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Arm Protractor and Goniometer Invented by Samuel L. Penfield

IIIF provides researchers rich metadata and media viewing options for comparison of works across cultural heritage collections. Visit the IIIF page to learn more. It may seem obvious that surveyors, ...
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Brown & Sharpe 510 Draftsman's Protractor

IIIF provides researchers rich metadata and media viewing options for comparison of works across cultural heritage collections. Visit the IIIF page to learn more. See also ID number 1977.0460.01.