View this artwork by appointment, at Tate Britain's Prints and Drawings Rooms
As described by Finberg, here Turner makes three studies of the elaborate stern of a warship.1 The drawings are concentrated at right. The largest example offers a view of gun ports along a small portion of the hull. At bottom left, the lid of one of these ports is shown half-open, demonstrating the functionality of the features as well as their placement. At right, beneath the stern, Turner records the rudder head. The windows of the gallery are indicated here as well, but fully described in the other two examples. These are positioned further right, towards the edge of the paper. They both adopt a more square view of the stern, and clearly show the rudder head, although the lower rendering is more briefly realised. In the higher sketch, the ensign staff is recorded in its position atop the stern.
Finberg 1909, I, p.607.