|First Appearance||Winston's Lost Night|
|Last Appearance||Murdoch Au Naturel|
Detective Murdoch first created his own metal detector in Elementary, My Dear Murdoch. It was a hand held device based on Alexander Graham Bell’s Telephonic Probe which was created in an attempt to locate a bullet lodged in the chest of American President James Garfield in 1881.
The Detective gave his own version to Dr. Ogden, perhaps his first gift to her.
At the top of Winston’s Lost Night , Murdoch is working on his larger version of a metal detector, the Induction Balance Machine, powered by pedal work (from a stationary bicycle). It is not used in that episode, instead it comes into play three episodes later in Season 6’s Murdoch Au Naturel.
- Toward the end of the 19th century, many scientists and engineers used their growing knowledge of electrical theory in an attempt to devise a machine which would pinpoint metal, mainly for use to find ore-bearing rocks.
- Alexander Graham Bell developed one based on a hand held device by Parisian inventor Gustave Trouvé to locate a bullet lodged in the chest of American President James Garfield in 1881. His metal detector worked correctly but the attempt was unsuccessful because the metal coil spring bed Garfield was lying on confused the detector.