Acoustic, and Acoustical

[Gr. akoustikos.] Belonging to the ear or to sound. Acoustics, Acoustic Duct , in Anat . , a term applied to the meatus auditor i us extern us, or external pa age of the ear. Acoustics, n . pl . That branch of Physics which treats of the laws which regulate the production and propagation of the atmospheric vibrations which are perceived by the organ of hearing. In other words, it is the science of sounds, and that of the vibration of elastic bodies. See SOUND. Ac'qua, a village of Italy, province of Pisa, 16 miles S. of Leghorn, noted for warm baths. Acquac'kanonck, in New Jersey, a post township of Pa aic co., 13 miles S.W. of New York, and about 80 miles N.E. of Trenton.-A village of the same name, is situate on the Pa aic river, at the head of sloop navigation.