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NCJRS Abstract

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NCJ Number: 150443 Find in a Library
Title: United States Patent Office: Leonarde Keeler, of Berkeley, California
Journal: Polygraph  Volume:23  Issue:2  Dated:(1994)  Pages:127-133
Author(s): V Stevens
Date Published: 1994
Page Count: 7
Type: Historical Overview
Format: Article
Language: English
Country: United States of America
Annotation: This patent application was filed July 30, 1925, by Leonarde Keeler, for an apparatus for recording arterial blood pressure, known today as the polygraph.
Abstract: This invention relates to means for recording cardiac cycles and other oscillations in arterial pressure simultaneously. It can also record a respiration curve, which is recorded simultaneously with the other two curves. The patent notes that the device had been valuable in performing certain types of psychological tests based on arterial blood pressure variations. Nonetheless, the primary purpose for the invention stated in this patent application was its applications in medicine. Five figures accompany the application. 5 figures
Main Term(s): Science and Technology
Index Term(s): Courts; Criminology; History of policing; Police equipment; Polygraph techniques; Polygraphs
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