William Hamilton Shortt (1881–1971) was a railway engineer and noted horologist, responsible for the design of the Shortt-Synchronome free pendulum clock, a widely used time standard, employed internationally in observatories in the period between the two World Wars. His deep involvement in precision timekeeping, as a colleague of Frank Hope-Jones and director of the Synchronome Company, derived from work on the safety of train travel and the accurate measurement of train speeds, following investigations into a serious train derailment of a LSWR train at Salisbury Station in 1906, when twenty-eight people died.