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may 6, 1839 - Brass Instrument Psychological Test Era --} psychologist/psychiatrist use brass instrument to measure behavior * time measurement (chronoscope, chronograph, kymographs) * time production instruments (pendulums, gravity fall devices, clocwork makers, multiple interval timers) * response devices (Morse telegraphic key, lip keys, voice keys)

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Date:

may 6, 1839
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~ 187 years ago

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