This photo is from the personal album of William Richmond Fell who commanded HM Submarine L3 on the China Station in 1928-29. He is seen here on the left, sitting on the hull of L3 with his chief engineer, Mr Waterson and Lt. Rupert Lonsdale. A similar photo, perhaps taken on the same day, shows Mr Waterson with Lt. Gordon-Duff and another officer. The future WW2 fates of Gordon-Duff and Lonsdale have been recorded and are easy to find. Waterson was perhaps older. Without knowing his first name, I've been unable to find out anything about his further career.