This is a view of Cassiobury Park, near Watford, from the north-west, at Iron Bridge Lock on the Grand Union Canal. The lower lock gate is in the left foreground and the bridge (actually of brick) is to the right. Turner sketched the same scene on the verso (D12246; Turner Bequest CLV 5a), but from a few yards further back, and with a number of figures and horses in the foreground. For the canal, see note to D12241; Turner Bequest CLV 2.
The sketch is from a similar viewpoint to five sketches in the River sketchbook (Tate D06017, D06042–D06048; Turner Bequest XCVI 46, 61a–64a) which appear related to a composition study (Tate D08217; Turner Bequest CXX D) and an unfinished oil painting of Cassiobury Park, Reaping (Tate N04663),1 usually dated to around 1807. Turner also sketched the same material perhaps a little earlier, around 1804–5, in two large and detailed drawings in the Fonthill sketchbook (Tate D02215, D02227; Turner Bequest XLVII 38, 50). The present drawings appear to represent a visit separate to any of the above, when Turner was considering a composition contrasting the house with activity on the canal.
Cassiobury Park was remodeled for the 5th Earl of Essex by James Wyatt between 1799 and 1804. The house was demolished in 1927.
Martin Butlin and Evelyn Joll, The Paintings of J.M.W. Turner, revised ed., New Haven and London 1984, p.128 no.209a (pl.209).