This is a working 3D simulation of Babbage's Difference Engine No.2 printer.
The number on the column of Figure Wheels on the right is the end result of the Difference Engine's calculations. The number is transferred by the other wheels and racks off to the printer on the left.
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The numbers are printed on the paper drum, to the left, and punched card, in the trays at the bottom. .
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A close up of the last column of figure and sector wheels.
Note, only two of the actual 30 wheels in each column are shown.
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A close up showing the horizontal racks. These are the first stage in transfering the number on the last column to the printer.
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