CHAPTER XXXIX.

=THE MECHANICAL POWERS.=

=Power= 405

=Lever= 405

The principles of 405

Wheels and pulleys considered as levers 405, 406

Power transmitted by gear wheels and pulleys combined 407

=Horse Power= 407

Calculating the horse power of an engine 407

Testing the horse power of an engine 408

=Safety Valve Calculations= 409

=Heat= 410

Latent heat 410

=Water= 410

=Steam= 410

Saturated 410

Superheated 410

Expansion of 411

Absolute pressure of 411

Weight of 411

Volume and pressure of 411

=Heat= 411

Conversion of heat into work 411

Joule's equivalent 411

Mechanical equivalent of heat 411

Mariotte's law 411

Radiation of heat 412

Conduction of heat 412

Convection of heat 412

Modern Machine-Shop Practice, Volumes I and II · 第 26 / 49 章