Larson Constructs the First Modern Polygraph (Great Events from History II: Science and Technology Series)
Article abstract: Larson developed the modern version of the lie detector, an instrument that revolutionized the administration of criminal justice in the United States.
Summary of Event
The first attempt to utilize a scientific instrument for the purpose of lie detection occurred in 1895. Cesare Lombroso, a celebrated Italian criminologist, published an account of several experiments he had conducted on criminal suspects whose truthfulness or deception he sought to determine by recording fluctuations in blood pressure or pulse rate when the suspects were questioned about the offense under investigation. The instrument that Lombroso used—called a “hydrosphygmograph”— had been invented and developed by other scientists for medical purposes and was not originally intended for use as an instrument for detecting deception. Essentially, the instrument consisted of a small, water-filled tank into which the subject’s hand was placed. The immersed fist was then sealed across the top of the tank by a rubber membrane. Changes in pulse pattern and blood pressure in the fist were transferred to the water, then changes in the water level were transferred to an air-filled tube leading to a revolving drum.
Although Lombroso reported successful results in his experiments, his research ended with the publication of his book in 1895; and it was not until 1915 that further experiments with blood pressure changes were...
(The entire section is 1823 words.)
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