Sumlock Comptometer - Calculator Charts
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These calculator charts assisted users of Sumlock comptometers to perform calculations, particularly when dealing with Imperial units of measurement. Comptometers were mechanical devices used for calculation, often powered by a hand crank. Having tables to hand of common fractions and conversions speeded up the calculating process considerably.
Charts listed include:
This exhibit has a reference ID of CH43279. Please quote this reference ID in any communication with the Centre for Computing History.