About the Biorhythm Charting Service

The origins of the program that creates these biorhythm charts dates back to the early days of the minicomputer, circa 1973, when Brian Johnson ("Uncle BJ") created a Fortran program that "plotted" a biorhythm chart on fan-fold paper using a line printer attached to a Data General Nova computer running RDOS (maybe it was even DOS rev. 5). In 1976, I converted Uncle BJ's program to the C programming language running under UNIX version 6 as an exercise in learning C and UNIX-style file I/O, this time creating output on a ASR33 Teletype. Then in 1998, more than two decades later, I again used it as a learning exercise, this time creating a self-referencing CGI program that produces Portable Network Graphics (PNG) images for the world wide web.

Over the years I've lost track of Uncle BJ, and his whereabouts today are unknown. As for me, you can read more about what I do on my web site.

Tom Ferrin
February 6, 1998