The Stewart-Warner Corp. began as the Stewart and Clark Co., founded by John Stewart, and made automotive parts, particularly speedometers.  In 1912, the Alemite Co. (led by Edgar Bassick) and the Warner Instrument Co. merged with Stewart, forming the Stewart-Warner Speedometer Corp. (later known as the Stewart-Warner Instrument Co.).  The firm had a huge factory on Diversey Parkway in Chicago. Radio production began in 1925, and to support its radio products, Stewart-Warner bought the O&T tube factory in New York City, which had previously made Silvertone tubes.  Although its tube manufacturing business was not very successful, Stewart-Warner was building radios at the rate of 1,000 units per day by 1926.  Designers included Leonard E. Parker, Sylvan Harris, and C.P. Mason.Stewart-Warner was sued by Westinghouse in 1926 over claims that Stewart-Warner sets could oscillate under certain circumstances and thereby violated patents for regenerative receivers.  Eventually all patent disputes were settled in 1927 when Stewart-Warner got a license for the RCA patent pool.  The company suffered from overproduction and had to sell off excess inventory at low prices on several occasions.  Fortunately, the company's automotive parts business did better and kept the company healthy.In addition to automotive parts, radios, and TVs, Stewart-Warner also produced refrigerators for a time.  Today, the Stewart-Warner brand continues on, with the original company now part of Maxima Technologies, a supplier of automotive parts, which is owned by Actuant Corp.  The clock tower of the original Stewart-Warner factory complex still stands on Diversey Parkway in Chicago as the only remaining monument to what was once there. Sources:1.  Alan Douglas, "Radio Manufacturers of the 1920s," Vol. 3, The Vestal Press Ltd., Vestal, NY (1991).2. Company history and current information at www.stewartwarner.com.