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ratchet and pawl

(Encyclopedia)ratchet and pawl, mechanical device that permits motion in one direction only. The ratchet is usually a wheel with slanting teeth. The pawl is a lever tangential to the wheel with one end resting on t...

Bozez and Seneh

(Encyclopedia)Bozez sēˈnə, –nĕ [key], two cliffs at the entrance to the ravine of Michmash (now the Wadi Suweinet); they are mentioned in the First Book of Samuel. ...

Louisiana State University and Agricultural and Mechanical College

(Encyclopedia)Louisiana State University and Agricultural and Mechanical College, mainly at Baton Rouge; land-grant and state supported; coeducational; chartered 1853, opened as a state seminary 1860 near Alexandri...

American Academy and Institute of Arts and Letters

(Encyclopedia)American Academy and Institute of Arts and Letters, honorary academy of notable American artists, writers, and composers. The National Institute of Arts and Letters, founded in 1898, served as the par...

Food and Drug Administration

(Encyclopedia)Food and Drug Administration (FDA), agency of the Public Health Service division of the U.S. Department of Health and Human Services. It is charged with protecting public health by ensuring that foods...

foot-and-mouth disease

(Encyclopedia)foot-and-mouth disease or hoof-and-mouth disease, highly contagious disease almost exclusive to cattle, sheep, swine, goats, and other cloven-hoofed animals. It is caused by a virus, specifically an a...

rock carvings and paintings

(Encyclopedia)rock carvings and paintings, designs inscribed on rock surfaces and huge stone monuments in many parts of the world by prehistoric or preindustrial peoples. They have been found on every continent and...

perfluoroalkyl and polyfluoroalkyl substances

(Encyclopedia)perfluoroalkyl and polyfluoroalkyl substances (PFAS), a group of several thousand synthetic organic chemical compounds made up of a chain of carbon atoms bonded to fluorine atoms. PFAS, which resist w...

monsters and imaginary beasts

(Encyclopedia)monsters and imaginary beasts. The mythologies and legends of ancient and modern cultures teem with an enormous variety of monsters and imaginary beasts. A great number of these are composites of diff...

São Tomé and Principe

(Encyclopedia)CE5 São Tomé and Principe prēnˈsēpə [key], officially Democratic Republic of São Tomé and Principe, republic (2015 est. pop. 196,000), 372 sq mi (964 sq km), W Africa, in the Gulf of Guinea...