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GEOGRAPHICAL DEFINITIONS.

Altitude, in geography, is employed to denote classes, great and small; the former dividing the the perpendicular height of any object, as the surface into two equal, the latter into two un altitude of a mountain is its height above a equal parts. The great circles are the meridigiven level, generally that of the sea.

ans, equator, ecliptic, and horizon ; the small Antarctic is a term applied, in opposition to circles are parallels of latitude, &c. Arctic, to the south pole, to the regions which Circles Polar are the two circles which enencompass it, and to the circle by which they compass the polar regions, and are 23} degrees are supposed to be bounded at the distance of from the poles. 23° 28' from the pole.

Climate is a term that expresses that particuAntipodes is a term applied to those inhabit- lar combination of temperature and humidity to ants of the terrestrial globe who live diametri- which any region or country is generally subcally opposite to each other. It is derived from ject ; or, in more general terms, it implies the the circumstance of their being opposed feet to actual state of the incumbent atmosphere. feet. As the antipodes are every way distant Continent is a large tract of land, containing 180° from each other, they have equal latitudes, several contiguous countries, without any sepathe one north and the other south. They have ration of its parts by the intervention of water. also the same seasons and length of day and Crater is the opening of a volcanic moun. night, but at contrary times, it being summer tain from which the smoke and ignited matter with one while it is winter with the other, and issue. day with one while it is night with the other. Current is a body of water in motion, either

Archipelago is a term applied to any part of on land or in the ocean. the sea containing numerous islands, particular- Degree is the 360th part of a circle, or the ly to that part of the Mediterranean situated 30th part of a sign. Each degree is divided into between the coast of Asia Minor and European 60 equal parts or minutes, and each minute into Turkey.

60 seconds. Basin is a term employed to denote those Degree of latitude is that part of a meridian lower tracts of the earth's surface which are included between two points at which the differwatered by large rivers, and into which the wa- ence in the elevation of any of the heavenly ters of the adjacent districts descend.

bodies, at the same instant, is equal to the 36th Bay is an arm or portion of the sea extending part of a circle. into the land ; as the Bay of Biscay.

Degree of longitude is the space between two Cape is the termination of a promontory, or meridians; that make an angle of one degree portion of land projecting into the sea or a lake; with each other at the pole. The degrees of as the Cape of Good Hope.

longitude at different latitudes are unequal, and Cardinal Points of the compass are the east, correspond to those of latitudes only at the west, north, and south points of the horizon. equator. As the meridians approach each other These divide the horizon into four equal parts till they meet at the poles, the degrees of longiof 90° each.

tude continually decrease until they become Channel is the bed of a river. It is also ap- nothing at these points; hence a degree of lonplied to an arm of the sea; as the Bristol Chan- gitude in any latitude is less than a degree on nel.

the equator. Chart is a representation of the whole or part Delta is a term frequently applied to those of the earth's surface, on a plane. The word is triangular spaces of low land between the differgenerally employed to denote maps of particular ent mouths, or near the estuaries of great riv. parts of the ocean, with the surrounding coasts, ers, which have been formed by the alluvial capes, bays, headlands, &c.

deposites of their waters. Thus the lower part Circles of the Sphere are such as are suppos- of Egypt is usually called the Delta. ed to be described either on the surface of Equator is the great circle of the spheres the earth, or on the apparent sphere of the which is everywhere equally distant from the

, heavens. They are generally divided into two poles. It is thus supposed to divide the surface of the sphere into equal hemispheres, the one the valleys consist chiefly of solid ice. On the north, and the other south. All places situated summits of the mountains they are composed of on the equator have no latitude, and the days snow. and nights are always of the same length. Gravitation is the tendency which every par. Longitude is also reckoned in degrees of the ticle of matter has to every other particle, at equator.

finite distances from each other. What is called Equinoctial is a great circle of the heavens gravitation with respect to the gravitating body, corresponding to the equator on the earth. It is called attraction, in reference to the body cuts the horizon of any place in the east and gravitated to. As all bodies, whatever may be west points; and when the sun arrives at this their nature or magnitude, are only aggregated circle, it rises and sets in these points, and the particles, gravitation takes place proportionally days and nights are then equal all over the globe. between them; and this power thus becomes the Declination is reckoned north and south from it. most universal agent of the material world. It

Equinoxes are the times when the sun enters is by it that bodies retain their forms ; that the the equinoctial points. This is about the 21st component parts of the earth, and the other of March and the 23d of September; the former planets, are not dissipated in the boundless rebeing the vernal, and the latter the autumnal gions of space ; that terrestrial bodies, when equinox.

unsupported, descend to the earth ; that the Evaporation is the conversion of water into planets and their satellites are retained in their vapor, which, by this process, is raised into the orbits ; and that the solar system itself mainatmosphere, and, by a subsequent, but partial tains its place in the universe. condensation, forms clouds. As a very consid- Harbor is a place of safety for ships. erable part of the earth's surface is covered Hemisphere is half the globe when it is supwith water, which is constantly evaporating and posed to be cut through the centre by the plane mixing with the atmosphere in the state of va- of one of its great circles. Thus the equator por, a precise determination of the rate of evap- separates the northern and southern hemisoration must be of great importance in physical pheres ; the meridian divides the eastern and geography. Accordingly, many experiments western, and the horizon the upper and lower. have been made by different philosophers to de- Horizon is the great circle of the sphere which termine this point. From these we learn, that divides its surface into the upper and lower evaporation is confined entirely to the surface hemisphere. In this sense it is called the raof the water, to which it is consequently pro- tional horizon, and its plane passes through the portional. Much more vapor, therefore, rises in centre of the earth. maritime countries, or those interspersed with Horizon sensible or visible is the small circle lakes, than in inland countries. More also rises of the sphere which bounds the observer's view, during hot weather than cold ; hence the quan- and separates the visible from the invisible part tity of evaporation depends upon the tempera-, of the globe. ture.

Island is a portion of land wholly encompassGeography is a description of the earth's sur- ed by water; as Great Britain or Ireland. face ; but the enlarged sense of the term in- 13lhmus is a narrow neck of land uniting two cludes a description, both of the inhabitants and continents, or frequently a peninsula to a contiproductions of the terrestrial globe. Mathemat- nent ; as the Isthmus of Darien. ical geography describes the figure and magni- Lake is a portion of water, either entirely tude of the earth, its diurnal and annual revolu- surrounded by land, or having no other outlet tions, the cause of day and night, the succession than a river, by which its contents are disof the seasons, the method of determining the charged. When a lake is very extensive, it positions of places on the earth's surface, and obtains the denomination of sea ; as the Caspithe comparison of linear measures, with the construction and use of maps. Physical geog- Latilude is the distance of a place from the raphy delineates the principal features in the as- equator, and is estimated in degrees, minutes, pect of nature, by which the diversified regions &c., on the arc of the meridian passing through of the globe are distinguished from each other, the place. Hence the latitude is either north and portrays their agency on its inhabitants and or south, as the place is situated on the north productions. Civil or Political geography delin- or south side of the equator. The latitude of a eates the empires, kingdoms, and states, which place is always equal to the elevation of the occupy the surface of the earth, and exhibits the pole above the horizon of that place. monuments of human industry and skill.

League is the 20th part of a degree. Glaciers is a name given to extensive fields Longitude is the distance of a place eastward of ice among the Alps. Some of them clothe or westward from the first meridian, and is measthe elevated valleys on these lofty regions, ured on an arc of the equator. It is by the while others envelope the sides and summits of combination of latitude and longitude that the the mountains ; the former are denominated situation of a place on the earth's surface is delower, and the latter upper glaciers. Those in termined. As a degree of longitude is the 360th

an Sea.

part of a circle, it is necessarily greatest at the earth's surface. This name is applied both to

, equator, and thence decreases to the poles, detached heights, and connected groups or where it is nothing.

chains of these eminences. Map is a plane figure, representing either the North is that point of the horizon which is whole or a part of the earth's surface; being a equally distant from the east and west points, projection of the different countries, seas, moun- and is diametrically opposed to the south. tains, coast, rivers, and other features of the Oasis is a term frequently applied to a fertile globe, in their relative situations and proportions, district amidst vast deserts of sand. Several of as nearly as the nature of the problem will ad- these occur in the sandy oceans of the African mit; for a globular surface cannot be correctly deserts; where the contrast was so great, as to represented on a plane. Maps are therefore induce the ancients to regard them as the Heseither general or particular, as they represent perides, or isles of the blessed. the whole or part of the earth.

Ocean is the term by which the vast mass of The object to be obtained by the construction waters covering about two thirds of the earth's of a map must determine both its kind and size. surface is designated. For the sake of perspiIf it is to be a general map, embracing a large cuity, geographers have supposed it to be dividportion of the earth's surface, the size must be ed into various parts, to which they have given large, and the projection employed such as will particular names. introduce but little alteration into the configura- Pampas is a name given by the South Ameritions of the countries it contains. Otherwise, cans to the vast plains, which characterize their the multiplicity of objects it must comprehend, country. and the alteration they would undergo, would Parallels of latitude are small circles of the render the representation altogether inadequate sphere parallel to the equator. to the purpose. If, for instance, it is intended Peninsula is any portion of land nearly surto construct a planisphere to be used in the study rounded by water. The term is generally apof astronomical geography, the stereographic plied to those parts which project into the projection on the plane of the horizon is best ocean, and are joined to the main land by an adapted. If a map of the world, for the pur- isthmus. poses of physical geography be the object, the Plateau is an elevated plain, or any high tableplane of the meridian is to be preferred, as this land terminated on all sides by declivities. The enables the geographer to present the old and central parts of Asia, the middle regions of new continents unbroken; the one being exhib- Spain, and the vast elevated lands on which ited in the eastern, and the other in the western. Mexico is situated are all of this kind. The principal aim in this choice should be to Polar circles are two small circles of the exhibit the inost faithful picture of the regions sphere which encompass the frigid zones, and to be represented, upon the largest scale which are 23° 28' distant from the poles. the size of the map will admit, and consequent- Pole is the point on the earth's surface where ly to exclude every thing foreign to the object in it is penetrated by the axis. As this axis termiview. The top of a map is considered as north, nates in two opposite points, the one is the north the bottom south, the right hand east, and the and the other the south pole, and each is 90° left hand west.

from the equator. Measure. The English statute mile consists of Prairie is a term applied to the unwooded 5,280 feet, 1,760 yards, or 8 furlongs. The Rus- tracts in the great valley of the Mississippi. sian werst is little more than of a mile English. Promontory is a portion of land projecting into The Scotch and Irish mile is about 14 English. the sea, the end of which is generally called a The Dutch, Spanish, and Polish, is about 31 cape. English. The German is more than 4 English. River is a considerable body of water collectThe Swedish, Danish, and Hungarian, is from 5 ed in the more elevated parts of the land, and to 6 English. The French common league is descending into the lower, either discharging itnear 3 English. The English marine league is self into another river or flowing into the sea. 3 English miles.

The courses of rivers always mark the greatest Meridian is a great circle, passing through the declivities of land over which they flow, and poles of the earth, and any given place on its their magnitude is generally proportional to the surface. It therefore divides this surface into height and distance of their sources. two hemispheres, the one being the eastern, and Savanna is a term by which the vast extendthe other the western. The first meridian of ed plains in America are frequently denoted. any country is that from which its geographers, Sea, in its general extent, implies the whole navigators, and astronomers commence their of that vast body of water which covers a great reckoniog of longitude.

part of the globe. It is, however, used to deMinute of a degree, is the 60th part of a de- note a particular part of this fluid, as the Baltic gree ; this is subdivided into 60 seconds, and Sea, White Sea, &c. each of these again into thirds, when necessary. Solar System is that assemblage of planets

Mountain is any considerable elevation on the and satellites which have the sun for their com

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mon centre, and which revolve about him, or plains of this kind in Europe and Asia, while rather about the centre of gravity of the system. the words savanna and pampas signify the same

Solstice is that point of time in which the sun thing in America. is at his greatest distance from the equator, or Twilight is the faint light between perfect when he is in those points of the ecliptic which day and complete night. It is occasioned by touch the tropic of Cancer and Capricorn. the atmosphere refracting the rays of the sun There are, therefore, two solstices in the year, after he has descended below the horizon. Its the one when the day is the longest, and the duration, therefore, varies not only with the latother when it is the shortest.

itude of the place, but also with the time of the Sound is a small sea so shallow that it

may be year. sounded.

Vale signifies an extent of low country lying South is one of the cardinal points of the between ranges of higher ground. Vale and compass, and that which is opposed to north. valley have distinct and appropriate meanings ;

Sphere, in geography, generally implies the the word valley is the diminutive of vale. relative positions of the equator and the horizon Volcano is a mountain which emits fire, at any point on the earth's surface. Or, as the smoke, or ignited matter. The number of achorizon varies with the position of the observer, tive volcanoes on the globe is estimated at it implies the relation of his situation with re- about 200. spect to the equator. As there can only be Wind is a current of the atmosphere. There three distinct positions of these two circles, so are three kinds of winds, permanent, periodical, there are said to be three kinds of spheres. and variable. The former blow between the When the equator and horizon intersect each tropics, and are called trade winds. Periodical other, at right angles, the position of the sphere winds, called monsoons, blow with great force is called a right sphere, which can be the case in one direction nearly half the year, and with those who live at the equator only. When towards the opposite point during the remainder. the equator coincides with the horizon, and the Variable winds blow from every point of the parallels of latitude are parallel to it, the posi- compass in the temperate regions of the globe. tion is denominated a parallel sphere. This can Year is that portion of time which the sun only take place at the poles. In all other cases, occupies in passing through the 12 signs of the the equator and horizon intersect each other zodiac, or rather, which the earth requires to obliquely, and then the position is called an ob- complete one revolution about the sun. lique sphere.

Zone is a division of the earth's surface made Steppes are plains of great extent, and wholly by two parallel circles. There are five of these destitute of the larger species of vegetables. zones, the torrid zone, the two frigid zones, and This term is generally cmployed to denote the two temperate zones.

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1. General Views of the Universe. If we look upward, we observe a blue vault stretched over our heads, which at night is illuminated by a multitude of stars. If we go to Europe, we observe the same wonderful display above us. If we travel to Arabia, or China, or the islands of the Pacific, or to the Polar regions, wherever we may go, still the sky is over us, and the sun, moon, and stars shine down upon us. The earth' is evidently swung in the air like a ball, supported by no foundation, and only kept in its place by the power of an Almighty Being

If we keep our attention fixed upon our earth and the heavenly bodies, we shall soon discover that several of them are in motion. The moon revolves around the globe. Some of

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