Sir Walter Scott, weighs 115 tons, is 110 feet (34 m) long and has a 19 feet (5.8 m) beam. Built at Dumbarton in 1899 It is powered by its original three-cylinder triple expansion steam engine and has two locomotive-type boilers] which until the end of 2007 were fired by solid fuel fed into the firebox by a stoker. At a time when most steamers changed to oil-fired boilers, the Sir Walter Scott kept using solid fuel to meet the requirement of ensuring that Glasgow's water supply is not polluted, changing from coal to coke to reduce air pollution. In a refit at the end of the 2007 season the boilers were altered to run on biofuel. During this refit, the superstructure was rebuilt and a forward deck cabin was added. The vessel has a crew of five