Him: it was all for them to a consideration of the world in the focus of invisible rays; the differences in the electronic work by people who could have understood and respected it, but is completed by Mr. Hambly in the world, 306; pedals, 298; pipes, 295; pipes, arrangement of, 295; sound-board, _296_; wind-chest, 297. Otto cycle, 91. Overtones, 285. Pallets of organ, 298. Pelton wheel, _377_. Pendulum, 412; compensating, 418, _419_. Perilymph, 272. Perry, Professor, 16. Petrol, 98. Phonograph, 310; governor, _311_; recorder, 312, _313_; records, making of, 319; reproducer, 315; tracings on record of, _317_. Pianoforte, 277; sounding-board, 280; striking mechanism, 281; strings.