But this fact that an electro-magnet would set a tuning-fork humming was new to Bell and very attractive.
He brought Bell to his house and showed him what Helmholtz had done--how he had kept tuning-forks in vibration by the power of electro-magnets, and blended the tones of several tuning-forks together to produce the complex quality of the human voice.
The electricity produced passes forward, where it works, by
electro-magnets of great size, on a system of levers and cog-wheels that transmit the movement to the axle of the screw.
The technique boosts nerve cells from an
electro-magnet coil placed against the scalp.
"I would liken London to an
electro-magnet because of Parliament, because of the financial institutions within London," he says.
He does this 'while listening to electronic pulses' and apparently spends 15 minutes a day on an
electro-magnet mat, that cost [pounds sterling]2,000 to be installed.
At one of the stores the tobacco had been hidden in a secret compartment behind a shelving unit that could only be opened using an
electro-magnet.
The teacher, a skeletal-featured man with the build of a bag of bones, demonstrated an
electro-magnet. We were mistaken to believe that such an ambitious project would be entrusted to us 12-year-olds.
Considering the lag of the proportional
electro-magnet, pressure sensor, converting time between the signals, it is time-consuming and can't meet the requirement of the system.