OCR Text |
Show G8 GLOSSARV. Spain, and other countries. Elym., dun or dune is an AngloSaxon word for hill. EARTH's CRusT. Such superficial parts of our planet as are acces~:~ ible to human observation. ELYTRA. The wing-sheaths, or upper crustaceous membraneR, which form the superior wings in the tribe of beetles, being crustacemts appendages which cover the body and protect the true membranous wing. Etym., eXvrpoJ', elytron, a sheath. EocENE. See explanation of this word, vol. iii. p. 55. EscARPMENT, the abrupt face of a ridge of high land. Elym., cscarper, French, to cut steep. EsTUARIES· Inlets of the land, which are entered both by rivers and the tides of the sea. Thus we have the estuaries of the Thames, Severn, Tay, &c. Etym. JEstus, the tide. FALlJNS. A provincial name for some tertiary strata abounding in shells in Touraine, which resemble in lithological characters the ' crag' of Norfolk and Suffolk. FAULT, in the language of miners, is the sudden interruption of the continuity of strata in the same plane, accompanie<l by a crack or fissure varying in width from a mere line to several feet, which is generally filled with broken stone, clay, &c., and such a displacement that the separated portions of the once continuous strata occupy different levels. No. 92. The strata a, b, c, &c., must at one time have been continuous, hut a fracture having taken place at the fault F, either by the upheaving of the portion A, or the A n sinking of tl1e portion B, the strata were so displaced, that the bed a in D is many feet lower than the same bed a in the portion A. FAUNA. The various kinds of animals peculiar to a country constitute its FAUNA, as the various kinds of plants constitute its FLoRA. The term is derived from tl1e FAUNI, or rural deities in Roman Mythology. FELSPAR. A simple mineral, which constitutes the chief material of many of the unstratified or igneous rocks. The white angular portions in granite arc felspar. It is originally n. German miners' term. Etym., feld, field, and spalh, a very old minera- OLOSSARY. 69 logical wortl in Germany, which seems to have been at first specially avplie<l to a transparent kind of gypsum calltd selenite. FELSPATHIC, Of or belonging to felspar. FERRUGINOus. Anything containing iron. Etym., ferrum., iron. FLOETZ RocKs.. A German term applied to the secondary strata by the geologists of that country, because these rocka were sup} J~.sed to occur most frequently in flat horizontal heels. Etym., jlotz, a layer or stratum ; the word is npplied in some parts of Germany to pavements and plastered floors. FLORA. '~he various kinds of trees and plants found in any country constitute the Flora of that country in the language of botanists. FrJuvrATII.E. Belonging to a river. Etym.,jluvius, a river. FoRMATION. ~ group, whether of alluvial deposits, sedimentary strata, or I~neous rocks, referred to a common origin or period. FossiL. All mmerals used to be called fossils, but geologists now use the w~rd ~nly to express the remains of animals and plants found buned m the earth. Etym., fossilis, anything that may be dug out of the earth. GALENA, a metallic ore, a compound of lead and sulphur. It has often the appearance of highly polished lead. Elym., yaXew, galeo to shine. GARN~T. A simple mineral generally of a deep red colour, crystallized, most commonly met with in mica slate, but also in granite and other igneous rocks. GAULT. A provincial name in the east of England for a series of beds of clay and marl, the geological position of which is between the upper and the lower greensand. See Table II. F, p. 390. GEOLOGY, GEOGNOSY. Both mean the same thing, but with an unnecessary degree of refinement in terms, it has been proposed to call our description of the structure of the earth geognosy. (Etym. yw, gea, earth, and ytvwuKw, ginosco, to know,) and our theoretical speculations as to its formation geology. (Elym., yEct, and Xoyoc, logos, a discourse. GLACIER. The vast accumulations of ice and hardened snow in the Alps and other lofty mountains. Etyrn, glace, French for ice. GLACis. A term borrowed from the language of fortification, where it means an easy insensible slope or declivity, less steep than a talus, which see. VNEiss. A stratified primary rock, composed of the same materials as granite, but having usually a larger proportion of mien, and a lamin(\ted texture. The wor~l is a German min~r's term, |