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DictionarySeedog whistleGalton Whistle
Galton whistle[′gȯl·tən ‚wis·əl] (engineering acoustics) A short cylindrical pipe with an annular nozzle, which is set into resonant vibration in order to generate ultrasonic sound waves. Galton Whistle an acoustic radiator of the jet type in the frequency range from 2-3 to 40-50 kilohertz. The action of the Galton whistle is based on the excitation of vibrations in a hollow cylinder, or resonator, by a stream of air flowing from a ring-shaped slot and impinging upon the sharp edge of the cylinder. Periodic eddies develop at the sharp edge and excite vibrations in the resonator’s air volume. The radiation frequency of the whistle depends upon the depth of the resonator (adjustable with a micrometer screw) and the air pressure. The Galton whistle was the first ultrasonic source. It was proposed by the English scientist F. Galton in 1883. REFERENCEBergman, L. Ul’trazvuk i ego primenenie v nauke i tekhnike, 2nd ed. Moscow, 1957. (Translated from German.).Galton whistle
Gal·ton whis·tle (gahl'tŏn), a cylindrical whistle, attached to a compressible bulb, with a screw attachment that changes the frequency; used before audiometers to test the hearing.Gal·ton whis·tle (gawl'tŏn wis'ĕl) A cylindric whistle, attached to a compressible bulb, with a screw attachment that changes the frequency; used to test hearing. Galton whistle (galt′ŏn) [Sir Francis Galton, Brit. scientist, 1822–1911] A whistle used to test hearing.Galton, Sir Francis, English explorer and anthropologist, 1822-1911. Galton delta - a more or less well-marked triangle in a fingerprint; in dermatoglyphics, the figure at the base of each finger in the palm.Synonym(s): triradiusGalton law of regression - average parents tend to produce average offspring, but children of extreme parents inherit parental peculiarities to a lesser degree than they appear in the parentsSynonym(s): law of regression of meanGalton system of classification of fingerprints - a system of classification based on the variations in the patterns of the ridges, which are grouped into arches, loops, and whorls.Galton whistle - a cylindrical whistle attached to a compressible bulb used to test hearing.ThesaurusSeeSir Francis Galton |