Sea Lion is a steam locomotive built in 1896 to supply the motive power to the Groudle Glen Railway on the Isle of Man and the locomotive still provides the main traction there today. The locomotive was built by W.G. Bagnall & Co., Stafford and delivered to the line in May of that year, providing sole motive power until joined in 1905 by sister locomotive Polar Bear. When delivered to the railway, the locomotive carried an olive green livery with vermilion and yellow lining and the name carried on the side water tank in gold leaf with blue shadowing, with distinctive round "spectacle" cab windows back and front. These were changed over to rectangular windows very early in the engine's career to improve driver visibility however. One distinctive feature was a displacement lubricator mounted