' Understanding About Electricity:
The Mastery of Power' by C. L. Boltz
A man can lift nearly a hundred pounds while the motor of an electric crane can deal with a hundred tons. Both electric motors and generators depend on the principles of electricity laid down by Ampere and Faraday a hundred years ago. But despite the complexity of modern equipment these principles can be illustrated, as C. L. Boltz explains, with a nail, a piece of wire, and a battery.
