The North West Arm at Agatha Christie's House

These two paintings by an unknown artist are of scenes on the North West Arm in Halifax, Nova Scotia around the year 1850. The one above is labelled "Melville Island Prison, North West Arm, Halifax, Nova Scotia". The other is "The Dingle, North West Arm, Halifax, Nova Scotia, Canada". They are held by the National Trust in the UK, at Greenway, Agatha Christie's house in Brixham, Devon. Their round format makes me wonder if they were painted in England from photographs. You can view damn near every oil painting in Britain at BBC Arts/Your Paintings.