The first drawing may be a drapery study for one of the officers on the left hand side of West's painting The Death of Major Peirson, 1783, (Tate Britain). France invaded Jersey on 5 January 1781. The governor surrendered the island after the fall of its capital, St Helier. A 24 year old garrison commander, Major Peirson, rejected the surrender and led a successful counter-attack. Peirson was in fact killed shortly before the battle, but Copley shows him dying at the moment of British victory, beneath the Union flag. The officers in the painting were said to be portraits, as was the image of Peirson's black servant, who is avenging his masters death. Peirson became a national hero and the painting drew crowds when it was first exhibited.
The second drawing appears to be for an uncompleted picture of the late 1790s and relates to completed works such as Abraham offering up Isaac and Saul reproved by Samuel.