English physicist Cecil Powell (standing, far right) & his Cosmic Ray Group outside the Physics Department building at Bristol University in 1949. Powell (1903-1969) pioneered the use of photo- graphic emulsions to record particle tracks & won the physics Nobel prize for this work in 1950. Left to right, back row: A. Gattiker, M. Cole, M. Andrews, M. Merritt, A. Cole, P. Ford, P. Dyer, J. Cowie, G. Hussey, M. Stott, W. van der Meere, M. Jones, B. Moore. Middle row: O. Lock, J. Davies, D. King, H. Heitler, S. Sorensen, I. Powell, C. Powell. Front row: T. Coor, W. Muirhead, U. Camerini, C. Franzinetti, N. Tobin, P. Fowler.