Mechanical calculators that are programmable? Well... not exactly. Charles Babbage almost succeeded building one in the mid-19th century, but the models I have are far less sophisticated than his invention. Even so... a decent slide rule is "almost" programmable. Algorithms exist to perform complex computations on a CURTA. Need I say more?
| - | Model | Type | Display | Programming model | Programming features | Memory | Special functions |
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Curta II | Stepped drum | 15+8 digits | N/A | N/A | N/A | N/A |
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FACIT C1-13 | Stepped drum | 13+8 digits | N/A | N/A | N/A | N/A |
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Keuffel & Esser 68 1210 "Log Log Duplex Decitrig" | Slide rule | 12" | N/A | N/A | N/A | N/A |
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Scientific Publishing Company's "slide rule watch" | Slide rule | 2½" | N/A | N/A | N/A | N/A |
