File contains three copies of a photograph of Prof. H. A. Bumstead making a vacuum to split atoms at Cambridge University in the Cavendish Laboratory. A. S. MacKenzie is visible in the background, measuring a magnetic field.
File consists of a photograph of "a succession of physicists" including: Howard Bronsn, E. W. Guptill, W. J. Archibald, and J. H. L. Johnstone. The photograph was selected for inclusion in the publication "The Lives of Dalhousie University, Vol. 2" by Peter B. Waite (page 237).