nmahmain copy 39088020680419 Purchased from the NMAH Library Endowment. How ed tech was born: Twentieth-century teaching machines-from Sidney Pressey's mechanized test-giver to B. F. Skinner's ...
To its 5,000 salesmen across the U.S., Grolier Inc., publisher of America’s oldest encyclopedia, last week handed out an odd-looking new product to sell door to door. A green, windowed, sheet-metal ...
IIIF provides researchers rich metadata and media viewing options for comparison of works across cultural heritage collections. Visit the IIIF page to learn more. This gray and silver-colored machine ...
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