JOHN JACOB FOX, eldest son of Mark and Hannah Fox, was born in London on April 12, 1874, and died on November 28, 1944. He received his scientific education at the Royal College of Science, South Kensington, and at Queen Mary College, London, taking the B.Sc. degree by research in 1908 and the D.Sc. degree two years later. He was elected a fellow of the Royal Institute of Chemistry in 1916. He entered the Government service in 1896 and was appointed to the permanent staff of the Government Laboratory in 1904. He became superintending chemist in 1920, deputy Government chemist in 1929 and Government chemist in 1936.