![]() The whistle itself went through several different design changes to make its tones more precise and the Edelmann Institute, one manufacturer of Galton whistles, added a diaphragm to the device to prevent the sin of “over-blowing” (Ruckmick, 1923). The Galton whistle was manufactured with tables of vibration rates to five digits. The whistle was combined in the psychological laboratories with acoumeters, tuning forks, and other hearing instruments. Galton whistles were used in the examination of hearing in reptiles (Kuroda, 1923), insects (Wever & Bray, 1933), hedgehogs (Chang, 1936), bats (Galambos, 1941), and of course rats (Finger, 1941 Smith, 1941). Galton noted that natural selection had produced the best hearing of shrill notes in cats.Įarly comparative psychologists took the crude animal assessment techniques of Galton and refined them. He was also a fan of walking through the streets and seeing which types of dogs could hear higher pitches (small dogs were better at this than large dogs). He then would watch for the animal’s ears to prick up as an indication of hearing. Galton would go the enclosures of different animals, at the zoo, use the long stick to reach toward the animals and squeeze it to make a pitch. He attached the whistle to a long tube with a rubber squeeze ball at the other end. ![]() (Reportedly, Galton derived much pleasure from demonstrating this deficit to older people.)įrom his early tests on humans, Galton adapted his new whistle to test the hearing of various animals. He also noted that the ability to hear higher frequencies declined with age. Galton was able to determine that the normal upper limit of human hearing was about 18 kHz. Galton and subsequent researchers used these whistles to create increasingly higher frequency tones to test research subjects as well as animal abilities to hear different tones. Galton’s 1883 book Inquiries into Human Faculty and Its Development described some of the pioneering research he conducted with the whistle. ![]() The sliding plug was marked so that precise notes could be recorded in research. ![]() Along the tube a siding piece could be maneuvered up or down the tube to create different frequencies. Air would be forced through the tube, coming out at the slit as an audible tone. He ended up with a small brass tube with a slit at the end of it. Using some scientific ingenuity, he went about creating an object to produce the sound frequencies he wanted to study. He wanted to test hearing ability for higher frequencies but did not have a piece of equipment to adequately measure them. In the mid-1800s, Sir Francis Galton was presented with a dilemma. ![]()
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