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Apparatus for Testing Errors of Refraction

Description: Patent for an eye testing device that has a movable lens, a measuring device for correction, and two different cards with test type on them which are fed into the machine during testing for astigmatism and myopia, presbyopia, and hyperopia to determine the level of correction needed in glasses.
Date: July 2, 1907
Creator: Bahn, Gustavus Adolphus
Item Type: Refine your search to only Patent
Partner: UNT Libraries Government Documents Department

Coupling-Pin.

Description: Patent for a coupling pin for railroad cars, which prevents the coupling from coming loose accidentally by having a key which locks the coupling in place and can only be undone by the cars operating systems. when it is time to disconnect the car.
Date: July 23, 1907
Creator: Yeiser, John Clarke
Item Type: Refine your search to only Patent
Partner: UNT Libraries Government Documents Department
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