If we are looking at books about London stations, John Betjeman's "London's Historic Railway Stations" is more of a good (fascinating) and learned read than a straightforward history. He teamed up with John Gay who took a string of very charismatic photographs. If you like Betjeman's witty but informed style, it's one of his best. Obviously concentrates on the architecture. A chapter on each terminus in turn, apart from the "new" Euston (it was then), which he airily dismisses in a few lines!