Written in 1998 this book, and its sister companion 'The Darkroom Cookbook', remains a must-have for anyone interested in the alchemy of traditional photography.
The book takes you through film types, developer ingredients, types of developer and post development procedures. The difference between solvent (fine grain) and non-solvent (acutance) developers is explained and what is particularly helpful is the discussion on the effect of dilutions on developer characteristics such as speed and fine grain-ness.
Things have moved on appreciably since 1998 so some views have been overtaken by events. For example the discussion on tanning developers singles out PMK-Pyro as being the best of the bunch, but many modern-day Pyrocat users would beg to differ.
For me the significance of this book is that it gave me the confidence to mix my own developers from base materials with an understanding of what role each component of a developer plays in the developing process.
The Film Developing Cookbook by Anchell & Troop