Theory of Heat

CHAPTER XIII.

ON FREE EXPANSION.

Theory of a fluid rushing through a porous plug . . . 189
Determination of the mechanical equivalent of heat original: "Dynamical Equivalent of Heat" . . . 191
Determination of the absolute scale of temperature . . . 193

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CHAPTER XIV.

DETERMINATION OF HEIGHTS BY THE BAROMETER.

Principle of the barometer . . . . . 197
The barometer in a diving bell . . . . . 198
Height of the "homogeneous atmosphere" A theoretical model where the atmosphere is assumed to have uniform density throughout its height. . . . . 200
Height of a mountain found by the barometer . . . 201

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CHAPTER XV.

ON THE PROPAGATION OF WAVES OF LONGITUDINAL DISTURBANCE.

Waves of permanent type . . . . . . 203
Velocity of sound . . . . . . . 208

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CHAPTER XVI.

ON RADIATION.

Definition of radiation . . . . . . 210
Interference The phenomenon where two waves superimpose to form a resultant wave of greater, lower, or the same amplitude. . . . . . . . 214
Different kinds of radiation . . . . . 217
Prevost's theory of exchanges The principle that all bodies radiate energy regardless of the temperature of their surroundings. . . . . . 220
Rate of cooling . . . . . . . 226
Effects of radiation on thermometers . . . . 228