Alexander Graham Bell
Bell is also credited with the invention of an improved metal detector in 1881 that made sounds when it was near metal. The device was quickly put together in an attempt to find the bullet in the body of U.S. President James Garfield. The metal detector worked, but did not find the bullet because of the metal bedframe the President was lying on. Bell gave a full description of his experiments in a paper read before the "American Association for the Advancement of Science" in August, 1882.