It was defined by Werner von Siemens as the resistance of a mercury column 1 metre long and uniform 1 mm2 cross sectional area at 0 degrees Celsius.
Siemens | Mercury Records | Mercury | Central processing unit | Law & Order: Special Victims Unit | The Unit | Mercury (planet) | Project Mercury | San Jose Mercury News | Mercury Rev | Larissa (regional unit) | Mercury (mythology) | Siemens & Halske | Economist Intelligence Unit | Diesel multiple unit | Mercury Theatre | mercury | Freddie Mercury | central processing unit | mercury (element) | Company (military unit) | UNIT | unit | Chania (regional unit) | mya (unit) | Mercury Prize | diesel multiple unit | Trikala (regional unit) | G-Unit | Air Force Outstanding Unit Award |