Digitization of public domain ebooks at Distributed Proofreaders (DP) for Project Gutenberg (PG) involves collaboration between individuals across languages, continents, and centuries.
Mathematical publications of the late 19th and early 20th centuries were often in French or German. When I joined DP in late 2007, a number of mathematics books in both languages were in process. And among many people I had never encountered: Joshua Hutchinson had prepared for DP numerous books held by the Cornell University Historical Math Monographs collection. Laura Wisewell had scanned and prepared a few dozen volumes from the University of Glasgow mathematics library. Amy Cunningham was tireless, meticulous, and thoughtful in her dedication to DP’s process and mission. David Wilson was a primary repository of technical knowledge about all things (La)TeX, DP, and PG.
Calcul des Résidus by Ernst Lindelöf is a short book on parts of complex analysis related to residues, series representations, elementary and special functions. The book, project-managed by Joshua Hutchinson and completed in 2009, is among the first I post-processed (performed global assembly and final polishing) at DP. Everything was new: The integration of LaTeX into the DP work flow, the development of best practices, and I to the tasks of post-processing.
One interesting aspect of the story is typographical: The book uses a distinctive large operator symbol to denote a sum of residues, first introduced on page 28 (page 40 of the PDF file). Neither David Wilson nor I had seen the symbol elsewhere, and nothing in Scott Pakin’s Comprehensive Guide to LaTeX Symbols matched. With David Wilson’s mentoring and guidance, I found a prototypical copy of the symbol in the page scans and extracted it to a bitmap; used Peter Sellinger’s Potrace to convert the symbol to encapsulated postscript; and wrapped the vector glyph in a TeX box. The PG book’s LaTeX preamble contains unabridged details.
Théorie des Fonctions Elliptiques, a weighty treatise by Charles Briot and Jean Claude Bouquet, was completed in 2011. Project-managed by Laura Wisewell, and by Colin Bell after Dr. Wisewell’s untimely death in 2007, the book was an unusual, protracted, and intensive collaboration with Amy Cunningham, whose eagle-eyed proofreading caught hundreds of my manual keying errors. Ultimately, counting only my time, the book required upward of one hour per page to complete.
Particularly in 2025, both books are object lessons about human endeavor and purpose, potential and achievement; about what we choose to value and preserve, what is fragile and easily lost, and how much weight is borne on our individual and collective choices; about how with devotion, our lives and works contribute to a living tapestry of history whether or not we invoke the supernatural.