Educational Device.
Description:
Patent for improvements in educational device by providing “a simple and comparatively inexpensive one designed for teaching addition, multiplication, subtraction, and division and capable of enabling the same to be explained with greater ease and at the expenditure of much less energy of both pupil and teacher.” (Lines 12-18) Illustration is included.
Date:
February 10, 1903
Creator:
Williams, Willoughby Columbus
Item Type:
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Patent
Partner:
UNT Libraries Government Documents Department