Eight separate sketches of the submarine 'B1' - bult in 1904 and broken up in 1922 - in the act of surfacing and submerging in 1915-18 in home waters, no doubt specifically to capture the precise effect at various stages. During 1915 it was decided to discontinue the use of pendant numbers on submarines (21 in the case of the 'B1') and paint the vessels name on the conning tower instead. The other vessel included here is a barque-rigged merchant vessel fitted with double topsails, and apparently at anchor. To lower left there is a slightly wooden study of a periscope.