CHAPTER IV. ELEMENTARY DYNAMICAL PRINCIPLES. PAGE Measurement of Quantities . . ... . . .74 The Units of Length, Mass, and Time, and their Derived Units. 76 Measurement of Force.83 Work and Energy.87 Principle of the Conservation of Energy.92 CHAPTER V. MEASUREMENT OF INTERNAL FORCES AND THEIR EFFECTS. Longitudinal Pressure and Tension.94 Definition of a Fluid.—Hydrostatic Pressure .... 95 Work done by a Piston on a Fluid.101 Watt’s Indicator and the Indicator Diagram .... 102 Elasticity of a Fluid.. 107 CHAPTER VI. LINES OF EQUAL TEMPERATURE ON THE INDICATOR DIAGRAM. Relation between Volume, Pressure, and Temperature . . 108 Isothermal Lines of a Gas.no Isothermal Lines of a Vapour in Contact with its Liquid . . 113 Steam Line and Water Line.117 Continuity of the Liquid and Gaseous States.—Experiments of Cagniard de la Tour and Andrews.118 CHAPTER VII. ADIABATIC LINES. Properties of a Substance when heat is prevented from entering or leaving it.127 The Adiabatic Lines are Steeper than the Isothermals . .130 Diagram showing the Effects of Heat on Water.... 134
