Sir Isaac Lowthian Bell, 1st Baronet, FRS (18 February 1816 – 20 December 1904) was a British ironmaster and Liberal Party politician from Washington, County Durham. He was described as being "as famous in his day as Isambard Kingdom Brunel".
Bell was an energetic and skilful entrepreneur as well as an innovative metallurgist. He was involved in multiple partnerships with his brothers to make iron and alkali chemicals, and with other pioneers including Robert Stirling Newall to make steel cables. He pioneered the large-scale manufacture of aluminium at his Washington works, conducting experiments in its production, and in the production of other chemicals such as the newly discovered element thallium. He was a director of major companies including the North Eastern Railway and the Forth Bridge company, then the largest bridge project in the world.
