In the main sketch, Old London Bridge is seen upstream to the west from the River Thames; there is a continuation at the bottom left. At the top is a separate study (or studies) made in the vicinity. Between the two registers is the torso of a man, perhaps as a detail of the figure standing in the small boat at the top right.
There is a rough stroke of yellowish watercolour at the bottom left. This may relate to the production of the 1824 watercolour known as The Port of London (Victoria and Albert Museum, London),1 engraved in 1827 as Old London Bridge and Vicinity (Tate impression: T06070); see the overall Introduction to the present Thames-related section. The view of the bridge here would have been a useful reference for the composition.
More than half the drawings in this sketchbook show the river around the bridge, and are likely to date from 1824; see the book’s Introduction.
Andrew Wilton, J.M.W. Turner: His Life and Work, Fribourg 1979, p.358 no.514, reproduced.