the abacus and the slide rule...

[Judith Rosen <***>]

Recently I was researching the history of digital computers, which led me to look into analog computers as well. I've always considered myself "an analog girl" (preferring a complete clock-face over a digital readout and various dial controls on machines to programmable digital pushpads, etc.) so I was curious about how the notion for using a binary system came to be the accepted approach. One person I asked said it was because of the nature of electricity, which can be either on or off, so the zero represented "off" and the one represented "on". That made a bit of sense to me, but it doesn't explain the ancient use of the abacus as one of the first (known) digital computational devices. Among the nifty things I inherited from my father were his Japanese Soroban abacus and his (almost as ancient) slide rule. During my research I discovered that the slide rule is designated as an example of an analog computational device. Does anyone on the list have experience with analog computers or with hybrid computers? I hadn't realized that there are hybrid systems, but it seems to me that this would be a very good idea. Can anyone elaborate, please?

Judith
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BioTheory: An electronic journal of general science based on the Relational (Rosennean) Complexity Paradigm