Another toy down! This book is simply the best historical reference I've ever seen. I think it might be out of print, but places like amazon.com still seem to have it. It's nothing but a bunch of reprints, but check out what's reprinted here: On the Mathematical Powers of the Calculating Engine, C. Babbage (1837) Report of the Committee ... appointed to consider and to estimate the expense of constructing Mr. Babbage's Analytical Machine, and of printing tables by its means, C. W. Merrifield (1879) Babbage's Analytical Engine, H.P. Babbage (1910) On a Proposed Analytical Machine, P.E. Ludgate (1909) Essays on Automatics - Its Definition - Theoretical Extent of its Applications, L. Torres Y Quevedo (1914) Electromechanical Calculating Machines, L. Torres Y Quevedo (1920) Scheme of Assembly of a Machine Suitable for the Caclulations of Celestial Mechanics, L. Couffignal (1938) An Electric Tabulating System, H. Hollerith (1889) Calculating Machines: Their Principles and Evolution, L. Couffignal (1933) The Automatic Calculator IPM, H-J. Dreyey and A. Walther (1946) Method for Automatic Execution of Calculations with the aid of Computers, K. Zuse (1936) Technical Computing Machines, H. Schreyer (1939) The Outline of a Computer Development from Mechanics to Electronics, K. Zuse (1962) Proposed Automatic Calculating Machine, H.H. Aiken (1937) The Automatic Sequence Controlled Calculator, H.H. Aiken and G.M. Hopper (1946) Electronics and Computation, W.J. Eckert (1948) The IBM Card-Programmed Electronic Calculator, J.W Sheldon and L. Tatum (1951) Computer, G.R. Stibitz (1940) The Relay Interpolator, O. Cesarero (1946) The Ballistic Computer, J. Juley (1947) A Bell Telephone Laboratories' Computing Machine, F.L. Alt (1948) Binary Calculation, E.W. Phillips (1936) Computing Machine for the Solution of Large Systems of Linear Algebraic Equations, J.V. Atanasoff (1940) The Bletchley Machines, D. Michie (1972) The Use of High Speed Vacuum Tube Devices for Calculating, J.W. Mauchly (1942) The Electronic Numerical Integrator and Computer (ENIAC), H.H. Goldstine and A. Goldstine (1946) First Draft of a Report on the EDVAC, J. von Neumann (1945) Preparation of Problems for EDVAC-type Machines, J.W. Mauchly (1947) Preliminary Discussion of the Logical Design of an Electronic Computing Instrument, A.W. Burkes et al. (1946) Electronic Digital Computers, F.C. Williams and T. Kilburn (1948) The EDSAC, M.V. wilkes and W. Renwick (1949) The EDSAC Demonstration, B.H. Worsley (1949) Edited by Brain Randell, Springer-Verlag, ISBN 0-387-07114-8 -- Doug