An electromagnet built by Michael Faraday. It was made of an iron core surrounded by a coil of copper wire. This object only became magnetic when an electric current passed through the wire coil. Michael Faraday (September 22, 1791 - August 25, 1867) was an English chemist and physicist who contributed to the fields of electromagnetism and electrochemistry. Faraday experimented with electricity and magnetism, proposing that magnetism was a circular force. He is also known for discovering magnetic optical rotation, electromagnetic induction, inventing the dynamo, perfecting the Bunsen burner, and formulating the second law of electrolysis. Author of "Chemical Manipulation", Faraday was self-trained and contributed to the fields of electromagnetism and electrochemistry after an apprenticeship in Sir Humphrey Davy's lab. The farad (F) is named after him. As a chemist, Faraday discovered benzene, investigated the clathrate hydrate of chlorine, invented an early form of the Bunsen burner and the system of oxidation numbers, and popularized terminology such as anode, cathode, electrode, and ion. He died in 1867 at the age of 75. He had previously turned down burial in Westminster Abbey, but he has a memorial plaque there, near Isaac Newton's tomb.