Mirror galvanometer, [9], [42], [73]

Mirror, [47], [51]

Morse code, [35]

Motor speed, [89], [95]

driving, [91], [93], [95]

clockwork, [63]

electric, [63]

Nernst lamps, [43], [85], [98]

heater of, [99]

filament of, [99]