Excerpt:
This site contains HTML-versions of some original documents related to the early history of calculators.
For more information on the history of calculators, see Erez Kaplan's Calculating Machines, the pre-HP section of Dave Hicks' Museum of HP Calculators, James Redin's Vintage Calculators and Andrew Davie's Slide Rule Trading Post (and their lists of links).
If you are interested in the more recent history of computers, check out the document collections of Ed Thelen and the Computer History Museum.