It is simply a dynamo-electric machine driven by the voice of the speaker.

This is the fundamental principle of the well known dynamo-electric machine, popularly called a dynamo.

The dynamo-electric machine, according to the patent purchased by the Weldon Institute, was nearly ready.

The primary current developed by a dynamo-electric machine gives rise to secondary, tertiary, etc., currents.

In June, 1879, was published the account of the Edison dynamo-electric machine that survived in the art.

There are at present four dynamo-electric machines, but sufficient room was provided for four more.

What is a Dynamo-electric machine?