Chequers Antiques has dated this piece to the Georgian era.

Condition: Overall very good, the painting is in very good condition and has at some point in the last forty-fifty years been cleaned and relined, the frame is in reasonable condition with solid mitres and some losses to the outer edge, the painting appears clean and the colours good. The frame is probably the original.
William George Jennings was, in the words of John Constable, with whom he shared a house, described ‘Old Jennings’ as a gentleman amateur, although Constable’s confidence was greatly enhanced by Jenning’s patronage.
Jennings exhibited at the Royal Academy between 1797 and 1806, and at the Society of British Artists in 1830.
Chequers Antiques has dated this piece to the Georgian era.
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