Artifact Details

Title

E. A. Sperry's Calculator

Catalog Number

XB97.80

Type

Physical object

Date

1911 (patented)

Manufacturer

Keuffel & Esser Company

Place Manufactured

U.S.

Identifying Numbers

Other number PAT. DEC. 26,11
Serial number S650

Dimensions

5/8 x 2 1/8 x 2 5/8 in.

Description

Two adjustable thumb wheels at top center of deivce. Lower (larger) wheel rotates the dial itself; top (smaller) wheel turns indicator needle. Center of dial reads: "Pat. Dec. 26, 11" (December 26, 1911?)

Category

Analog computer

Credit

Courtesy Gwen and Gordon Bell

Lot Number

XB97.80