He went to Christ's on a scholarship and came top of the Natural Sciences Tripos examinations in 1883 and 1885.
He served as one of Sir J.J. Thomson's demonstrators at the Cavendish Laboratory for many years.
He also served as the Examining Chaplain to the Bishop of Salisbury, John Wordsworth between 1895 and 1911.
Fitpatrick was invited by the fellows to become President of Queens' College, Cambridge when the previous incumbent, Frederic Chase, was consecrated as Bishop of Ely in June 1906.
During his time as president, he undertook many structural improvements to the college and was a large benefactor.