Toshiba's early history has two parts: One is Tanaka Seizo-sho (Tanaka Engineering Works), established in 1882, and based on a factory started by Hisashige Tanaka (1799-1881) in 1875. Eventually, under the name Shibaura Seisaku-sho ( Shibaura Engineering Works), his company became one of Japan's largest manufacturers of heavy electrical appliances. The other is Hakunetsu-sha & Co., Ltd. established as Japan's first manufacturer of light bulbs. In 1939, these two companies, leaders in their respective fields, merged to form an integrated electrical equipment manufacturer, Tokyo Shibaura Denki (Tokyo Shibaura Electric Co., Ltd.). The company soon became known as "Toshiba", which became its official name in 1978