IGC Has nothing on Ketland in the UK post around 1820.
Looking for UK B W entries there were none for any BJW & Co, but the following MAY be applicable:
Benjamin Walker was recorded as an action maker at 23 Steelhouse Lane from 1914 to 1916. In 1920 he was recorded at Back of 26 1/2 Whittall Street. William Walker & Son of 31 1/2 Whittall Street (1926-1929), George Walker of 95 Weaman Street and 31 1/2 Whittall Street (1930-1932) and Walker Isley & Co of 31 1/2 Whittall Street (1920-1921).
As for JT Powell, IGC has no one close to that reference I'm afraid.
Tim
