Smoke Generator M2 50-Gallon

Mechanical Smoke Generator M2 (50-Gallon), one of Tuany usai to screen a heavy ponton bridge over the Rhine River, Germany. 

While smoke screens on land and sea were not new at the time of World War II, air screens were an innovation. Such screens, or curtains as they were frequently called, were set up by low-flying airplanes spraying liquid smoke-producing chemicals into the air. As the droplets floated to earth they reacted with moisture in the atmosphere and formed white smoke that hung suspended in the sky like a high, wide curtain. 

The CWS began work on air smoke back in World War I when the Army considered smoke signals as a possible means of communication between planes or between planes and the ground. The service experimented with the idea, dropped it after the armistice, and then took it 

Early devices injected liquid smoke agents into the exhaust of the plane. These soon gave way to simple spray tanks that emptied their contents directly into the air. The development of smoke tanks then received impetus from the fact that they could also be used to spray liquid toxic agents, such as mustard, on enemy troops. In other words, the Army could employ them on defensive missions to drop air curtains, or on offensive missions to drop toxic chemicals. In World War II the Army and Navy employed tanks only for the former purpose, but they were on hand in case gas warfare broke out. 

The standard airplane spray tank was, at the time of Pearl Harbor, model MIO, holding about thirty gallons of liquid and streamlined in accordance with formulas recommended by the National Advisory Committee on Aeronautics. The CWS had begun development of this tank in 1937 at the request of the Air Corps and later, lacking time and person- 

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