This link to the HathiTrust Digital Library opens a vast array of old railroad documents, including many prior to 1900, but with plenty of 20th Century materials too. If you're into this sort of thing, you'll lose yourself for hours here. https://www.hathitrust.org/
A 1937 list of Pullman Cars: https://babel.hathitrust.org/cgi/pt?id=mdp.39015015520508;view=1up;seq=1 July 1911 Official Guide: https://babel.hathitrust.org/cgi/pt?id=chi.19749892;view=1up;seq=7
Holy Cow! Or should I say Holy Cars? I had no idea Pullman had produced so many. I agree one could get lost in that book.
