Thomas Oswald Belshaw was born in 1853 in Brook Green, London. He was an Electrical Engineer, and elected a member of the Royal Institution.
He was initiated aged 37 in November 1889. He became Worshipful Master in 1896 and again in 1920.
Thomas succeeded his father in the Chair in 1921.
Thomas died on 6 Aug 1934 in Ravenscourt Park, aged 81.