Sound

action aerial agitated atmosphere audible augmented beats bell burner carbonic acid caused centre column of air condensation corresponding density direction disc distance divides echoes effect elasticity embouchure experiments fog-signal fork fundamental tone gases glass hear heard heat Helmholtz Hence hydrogen inches instrument intensity interval John Herschel law of superposition layers length light liquid longitudinal major third membrane ment miles Montlhéry motion musical sound nodal lines nodes number of vibrations observed obtained octave optical organ-pipe orifice oscillation overtones particles pass pendulum pipe pitch placed plate produced prongs puffs pulse rapidity rarefaction rate of vibration ratio reed reflected rendered resonance resultant tone rotation screen sensitive flame sonorous wave sound-wave South Foreland square stretched string surface syren temperature tion Trinity House tube tuning-fork tympanic membrane unison vein velocity of sound ventral segments vibrating segments Villejuif whistle wire