Amplification, [182];
one stage of, [185]
Amplitude of vibration, [155]
Antenna current variation, [141]
Arlington tests, [233]
Artificial telephone line, [252]
Atom, conception of, [6];
nucleus of, [10];
neutral, [34]
Atomic number, [13]
Atoms, difference between, [12];
kinds of, [6], [10];
motion of, [35]
Attenuation of current in wires, [259]
Audibility meter, [218]