After the war he became a research student at the Cavendish Laboratory, Cambridge University where he studied the scattering of beta particles.

In 1922, Schonland returned to South Africa and took up a post at the University of Cape Town as a lecturer and later Professor of Physics.

The South African highveld has an exceptionally high lightning incidence which provided abundant material for his work.

By 1944 he was the scientific adviser to Field Marshal Bernard Montgomery with 21st Army Group in England, France and Belgium.

In 1945, Schonland returned to South Africa at the insistence of General Jan Smuts, the Prime Minister, to establish the Council for Scientific and Industrial Research.