'Some of the best physicists of the 20th century' in Cambridge, 1919.

PMS Blackett (1897-1974) produced some of the early cloud chamber photographs; PL Kapitsa (1894-1984) worked on high magnetic fields and superfluidity; P Langevin (1872-1946) established the theory of modern magnetism; E Rutherford (1871-1937) effectively founded nuclear physics with his discovery of alpha, beta and gamma rays of radiation; CTR Wilson (1869-1959) developed the cloud chamber which enabled early particle physicists to track the path of an ion.