The allegedly forged painting is by the Norfolk School artist "Manton". Its subject is the Chirk Aqueduct near Llangollen and it is meant to be an earlier version of a painting of the same subject by "Manton", displayed in the Victoria and Albert Museum.
In the real world, the image used is a painting by watercolourist John Sell Cotman of the Norfolk School. It can, indeed, be found in the V&A collection. It was acquired in 1892 under the title "A Viaduct" but it was later misidentified as Chirk Aqueduct. The painting actually shows - and is titled - "Crambe Beck Bridge, near Kirkham, Yorkshire".
In the real world, the image used is a painting by watercolourist John Sell Cotman of the Norfolk School. It can, indeed, be found in the V&A collection. It was acquired in 1892 under the title "A Viaduct" but it was later misidentified as Chirk Aqueduct. The painting actually shows - and is titled - "Crambe Beck Bridge, near Kirkham, Yorkshire".