Electromechanical Relay, Revolver, Morse Code, Circuit Breaker

Joseph Henry was born in New York in 1797. He became a science professor in 1826 at the age of twenty-nine. Joseph Henry invented the electrical relay. The Electrical Relay uses an electromagnet to remotely drive a mechanical or electric switch. The relay made the telegraph possible. He created a device that would eventually turn into the electric doorbell. 

Samuel Colt was born in Connecticut in 1814. Samuel Colt invented the revolver after being inspired by the action of the steering wheel on ships. The revolver is a six-shooter gun. The revolver's name comes from the rotating cylinder. The first revolvers were front-loaded with powder. Colt patented his gun and sold hundreds. When Samuel Colt died, he was one of the richest men ever.

Samuel Morse was born in Massachusetts in 1791. Samuel Morse attended Yale and became a painter. In 1825, he received a sad message that his wife died. He developed Morse code around 1830. Morse code can develop around 30 words per minute. Morse code encodes the alphabet into a series of dots and dashes, somewhat similar to braille. Radiotelegraphy used Morse code in the 1890s.

Charles Grafton Page was born in Massachusetts in 1812. He was very excited about electricity as a kid. He went to a medical school and opened up his own office. He invented the circuit breaker around 1836. The circuit breaker protects cables from short circuit damage. Page patented his 1836 invention in 1867. Thomas Edison invented a circuit breaker in 1879.