They had humans turn the pages of intact books in scanning machines. The books mostly came from the shelves of academic libraries and were returned to the shelv

They had humans turn the pages of intact books in scanning machines. The books mostly came from the shelves of academic libraries and were returned to the shelves after scanning. You can see some incidental captures of hands/fingers in the scans on Google Books or HathiTrust (the academic home of the Google Books scans). There are some examples collected here: https://theartofgooglebooks.tumblr.com/ https://theartofgooglebooks.tumblr.com/