Scale: 1:12. A contemporary full hull working model of a 35-foot launch as proposed by McEwan in 1863. The hull is carved from a solid block of wood and is painted black on the upper works and interior, and white along and below the waterline. It is fitted with a single screw, which is propelled by a crank mechanism worked by 12 oarsmen pulling on double banked wooden bars. At this scale, the model represents a vessel measuring 34 feet in length by 9 feet in the beam.