Dieselisation
Dieselisation took place largely because of the tremendous reduction in operating costs it allowed. Steam locomotives require large pools of labour to clean, load, maintain and run. They also require extensive service, coaling and watering facilities. This was their biggest inferior measure as compared to the diesel locomotive in the number of ton-miles or passenger traffic miles either could run. Diesels could and did have a significantly higher initial price per unit-horsepower delivered. However, their far greater range between fueling stops, the absence of water stops, and the much higher unit availability between inspection repair and maintenance stops, were far better than steam. Diesels simply required significantly less time and labour to operate and maintain. Diesel power was also more scalable to power requirements, owing to the control systems that allowed multiple units to be controlled by one operator. "Double header" steam power required a crew for each locomotive. Initially, diesel locomotives were less powerful than the typical steam locomotives. Between the late 1930s and the late 1950s the power available with diesel locomotive engines roughly doubled, although the most powerful steam locomotives ever built still exceeded the power of the most powerful diesel locomotives from the late Twentieth Century.
The Railway Series
The most obvious theme relating to British Railways was the decline of steam locomotion and its replacement with diesels. The first real instance of this was in the book "Duck and the Diesel Engine" (1958) in which an unpleasant diesel shunter arrives, causes trouble and is sent away. This theme may have been visited again in "The Twin Engines" (1960), in which an engine is ordered from Scotland, and two arrive, implying the other went to Sodor with his brother to avoid being scrapped. The 1963 volume "Stepney the "Bluebell" Engine" explained that steam engines were actually being scrapped to make way for these diesels, and again featured a diesel getting his comeuppance. The book "Enterprising Engines" was published in 1968, the year when steam finally disappeared from British Railways, and was the most aggressive towards dieselisation and Dr Beeching's modernisation plan. It features yet another arrogant diesel who is sent away, an additional one who stays on the Island of Sodor, a visit by the real Flying Scotsman locomotive, a steam engine, Oliver, making a daring escape to Sodor, and Sir Topham Hatt making a declaration that the steam engines of his railway will still be in service.