Page 56 – “sea-side” changed to “seaside” (study of seaside pools)
Page 136 – “sound ray” changed to “sound-ray” in Fig. 51 caption
Page 145 – “limelight” changed to “lime-light” (lime-light lantern)
Page 156 – “over-tones” changed to “overtones” (accompanied by the harmonics or overtones)
Page 162 – “key-board” changed to “keyboard” (keyboard of a piano)
Page 176 – “aërial” changed to “aerial” (stationary aerial oscillation)
Page 177 – “horse-hair” changed to “horsehair” (bow made of horsehair)
Page 274 - “Full Stop — — — — — —” changed to “Full Stop — ——— — ——— — ———”
Footnotes have been re-indexed using numbers and placed before the Index.