Large Wilson chamber completed in 1937 (Paris). It is 80 centimeters high. The coil surrounding the chamber was constructed by Cotton and Tsai to carry a heavy power load. The device has been used in the Alps every summer since 1939, at the Largentiere laboratory. The large bars, B, connect with a hydroelectric turbine and provide electrical power of 2,000 kilowatts and a magnetic field of 10,000 gauss. July 15, 1953.