Then when the next train came in and stopped, Bobbie went across the metals of the up-line and stood beside the engine. She had never been so close to an engine before. It looked much larger and harder than she had expected, and it made her feel very small indeed, and, somehow, very soft – as if she could very, very easily be hurt rather badly.

So the vast scale of the locomotive is established, as is its potentially threatening presence. The implication is that by approaching it Bobbie is approaching a sacred, inviolate place, a kind of fortress of a certain occult mystery – the mystery of the railway, a railway holy-of-holies. Furthermore, the locomotive protects its adepts, because every time Bobbie tries to attract their attention it prevents her voice from being heard:

'If you please,' said Roberta – but the engine was blowing off steam and no one heard her.
'If you please, Mr. Engineer,' she spoke a little louder, but the Engine happened to speak at the same moment, and of course Roberta's soft little voice hadn't a chance.

The places of work of other railway employees, other adepts of the railway, are also described as sacred in the book: 'that sacred inner temple behind the place where the hole is that they sell you tickets through,' 'that sacred inner temple behind the little window where the tickets are sold.' Once she is on the footplate, and the train starts off, Bobbie knows that she is in a place set apart from the mundane world, where she has no right to transgress: "'And I've no business here. I'm an engine-burglar – that's what I am,' she thought. "I shouldn't wonder if they could lock me up for this."' For Bobbie, the footplate is a strange, threatening environment – 'Her feet and legs felt the scorch of the engine fire, but her shoulders felt the wild chill rush of the air. The engine lurched and shook and rattled, and as they shot under a bridge the engine seemed to shout in her ears' – and the engine is like some kind of beast that must be tamed, yet the driver and his fireman are entirely at ease here, sitting Bobbie down and talking to her as if they were in their front room. Their kindliness and humanity reflects another aspect of the engine driver as paragon of the working class – the fact that underneath his rough outer aspect and grubby clothing he is a true gentleman (an aspect of his heroic quality). And, of course, they are proud of the craft they have mastered, showing Bobbie the functions of the various controls and responding to her questions:

'This 'ere's the automatic brake,' Bill went on, flattered by her enthusiasm. ‘You just move this 'ere little handle – do it with one finger, you can – and the train jolly soon stops. That's what they call the Power of Science in the newspapers.

The driver and his mate promise to see to the repair of the toy engine, and send Bobbie back home in the guard's van of another train – and the revelations of the sacred realm of the guard are far less momentous than those of the footplate: 'She asked the guard why his van smelt so fishy, and learned that he had to carry a lot of fish every day' – and she is later able to use her new status as an honorary adept of the sacred world of the footplate to impress her siblings, when on 'the day appointed . . . she mysteriously led them to the station at the hour of the 3.19's transit, and proudly introduced them to her friends, Bill and Jim', that is, the driver and fireman in whose world she is now something of an initiate.

The children of The Railway Children find in the railway a magical place: 'I always knew this railway was enchanted,' says Phyllis, the youngest child, at one point. It assuages their loneliness, brings them kindness and friendship, connects them to the world from which they are unwilling exiles, brings an ordering power to their lives which imprisonment and impoverishment have threatened with disorder and chaos (its recreation of order in their lives symbolized by the repair by their friends on the railway of the toy locomotive whose breakdown, on the night their father was taken away to prison, marked the beginning of their troubles). There is a threatening quality to this magic; they give certain trains names such as 'the Green Dragon', and 'the Fearsome-fly-by-night'. Yet by penetrating to the inner sanctums of the railway – the stationmaster's office, the signalbox, and most importantly the locomotive footplate, the children tame that magic and find it beneficent and kindly. The locomotive driver, Bill, is a central part of that process."