives
place entirely to illustrations from American practice, of steam engines as
applied to different purposes, and of appliances and machines necessary to
them. But with the exception of some of the illustrations and the
description of them, and the correction of a few typographical errors, this
edition is a faithful transcript of the latest English edition.




CONTENTS.


Classification of Engines.

Nature and uses of a Vacuum.

Velocity of falling Bodies and Momentum of moving Bodies.

Central Forces.

Centres of Gravity, Gyration, and Oscillation.

The Pendulum and Governor.

The Mechanical Powers.