The posting of the link http://bitsavers.org/pdf/regnecentralen/RC_4000_Reference_Manual_Jun69.pdf brought back old memories. When I moved to Aarhus University in Denmark in December 1973, I found that the Department of Chemistry where I worked had a Regnecentralen RC-4000 minicomputer with paper tape input that was used to manage the department's accounting. It had a dedicated operator who kept in running nicely until at least after I left in 1977. It had too little physical memory to be considered practical for the quantum chemistry work that I was then engaged in, and may not even have had a Fortran compiler; instead, we used the campus CDC 6400 for our research. In memory of the RC-4000, and Per Brinch Hansen's (13 Nov 1938--31-Jul-2007) many contributions to the literature of computer science, programming language design, and parallel computing, I prepared an enhancement of its manual, available here: http://www.math.utah.edu/~beebe/RC-4000/ The Web page that comes up gives a directory of the available files, and documents the steps needed to produce them. The result is a searchable document, with a single page image per PDF page, rather than the mixed bitmap scan of 1-up and 2-up pages in the original PDF file. Despite my 40+ year engagement in the TeX community, I only recently learned via the texhax mailing of some PDFTeX internals that allow one to construct a file that can retypeset n-up files into 1-up format. I therefore make this posting in the hope that someone else might be encouraged to tackle similar document improvements in the bitsavers archives. Although it takes a bit of experimentation, with the exception of the OCR conversion, the entire operation can be done with free software on pretty much any modern computing platform, thanks to the portability of the needed software. ------------------------------------------------------------------------------- - Nelson H. F. Beebe Tel: +1 801 581 5254 - - University of Utah FAX: +1 801 581 4148 - - Department of Mathematics, 110 LCB Internet e-mail: beebe(a)math.utah.edu - - 155 S 1400 E RM 233 beebe(a)acm.org beebe(a)computer.org - - Salt Lake City, UT 84112-0090, USA URL: http://www.math.utah.edu/~beebe/ - -------------------------------------------------------------------------------