With the page turned vertically, there are two river views here. The top one shows what may be a large ceremonial barge on the River Thames, possibly with All Saints Church, Isleworth, in the distance on the left; compare folios 46 verso and 47 recto (D18651, D18652). The notes above presumably relate to heraldry, flags and perhaps uniforms associated with the vessel. Compare the slight outline of a barge on folio 71 verso opposite (D18679) and see under folio 4 recto (D18600) for further discussion.
Apparently in relation to the lower view, both Finberg and Turner scholar C.F. Bell suggested in undated notes that the subject is ‘Garrick’s Temple at Twickenham’,1 meaning the eighteenth-century actor David Garrick’s Temple to Shakespeare in the riverside grounds of his house at Hampton. See the entry for a watercolour study of the site, Tate D25145 (Turner Bequest CCLXIII 23) and drawings in the 1827 Isle of Wight sketchbook (Tate D20762, D20764; Turner Bequest CCXXVII 20, 21); however, that building is more substantial, with a dome and a pedimented portico.
The structure here bears more resemblance to the rotunda of the Pavilion at the corner of Syon Park, down-river of Isleworth (see folio 47 recto; D18652), but there appears to be a bridge in the distance on the left here; Richmond Bridge, the next crossing upstream, is not visible from the Pavilion, so the building may have been another gazebo or boathouse in the area. What may be the same boat, with its slender mast, as seen in the upper sketch seems to be on the left here, with several figures on the near bank.
Undated MS notes by Finberg (died 1939) C.F. Bell (died 1966) in copies of Finberg 1909, Tate Britain Prints and Drawings Room, vol.II, p.647.