magneto-bell

The turning of the crank of a magneto-bell rotates the armature in the magnetic field by some form of gearing at

Cyclopedia of Telephony & Telegraphy Vol. 1 A General Reference Work on Telephony, etc. etc. George Patterson 1910

_ The magneto-bell came into wide use with the spread of telephone service.

Cyclopedia of Telephony & Telegraphy Vol. 1 A General Reference Work on Telephony, etc. etc. George Patterson 1910

The alternating-current generator of the magneto-bell consists of a rotatable armature composed of a coil of insulated wire and usually a core of soft iron, its rotation taking place in a magnetic field.

Cyclopedia of Telephony & Telegraphy Vol. 1 A General Reference Work on Telephony, etc. etc. George Patterson 1910

The gravity-drop is principally adapted to the magneto-bell system of signaling, where an alternating current is sent over the line to a central office by the operation of a bell crank at the subscriber's station, this current, lasting only as long as the crank is turned, energizes the drop, which may be restored by hand or otherwise and will remain latched.

Cyclopedia of Telephony & Telegraphy Vol. 1 A General Reference Work on Telephony, etc. etc. George Patterson 1910

Electrical signals audible magneto-bell telegraph sounder telephone receiver vibrating bell visible electric lamp signal electromagnetic signal

Cyclopedia of Telephony & Telegraphy Vol. 1 A General Reference Work on Telephony, etc. etc. George Patterson 1910

a magneto-telephone as both receiver and transmitter and a magneto-bell as its signal-sending machine, as was usual in 1877, it is interesting to note that the entire motive power for signals and speech transmission was supplied by the muscular tissues of the user -- a case of working one's passage.

Cyclopedia of Telephony & Telegraphy Vol. 1 A General Reference Work on Telephony, etc. etc. George Patterson 1910