Caledonian Railway 179 Dunalastair I Class
Design and development
McIntosh, succeeding Lambie at St Rollox in 1895, recognised that the Caledonian's growing Carlisle and Aberdeen expresses needed considerably more steam-raising capacity than existing 4-4-0s could provide. The Dunalastair I of 1896 was a 4-4-0 with what was then the largest boiler ever fitted to a British express engine — pressed at 165 psi and with a generous grate area. The result was an exceptionally free-steaming and fast engine, capable of holding 60+ mph schedules over the Caledonian's steep northern gradients.
Service and withdrawals
The 15 Dunalastair Is worked Caledonian Carlisle, Aberdeen and Edinburgh expresses from 1896. They were progressively superseded by the larger Dunalastair II (1897), III (1899), IV (1904) and McIntosh's later 4-6-0s, but lasted into LMS days. None of the Dunalastair Is were preserved.
Identification features
Inside-cylinder 4-4-0 with 6 ft 6 in coupled wheels, leading 4-wheel bogie, large parallel boiler with brass dome, distinctive Caledonian Prussian blue livery.
Notable locomotives
- 721 Dunalastair (1896, not preserved)