grav1ty, gravitee, gravitie

[Fr. grav ité; from Lat. gravitas =weight, gravity; gravis heavy: Ital. grav ità; Sp. gravidad.] I. Ordinary Language : 1. The quality or state of being heavy; weight, heavine . "A thing of that waight and gravitee, that it waieth some soules downe vnto the deepe pyt of hell."- Sir T. More: Works, p. 1,035. 2. Weight or importance; seriousne . "Length therefore is a thing which the gravitie and weight of such actions [prayer] doth require."-Hooker: Ecclesiastical Polity , bk. v. 3. Seriousne , enormity, flagrancy, atrociousne ; as, the gravity of the offense. 4. Gravene , soberne , seriousne , or dignity of demeanor. "Such ill-timed gravity , such serious folly, Might well befit the solitary student." II. Technically : Johnson: Irene , iii. 1. 1. Mus .: Lowne or depth of tone or note. 2. Physics: Terrestrial gravitation, the operation of the law of gravitation on the earth, specially in making heavy bodies fall in all parts of the planet in the direction of its center. Newton and Be el have shown that in a vacuum a sovereign and a feather will fall with equal speed, though the rate will be very different in the atmospheric air. The attraction of the whole earth, considered as a sphere, on a body at its surface, is the same as if the whole matter of the earth were collected at its center. The attraction of the earth on a body within its surface is the same as if the spherical shell situated between the body and the earth's surface was removed; or is the same as if all the matter situated nearer to the earth's surface than the body was collected at the center, and all the matter situated at a greater distance was removed. The weight of a body is proportioned to the attraction which it exerts, hence gravity in many cases means simply weight. [ Specific gravity .] (1) Center of gravity : [CENTER, III. (21).] (2) Specific gravity : Physics Min ., & c .: The relative density of a substance; the weight of a body compared with that obtain this, it is first weighed in air, which shows of another body having the same magnitudehous its absolute weight. Next it is weighed in water, to show how much it loses in this element. have now been ascertained the absolute weights of two bodies of equal bulk-viz., the one experimented on, and water, and the ratio of these weights is that also of their specific gravities. Let 1 be the weight of water, and first let the body be heavier than that liquid, then the weight which it loses in water is to the absolute weight as 1 to the specific gravity required. If lighter than water, then as the weight of the body in air, plus the weight needful to make it sink in water, is to its weight in air, so is 1 to the specific gravity. On this principle are constructed such instruments as Nicholson's portable balance. In solids and liquids the standard is generally distilled water; for the gases, atmospheric air. Specific gravity is proportionate to density, and the words may be used almost interchangeably. [DENSITY.]