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cam, mechanical device
(Encyclopedia)cam, mechanical device for converting a rotating motion into a reciprocating, or back-and-forth, motion, or for changing a simple motion into a complex one. A simple form of cam is a circular disk set...rivet
(Encyclopedia)rivet, headed metal pin or bolt whose shaft is passed through holes in two or more pieces of metal, wood, plastic, or other material in order to unite them by forming the plain end into a second head....almond
(Encyclopedia)almond, name for a small tree (Prunus amygdalus) of the family Rosaceae (rose family) and for the nutlike, edible seed of its drupe fruit. The “nuts” of sweet-almond varieties are eaten raw or roa...surveying
(Encyclopedia)surveying, method of determining accurately points and lines of direction (bearings) on the earth's surface and preparing from them maps or plans. Boundaries, areas, elevations, construction lines, an...Leyden jar
(Encyclopedia)Leyden jar līˈdən [key], form of capacitor invented at the Univ. of Leiden in the 18th cent. It consists of a narrow-necked glass jar coated over part of its inner and outer surfaces with conductiv...Pomo
(Encyclopedia)Pomo, Native Americans of N California, belonging to the Hokan branch of the Hokan-Siouan linguistic stock (see Native American languages). The Pomo were the most southerly Native Americans on the Cal...night blindness
(Encyclopedia)night blindness, inability to see normally in subdued light. It is usually a result of vitamin A deficiency. The rod cells, one of two light-sensitive areas of the retina of the eye, are impaired in t...eccentric
(Encyclopedia)eccentric, in mechanics, device for changing rotary to back-and-forth motion. A disk is mounted off center on a shaft. One flat, open, circular end of a rod fits around the edge of the disk; the other...Young's modulus
(Encyclopedia)Young's modulus [for Thomas Young], number representing (in pounds per square inch or dynes per square centimeter) the ratio of stress to strain for a wire or bar of a given substance. According to Ho...pencil
(Encyclopedia)pencil, pointed implement used in writing or drawing to apply graphite or a similar colored solid to any surface, especially paper. From prehistoric times lumps of colored earth or chalk were used as ...Browse by Subject
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