Firth was born in
Sheffield, the son of Thomas Firth (1789–1850), of
Pontefract, York, and Mary Loxley. He joined the
crucible steel works of Sanderson Brothers where his father worked as head
smelter, but left in 1842 to set up his own business with his brother, Thomas Jr. Their father joined them shortly afterwards, and in 1852
Thomas Firth & Sons had expanded into larger premises at the Norfolk Works in Savile Street, which had the largest
rolling mill in Sheffield. The Firth's business expanded into the armaments market, installing two large
steam hammers in 1863. In 1871, the company cast the thirty five ton "Woolwich Infant" gun. In 1875 they produced an eighty-ton gun. Firth was elected to the office of
Master Cutler in 1867, which he held for the following two years. He was elected
Mayor of Sheffield in 1874. In 1875, he presented a thirty-six acre estate to the town of Sheffield as
Firth Park. He also built a mansion for himself on the outskirts of Sheffield at Oakbrook,
Ranmoor, now part of
Notre Dame High School. In 1879, he opened
Firth College to teach arts and science subjects, which later became part of the
University of Sheffield. Firth lends his name to the Firth Wing of the
Northern General Hospital, and
Firth Court of the university. He was a
Methodist and a
Liberal. On 16 November 1880 Firth was at his Norfolk Works when he suffered a
stroke, and died 12 days later. He is buried in
Sheffield General Cemetery on Cemetery Road, where his monument is Grade II listed. ==Personal life==