Nearly two decades ago the Science Museum in London celebrated Charles Babbage’s 200th birthday – December 26, 1991 – by constructing a working version of the mathematician’s Second Difference Engine. He had designed it in 1847 to calculate and print mathematical tables. The 1991 attempt was the first to build this, or any other of Babbage’s Engines.

The completed Engine in its case was over 8 feet tall with a footprint of 12.65 feet by 6.65 feet. It weighed 5,860 pounds.

Another truly wonderful thing the builders did was prepare an Instruction Manual to Operate and Maintain Charles Babbage’s 2d Difference Engine. Can you imagine? As science fictional as it sounds, the whole thing is in earnest.

One segment particularly caught my eye.

Steady turning of the handle is required at a speed of approximately 8 to 10 calculations per minute (or 30 to 40 revolutions of the handle per minute). Slower or faster speeds will result in the Engine jamming.

This old fanzine fan realized that if Mr. Babbage and Mr. Gestetner had ever met, they’d have had something to talk about.

[Via James Hay.]