W. T. Bigsby and Sons was a varnish manufacturer based in Morden Road, Mitcham. The ‘W.T.’ was William Thomas.
It is believed that he was descended from a family of brewers in Deptford. In a 1794 directory of Kent there is a Bigsby & Ritchie, jun. Brewers, Mill lane, Deptford
In 1871 he identified himself as a varnish manufacturer in Deptford at a fraud trial at the Old Bailey. His son William also appeared in this trial.
See this 20th January, 1891 article in The Manufacturer and Inventor.
In 1911 he lived at Grove Lodge, London Road. It is shown as ‘The Lodge’ on this 1910 map, just south of Mitcham Grove House. Today this is the junction of Rawnsley Avenue and London Road.
In 1911 after a fire was put out by the Mitcham Fire Brigade, the company wrote a letter to Captain Jenner.
In 1924 they made a varnish for seaplanes, see National Archives.