Thomas Midgley Junior (May 18, 1889 – november 2, 1944) was an inventor from Ohio trained as an engineer. He developed an interest in the industrial application of chemistry. In 1921 he lead compound Tetra examined for General Motors, the substance turned out to be added to gasoline to reduce the knocking of engines.This substance was since then without restraint used, which no curiosity is because lead already in practically everything was to be found in that time, also in consumer goods. There was not yet known that many lead compounds serious nerve gifts are.