ClipArt ETC
"Consists of a coil of wire wound in two broad grooves plowed on opposite sides of an iron cylinder." — Avery, 1895

Siemens armature

"Consists of a coil of wire wound in two broad grooves plowed on opposite sides of an iron cylinder."…

"In order to make the winding and connections clear, one coil and the commutator is shown assembled, although the latter is not put in place until after all the sections have been wound, the ends of the wires being temporarily twisted together until all can be soldered to the risers." — Hawkins, 1917

Siemens' drum winding

"In order to make the winding and connections clear, one coil and the commutator is shown assembled,…

F, fixed coil; D, movable coil; S, spiral spring; T, Torsion head; MM, Mercury cups; I, Index needle.

Siemens Electrodynamometer

F, fixed coil; D, movable coil; S, spiral spring; T, Torsion head; MM, Mercury cups; I, Index needle.

"Illustrating the principle of Siemens' drum winding. In order to make the winding and connections clear, one coil and the commutator is shown assumbled, although the latter is not put in place until after all the sections have been wound, the ends of the wires temporarily twisted together until all can be soldered to the risers. the cores of these early machines were of wood, overspun circumferentially with iron wire before receiving the longitudinal copper windings." -Hawkins, 1917

Siemens' Drum Winding

"Illustrating the principle of Siemens' drum winding. In order to make the winding and connections clear,…

The inventor of the telegraph that used a needle to point to the right letter instead of using Morse code.

Ernst Siemens

The inventor of the telegraph that used a needle to point to the right letter instead of using Morse…