Evening Republican, Volume 21, Number 212, Rensselaer, Jasper County, 22 September 1917 — Sound Amplifier for Telephone. [ARTICLE]

Sound Amplifier for Telephone.

For the telephone user in a noisy office, a sound amplifier of compact and convenient form has been introduced, according to the Popular Mechanics Magazine. It is particularly suited for the person who receives many important toll calls, since in addition to magnifying the vibrations, it excludes foreign noises. The device consists of a small resonator to which an adjustable branched ear tube, such as is employed* with a .stethoscope, is Jttached. In use the receiver 18 laced on top of the amplifier.