70с

LORD KELVIN'S

STANDARD ELECTRIC INSTRUMENTS.

X

STANDARD DIRECT READING ELECTRIC BALANCES.

1. These instruments are founded on the mutual forces, discovered by A npere, between movable and fixed portions of an elec.ric circuit. The shape _^»©sen for the mutually-influencing portions is circular, and each such part will be called for brevity, an Ampere ring ; or sometimes simply a ring, whether it consists of only one... (More)