Worker in protective clothing engaging in the "quenching of 30" diameter carburized gear, heated to 1,500 degrees Fahrenheit into an oil bath of 110 degrees Fahrenheit," ca.1950

Photograph of a worker in protective clothing engaging in the "quenching of 30" diameter carburized gear, heated to 1,500 degrees Fahrenheit into an oil bath of 110 degrees Fahrenheit," ca.1950. A man in a mask and protective garb stands at left, raising his right hand in the air as he watches a pulley drop a load of flaming material into a large vat of oil. The vat sits at right, fueled by several large pipes, and in the background, one can see several other devices beneath a wall of windows.