GNR Express Engine 1871
Reported in both "Engineering" and "The Engineer"
The famous Stirling Single, an example of which is preserved at the National Railway Museum.
"EXPRESS LOCOMOTIVE; G. N. R.
The Great Northern Railway is so noted for its heavy and fast passenger trains that the engines employed to work those trains have a special interest for locomotive engineers. The express tralfic of the Great Northern line necessiitates the running of trains consisting of from 15 to 26 carriages from King's-cross to Peterborough at a mean speed of 47 miles per hour, these train having to be taken up gradients of 1 in 105 antl 1 in 110 throngh the Maidenlane And Copenhagen tunnels, and there being, moreover, an almost constant rising gradient of 1 in 200 to Potter's Bar, a distance of 13 miles.
Such traffic of course necessitates the employment of very powerful engines, and about two years and a half ago (vide page 331 of our sixth volume) we illustrated and described the express passenger locomotves designed by Mr.. Patrick Stirling, for working the trains then run. These engines have 7 ft. driving wheels ....
With the increase of traffic these engines have been found somewhat deficient in cylinder power, and Mr. Stirling resolved, therefore, to construct locomotives of a still more powerful class having cylinders larger than tbose of any existing passenger engines. ...
The result of this determination was the construction of an engine which during thee past eight months has run 32,000 miles with express trains and has given so much satisfaction that several more of the same class are now being built at the Company's works at Doncaster. Tbis engine has outside cylinders 18 inches in diameter with 28 in. stroke, and the driving wheels are 8 ft. 1 in. in diameter