Works submitted in candidature by John Iball, MSc, PhD, F.Inst.P., including copies of publications dating between 1932-1938; and by Alexander McGregor BSc in 1934.
Correspondence, mostly from fellow scientists and acquaintances relating to, and often including articles of Riley's and others' research and publications. Some letters by eminent men that were bought by Riley. Many letters were packaged together and annotated by Riley when he gave them to his son for safe-keeping