The Darkroom Handbook and Formulary, by Morris Germain and published by Ziff-Davis in 1940 (part of the Little Technical Library series) covers a lot of ground, much of which is useful today to film photographers.  It talks about the darkroom work space and how to organize it, various techniques and gives formulas for many film and paper developers, toners and ancillary chemicals from storied photographic companies liker Agfa, Defender, Dupont, Eastman Kodak, Gevaert (before they merged with Agfa). Highly detailed.  There are various versions of this out there but I think this one, with the dark blue hardcover binding, is elegant and will look nice on display when not in use.