The Morse telegraph sounder (Fig. 61) consists of an electromagnet and a soft-iron armature.

A piece of brass wire, O, is soldered to the diaphragm disk B and the soft-iron armature H, to connect them solidly.

He took a long piece of soft-iron wire and fed it into the hollow of the first magnet.

Of course you are aware that it is the electrons within the soft-iron core of the electro-magnet who produce the magnetic effect.