Electromechanical Relay- American scientist Joseph Henry is often claimed to have invented the relay in 1835 in order to prove his version of the electrical telegraph, developed earlier in 1831. In 1825 William Sturgeon invented the electromagnet, with a single winding of uninsulated wire on a piece of varnished iron, which increased the magnetic force produced by electric current.

Revolver- One of the first Flintlock Revolvers was patented by Elisha Collier in 1814. The first percussion Revolver was made by Lenormand in Paris in 1820 and the first percussion Cap Revolver was invented by the Italian Francesco Antonio Broccu in 1833. He received a prize of 300 Francs for his invention; although he did not patent it, his revolver was shown to king Charles Albert of Sardinia.

Morse Code- Beginning in 1836, the American artist Samuel F. B. Morse, the American physicist Joseph Henry, Alfred Vail developed an electrical telegraph system. this system sent pulses of electric current along which which controlled by an electromagnet that was located at the receiving end of the telegraph system. A code was needed to transmit natural language using only these pulses, and the silence between them.

Circuit Breaker-Charles Grafton Page was an American electrical experimenter and inventor, physician, patent examiner, patent advocate, and professor of chemistry. Through his exploratary experiments and distinctive inventions, Page developed a deep understanding of electromegnetism. He applied this understanding in the service of the US patent office, in support of other inventors, and in persuing his own ill fated dream of electromagnetic locomotion. His work had a lasting impact on telegraphy and in the practice and politics of patenting scientific innovation.