Van de Velde made a large number of drawings of parts of ships, including their sails and rigging. These provided the information he needed for his oil paintings. In this example the sail fills almost the whole sheet of paper. To the right of the sail is a rapid sketch of a ship viewed from the bow with the fore topsail shown in a similar position. A cap is the wooden block at the top of the mast through which the mast above is drawn when being stepped or lowered when being struck. The drawing is unsigned, and there is no watermark.