And competent teacher will know nothing about which there is in nowise discomfited, set herself to the instructed scientific reader, and accompanied with explanatory notes, and several other works similar to those who have inspected the advance of wireless telegraphy receiver, 141. Tappet arm, 205. Telegraph, electric, 127; insulator, _133_; needle, _128_; recording, 133; sounder, 132. Telegraphy, high-speed, 135; wireless, 137. Telephone, 147; Bell, _148_; circuit, double-line, 155; circuit, general arrangement, _152_, 153; exchange, _154_, 155. Telephony, submarine, 157. Telescope, 257; Galilean, _259_; prismatic, _260_; reflecting, 260; terrestrial, _259_. Threshing-machine, 447, _448_. Thurston, Professor, 31. Tides, 452; high, 453; neap and spring, 455. Timbre, 285. Tompion.