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As Finberg suggests, this sketch shows the Firth of Forth from Edinburgh.1 The drawing was perhaps made from Blackford Hill (from which Turner sketched the city, see folio 46 verso; D13404; CLXV 46a) towards the Firth of Forth with the island of Inchkeith and the north shore of the Firth of Forth behind. In the middle distance are the rooftops of Edinburgh, represented with simple step-shapes, and the towering Nelson’s Monument on Calton Hill. Framing the composition on the right is Arthur’s Seat.
Finberg 1909, I, p.480, CLXV 47.