Part 471

Ge`o*log"ic*al*ly, adv. In a geological manner.

Ge*ol"o*gist (?), n. [Cf. F. GÈologiste.] One versed in the science of geology.

Ge*ol"o*gize (?), v. i. [imp. & p. p. Geologized (?); p. pr. & vb. n. Geologizing (?).] To study geology or make geological investigations in the field; to discourse as a geologist.

During midsummer geologized a little in Shropshire.

Darwin.

Ge*ol"o*gy (?), n.; pl. Geologies (#). [Gr. ge`a, gh^, the earth + -logy: cf. F. gÈologie.]

1. The science which treats: (a) Of the structure and mineral constitution of the globe; structural geology. (b) Of its history as regards rocks, minerals, rivers, valleys, mountains, climates, life, etc.; historical geology. (c) Of the causes and methods by which its structure, features, changes, and conditions have been produced; dynamical geology. See Chart of The Geological Series.

2. A treatise on the science.

Ge*om"a*lism (?), n. [Gr. ge`a, gh^, the earth + "omalismo`s a leveling.] (Biol.) The tendency of an organism to respond, during its growth, to the force of gravitation.

Ge"o*man`cer (?), n. One who practices, or is versed in, geomancy.

Ge"o*man`cy (?), n. [OE. geomance, geomancie, F. gÈomance, gÈomancie, LL. geomantia, fr. Gr. ge`a, gh^, the earth + mantei`a divination.] A kind of divination by means of figures or lines, formed by little dots or points, originally on the earth, and latterly on paper.

{ Ge`o*man"tic (?), Ge`o*man"tic*al (?), } a. [Cf. F. gÈomantique.] Pertaining or belonging to geomancy.

Ge*om"e*ter (?), n. [F. gÈomËtre, L. geometres, geometra, fr. Gr. gewme`trhs, fr. ge`a, gh^, the earth + me`tron measure. See Meter measure.] 1. One skilled in geometry; a geometrician; a mathematician. I. Watts.

2. (Zoˆl.) Any species of geometrid moth; a geometrid.

Ge*om"e*tral (?), a. [Cf. F. gÈomÈtral.] Pertaining to geometry. [Obs.]

{ Ge`o*met"ric (?), Ge`o*met"ric*al (?), } a. [L. geometricus; Gr. &?;: cf. F. gÈomÈtrique.] Pertaining to, or according to the rules or principles of, geometry; determined by geometry; as, a geometrical solution of a problem.

Geometric is often used, as opposed to algebraic, to include processes or solutions in which the propositions or principles of geometry are made use of rather than those of algebra.

Geometrical is often used in a limited or strictly technical sense, as opposed to mechanical; thus, a construction or solution is geometrical which can be made by ruler and compasses, i. e., by means of right lines and circles. Every construction or solution which requires any other curve, or such motion of a line or circle as would generate any other curve, is not geometrical, but mechanical. By another distinction, a geometrical solution is one obtained by the rules of geometry, or processes of analysis, and hence is exact; while a mechanical solution is one obtained by trial, by actual measurements, with instruments, etc., and is only approximate and empirical.

Geometrical curve. Same as Algebraic curve; -- so called because their different points may be constructed by the operations of elementary geometry. -- Geometric lathe, an instrument for engraving bank notes, etc., with complicated patterns of interlacing lines; -- called also cycloidal engine. -- Geometrical pace, a measure of five feet. -- Geometric pen, an instrument for drawing geometric curves, in which the movements of a pen or pencil attached to a revolving arm of adjustable length may be indefinitely varied by changing the toothed wheels which give motion to the arm. -- Geometrical plane (Persp.), the same as Ground plane . -- Geometrical progression, proportion, ratio. See under Progression, Proportion and Ratio. -- Geometrical radius, in gearing, the radius of the pitch circle of a cogwheel. Knight. -- Geometric spider (Zoˆl.), one of many species of spiders, which spin a geometrical web. They mostly belong to Epeira and allied genera, as the garden spider. See Garden spider. -- Geometric square, a portable instrument in the form of a square frame for ascertaining distances and heights by measuring angles. -- Geometrical staircase, one in which the stairs are supported by the wall at one end only. -- Geometrical tracery, in architecture and decoration, tracery arranged in geometrical figures.

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Ge`o*met"ric*al*ly (?), adv. According to the rules or laws of geometry.

Ge*om`e*tri"cian (?), n. One skilled in geometry; a geometer; a mathematician.

Ge*om"e*trid (?), a. (Zoˆl.) Pertaining or belonging to the GeometridÊ.

Ge*om"e*trid, n. (Zoˆl.) One of numerous genera and species of moths, of the family GeometridÊ; -- so called because their larvÊ (called loopers, measuring worms, spanworms, and inchworms) creep in a looping manner, as if measuring. Many of the species are injurious to agriculture, as the cankerworms.

Ge*om"e*trize (?), v. i. [imp. & p. p. Geometrized (?); p. pr. & vb. n. Geometrizing (?).] To investigate or apprehend geometrical quantities or laws; to make geometrical constructions; to proceed in accordance with the principles of geometry.

Nature geometrizeth, and observeth order in all things.

Sir T. Browne.

Ge*om"e*try (?), n.; pl. Geometries (#) [F. gÈomÈtrie, L. geometria, fr. Gr. &?;, fr. &?; to measure land; ge`a, gh^, the earth + &?; to measure. So called because one of its earliest and most important applications was to the measurement of the earth's surface. See Geometer.] 1. That branch of mathematics which investigates the relations, properties, and measurement of solids, surfaces, lines, and angles; the science which treats of the properties and relations of magnitudes; the science of the relations of space.