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As identified by Finberg, this page displays three views of Rochester Castle from the northern bank of the River Medway, all made with the sketchbook turned vertically.1 The topmost prospect shows the spire of the Cathedral lightly indicated at left, the Castle at centre and Rochester Bridge across the right hand side. Boats dominate the foreground both on the left and on the right, suggesting links with the watercolour Rochester, on the River Medway of 1822 (Tate D18156; Turner Bequest CCVIII W).2 The watercolour was engraved by Thomas Lupton and published in 1824 (Tate impressions T06370, T04796–T04798). Its composition seems to have been explored thoroughly by Turner throughout this sketchbook. For an elaboration on this suggestion, and a list of the relevant folios, see the entry for folio 18 recto (D17394).
A second drawing demonstrates a section of the same view, observed from closer proximity. A delicately rendered sketch of the top portion of the Castle at centre is joined at left by the distant spire of the Cathedral and another distinctive roof at the edge of the page.
A third prospect describes a less distinct clutter of rooftops, presumably a collection of dwellings and riverside buildings at Rochester.
The paper here is marked with dry scratches of brown; perhaps watercolour or some other liquid substance.