William Farr (1807-1883), medical practitioner and statistician, was a friend and colleague of Florence Nightingale; they collaborated in providing statistical evidence for sanitary reform, especially in connection with the Army Sanitary Commission and the Indian Sanitary Commission. He was born in Kenley, Shropshire, on 30 November 1807 and studied medicine in Paris 1829-1831 and at University College London 1831-1832. In 1832 he passed L.S.A. and settled in London as a medical practitioner. In 1838 he was appointed to produce abstracts of data for the Registrar-General and continued to work here until his resignation and retirement in 1879. He was also a prominent figure in the Statistical Society. He died on 14 April 1879. See his entry in the Dictionary of National Biography for more details.
For information on the life and career of Florence Nightingale see the record for MSS.5471-5484, 6930 and 8991-9109.