A text book of physics, for the use of students of science and engineering (1918)
Duncan, John, d. 1941, Starling, Sydney George, 1873- · London Macmillan · leaf 725
n the distance is greatenough, quite a large number of consecutive sounds may be repeatedby the echo. In large rooms, such as public halls, the echo may becomehighly objectionable. Even though the sounds may not be quiteseparated, the prolongation produced by the echo may lead togreat… … Fig. 643.—Acoustic lens. or refracted in a manner somewhat similar to that for light (p. 574).Thus, by constructing a lens-shaped vessel, such as an india-rubberballoon, with a gas which is denser than air (such as carbon-dioxide)the counterpart to a converging lens may be produced (p. 587). Ifthe…
Physics
Internet Archive · Gerstein Library, University of Toronto · Public Domain Mark 1.0. Free to use for anything.
