Then seating himself before it, you would have observed him intently research the different lines and shadings which there satisfied his eye and with sluggish but constant pencil trace further courses over spaces that in advance of had been blank. While consequently used, the heavy pewter lamp suspended in chains above his head, regularly rocked with the movement of the ship, and for ever threw shifting gleams and shadows of strains upon his wrinkled brow, till it virtually seemed that even tho...