James Stirling (1835–1917) was a Scottish mechanical engineer. He was Locomotive Superintendent of the Glasgow and South Western Railway and later the South Eastern Railway. Stirling was born on 2 October 1835, a son^[1] of Robert Stirling, rector of Galston, East Ayrshire.^[1]

Like his brother, James Stirling favoured the domeless boiler, known as the "straightback" and cabs for the enginemen.^[2][4] Although not the first British locomotive engineer to use the 4-4-0 type, he was the first to produce a 4-4-0 which could be regarded as successful, with his G&SWR 6 Class of 1873.^[4] Stirling also invented a steam reverser, using it on most of his designs from 1874.^[2][6]

On the South Eastern Railway, Stirling designed just six classes of locomotive in his twenty years – three of these were of the 4-4-0 type for express passenger work, each more capable than the last; his other three classes were an 0-6-0 for goods, an 0-4-4T for suburban passenger, and an 0-6-0T for shunting. At his retirement at the end of 1898, the SER had 459 engines, of which 384 were to Stirling's design, and seven others had been purchased to outside design; ten more to Stirling's design would be built in 1899.^[7]

• Locomotives of the Glasgow and South Western Railway
• Locomotives of the Southern Railway