This sketch has been identified as depicting the entrance to Fingal’s cave on the Isle of Staffa,1 and although the sketch is rather hastily executed it clearly depicts the basalt columns that the cave is made out of, and that Turner depicted in his watercolour Fingal’s Cave, Staffa circa 1833–4 (whereabouts unknown).2 The rapid execution of the drawing, however, makes it hard to read. Anne Lyles suggests that the sketch may ‘include the distant setting sun which forms such an important feature in the finished engraving by Edward Goodall.’3 It is hard to find the sun unless the sketchbook is held with the spine at the top, in which case it may be the circle just to the upper right of centre, framed by two vertical lines which may be the opening of the cave. This roughly matches the position of the sun in the engraving, although the sun and horizon are higher in this sketch. The present author, however, feels that the sketch is more likely to be the other way up with circles and loops at the bottom left and right representing the tops of basalt columns. If we follow David Wallace-Hadrill and Janet Carolan’s suggestion that this sketch represents Turner’s ‘first glimpse of the mouth of the cave, seen from the rocks’,4 then in this orientation it matches a view into the cave from the rocks outside the cave’s mouth, with ledges of basalt rocks at the left and right and water in the middle, and the jagged triangular shape at the top representing the narrow entrance to the cave.