Electricity Meter (1888) | Shallenberger's meter supplies AC power

 "Faith is like electricity. You can't see it, but you can see the light" Unknown author, Poor Man's College

In the late nineteenth century, George Westinghouse was a happy man. He had just demonstrated that an alternating current (AC) generator could be used to power lights a mile away. It now dawned on him that he could make a fortune charging for AC electricity. All he needed was an electricity meter based on an alternating current. Thomas Edison was also fairly content because his company, General Electric, was generating the more popular direct current (DC) electricity and he was charging by the lamp.

This Edison electrolyte meter from circa 1881 uses electrolysis to
 measure the consumption of electricity

Oliver Shallenberger (1860-1898), a graduate of the US Naval Academy, had been watching the developments in AC generation closely and had been working on an AC electrical meter. He had taken his early ideas to Thomas Edison, but as the meter was not DC related, Edison was not interested. Shallenberger then visited Westinghouse to present his ideas.

Westinghouse was baffled by Shallenberger's drawing, but after half an hour gave him the job of chief electrician at his company. So it was that Shallenberger left the Navy in 1884 and joined the Westinghouse Company.

                             

In 1888, Shallenberger was working on a new AC lamp when a spring fell out and landed on the inside ledge of the lamp. He noticed that the spring was moving under the force of the nearby electric fields. He took this idea for his electricity meter, which became the industrial standard. The design was very similar to that of a gas meter. The same basic meter technology is still used today. Nikola Tesla later showed that Shallenberge's meter was actually a type of AC electrical motor.