Double ended Scotch boiler - from PS "Waverley"
The vessel in which it was installed was the paddle steamer ‘Waverley’. The ‘Waverley’ was built in 1947 by A and J Inglis for the London and North Eastern Railway, to replace a vessel of the same name sunk during the Second World War. This, the original boiler was converted to oil firing in 1956, and was removed in the 1970s and replaced by a boiler of a non-marine type. The original boiler was acquired by the Royal Scottish Museum. It was initially stored out of doors at the Bo’ness depot of the Scottish Railway Preservation Society, and was transferred to the SMM in the 1980s
The Scotch boiler was invented on the Clyde, probably by James Howden in the 1870s, to produce steam at relatively high pressures. The type has a series of wide flues in which the fuel is burned, with above them a set of much narrower fire-tubes, to which the flue gases are returned via a chamber at the back of the boiler. At the front end of the firetubes is a smokebox which is linked to the funnel of the vessel. In a double-ended boiler, there is a single rear chamber serving both sets of flues and firetubes. This is a good and now rare example.
This boiler complements the steam engines from the ‘Newshot’ which were fed from a pair of single-ended Scotch boilers,