Slide rules, analyzers, and tabulators — computing before electronics
Before transistors and silicon chips, humanity computed with gears, cams, and logarithmic scales. These machines—some elegant, some enormous—solved differential equations, predicted tides, tabulated censuses, and guided bombs. Each one embodies a physical principle made tangible: logarithms etched in brass, Fourier series cranked by hand, integration performed by spinning discs. Explore six landmark analog computers that shaped the history of computation.
Handheld and tabletop devices that put mathematical power in engineers’ hands for centuries.
Lord Kelvin’s mechanical marvels that decomposed and synthesized periodic functions using gears and cranks.
Adjust amplitudes and phases of 10 tidal constituents and watch the machine superimpose harmonics into a predicted tidal curve on a scrolling paper display.
Draw or select a periodic waveform and watch mechanical sphere-and-disc integrators decompose it into Fourier components in real time.
Room-sized mechanical brains that solved differential equations and processed data at unprecedented scale.
Connect wheel-and-disc integrators to solve ordinary differential equations. Set up projectile motion or a spring-mass system and watch the mechanical integration trace a solution curve.
Punch census cards, feed them through a spring-pin reader, and watch the electrical contacts trigger counters and sorting boxes. The machine that tamed the 1890 census.
Input altitude, airspeed, and wind into the analog computer. Watch it calculate the drop angle and release point, tracing the bomb trajectory with wind correction.