(Encyclopedia) fluoroscopefluoroscopefl&oobreve;rˈəskōp [key], instrument consisting of an X-ray machine (see X ray) and a fluorescent screen that may be used by physicians to view the internal…
(Encyclopedia) refraction, in physics, deflection of a wave on passing obliquely from one transparent medium into a second medium in which its speed is different, as the passage of a light ray from…
(Encyclopedia) Willughby, FrancisWillughby, Franciswĭlˈəbē [key], 1635–72, English naturalist. He is known especially for his early systematic work on birds and fishes, in which he made some of the…
