The slide rule was used for over 400 years as a calculating/estimation tool. Abandoned with the adve
看更多 »Ace Hoffman
Fidget Spinners Galore!
These delightful animations will keep you distracted for hours! They never wear out, they never brea
看更多 »Revitavet Infrared Therapy Protocols
A guide to the use of the RevitaVet infrared therapy device for horses. This guide gives the protoco
看更多 »Pavlov's Dog
This program can be used to train behavioral scientists in basic research methods and analysis of da
看更多 »Animated Antique Posographe
The Kaufmann Posographe is a fascinating mechanical contraption which was used by photographers in t
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