The history of reference publishing has fascinated me, not just because of my own work in the field, but because of the characters who have inhabited that world. Building an authoritative reference work on a subject is a massive task which requires an editor to approach his field of study with obsessive zeal. Take for example the Oxford English Dictionary, which not only provides definitons for words but detailed etymologies and historical citations for each word's usage.
Simon Winchester has written a fascinating book on how the OED came into existence, under the guidance of Scottish lexicographer James Murray. He solicited the help of volunteers across the world for his massive undertaking, and one of the biggest contributors was a mysterious man named William Minor. Wikipedia offers this description:
[Minor] proved to be one of the most effective of the volunteers, systematically reading through his library, and compiling lists of the occurrence of words. These he kept current with the words needed in the volume being worked on at the time. As his lists grew, he was able to supply quotations on demand for a particular word.The quantity and quality of Minor's work was so substantial that Murray felt compelled to go see the man in person. He traveled to London, only then to discover that Minor was not a professor or a bookseller, but rather an inmate at the Broadmoor Criminal Lunatic Asylum.
Winchester's book, called The Professor and the Madman, is a fascinating story, even if you're not particularly interested in the history of dictionaries.