Rotating Multiplication Table

This device is a rotating multiplication table. It consists of a wooden box containing a cylinder of sheet steel, which is rotated by turning a metal knob on the left side. A lid at the front of the box opens to reveal rows of numbers on a paper table pasted to the cylinder, and a paper strip with three horizontal rows of numbers pasted to the box in front of the cylinder. The numbers are handwritten in pen.
The leftmost numbers on the cylinder, indicated in red, increase from 1 to 75 as a knob on the side is rotated. The numbers in the top row, also indicated in red, increase from .05 5/11 to .35. From .05 5/11 through .10, these numbers increase by about .018 from one column to the next (each number at the head of a column is .01 9/11 larger than the previous one. Thus the second column has the heading .07 3/11), and from .10 through .35 they increase by .0125. The three rows of numbers on the sheet attached to the box are labeled 1/1, 1/2, and 1/4. Entries in the table are in black ink, and represent the product of the number in the uppermost row by that in the leftmost column, rounded off to the nearest hundredth (e.g., to cents). What the numbers in the table signify is unclear.
The instrument was collected in 1966 from Howard S. Pellatt, President of Dudley Shuttles. Dudley Shuttles was the descendent of a firm founded in 1825 in Wilkinsonville, Massachusetts, that made wooden shuttles for textile mills.
Compare 389100.
Currently not on view
Physical Description
wood (overall material)
paper (overall material)
metal (overall material)
overall: 14.5 cm x 37 cm x 14.5 cm; 5 23/32 in x 14 9/16 in x 5 23/32 in
ID Number
accession number
catalog number
Credit Line
Gift of. Howard S. Pellatt
See more items in
Medicine and Science: Mathematics
Science & Mathematics
Mathematical Charts and Tables
Data Source
National Museum of American History


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