It was A.O. Smith.

A.O. Smith started in Walker's Point in 1874 making bicycle parts but by the early 1900s had moved to the 30th Street Corridor manufacturing auto frames. It was a major employer and economic force here for much of the 20th century. In 1997, A.O. Smith sold its auto frame operations in the corridor to Tower Automotive. Today this vast footprint is largely abandoned and A.O. Smith is a global company with its headquarters on Milwaukee's far northwest side. After pioneering glass-coated hot water heaters in 1936, A.O. Smith now focuses on water technology.

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