INDEX 



[The numerals refer to the pages] 



Absorption of sound, 196 



Adiabatic lines, 158 



Air-waves, general theory of, 204 



see also Sound waves 

 Amplitude, minimum audible, 167 

 Analysis of sound sensations, 2, 284 

 Anticlastic curvature of a flat bar, 152 

 Approximate solution of period- 

 equations, 83, 125, 126, 128, 256, 

 258 

 Audibility, range of frequency for, 3 



least amplitude for, 167 

 Audition, Helmholtz theory of, 289 



Bars, longitudinal vibrations, 114 

 flexural vibrations, 120, 130 



Beats, 23, 132, 138 

 relation of, to dissonance, 288 



Bells, 155 



Bessel's functions, 85, 145, 147, 259 



Blackburn's pendulum, 35 



Chain, vibrations of hanging, 84 

 Circular vibrations, 55 

 ' Circulation ' denned, 203 * 

 Clamped-free bar, transverse vibrations 



of a, 127 



Combination-tones, 181, 292, 294| 

 Communication of vibrations to a gas, 



237 



' Condensation ' defined, 160 

 Conduction of heat, effect of, on sound 



waves, 187 



' Conductivity ' of an aperture, 245 

 Conical pipe, normal modes of a, 257 

 Consonant intervals, 3, 283, 297 

 Cosine-series, 92 

 Curved shells, vibrations of, 155 

 Cylindrical vessel, normal modes of a, 



259 



Damping of vibrations, 25, 27, 57 

 effect of, on resonance, 32 

 of air- waves by viscosity, 185, 186, 



190 



of a resonator, 265 

 of an organ pipe, 269 



Degrees of freedom of a dynamical 



system, 12, 14 

 Diatonic scale, 5 



Diffraction of sound, 240, 244, 248 

 'Dilatation' defined, 107 

 Direction of sound, perception of, 



298 



Discontinuity, waves of, 181 

 Dissipation of energy by friction, 27, 



184 

 Dissipation (apparent), by generation 



of air-waves, 166, 225, 227, 232, 264, 



269 



'Divergence' defined, 199 

 Doppler's principle, 221 

 Double pendulum, 38 

 ' Double source ' of sound, 215, 226 



Elasticity, elementary theory of, 106 



coefficients of, 110, 113 



of gases, 159 

 Elliptic vibrations, 49 

 Emission of energy, by a simple source, 

 225 



by a double source, 227 



by a resonator, 265 



by an open pipe, 269 

 Energy, of a simple-harmonic vibra- 

 tion, 15 



of a string, 60 



of an elastic solid, 114 



of a bar, 123 



of a membrane, 141 



of a bent plate, 151 



of air-waves, 163, 205 

 'Extension' defined, 107 

 Extensional vibrations of a rod, 114 



of a circular ring, 136 



Finite amplitude, air-waves of, 174 

 Flexure, uniform, of a bar, 121 



of a plate, 150 

 Flexural vibrations, of a bar, 12Q 



of a ring, 136 



of a plate, 153 

 'Flux,' defined, 199 

 < Flux of energy, '165, 224 



