A simple, practical boundary between the three oceans can be obtained by prolonging the meridian of the southern extremity of each of the three southern continents to the Antarctic circle.
Where the ocean touches the continents the margin is in places deeply indented by peninsulas and islands marking off portions of the water surface which from all antiquity have been known as " seas."
Murray, " Drainage Areas of the Continents," Scot.
These " continents," " parts of the earth," or " quarters of the globe," proved to be convenient divisions; America was added as a fourth, and subsequently divided into two, while Australia on its discovery was classed sometimes as a new continent, sometimes merely as an island, sometimes compromisingly as an island-continent, according to individual opinion.
The term is so far justified in that it harmonizes better than Oceania did with the names of the other continents, and also embodies the two essential facts that it is a south-eastern extension of Asia, and that its central and most important division is the great island-continent of Australia.
The terrace closest to the land, known as the continental shelf, has an average depth of 600 ft., and connects Australia, New Guinea, and Tasmania in one unbroken sweep. Compared with other continents, the Australian continental shelf is extremely narrow, and there are points on the eastern coast where the land plunges down to oceanic depths with an abruptness rarely paralleled.
If the continuous, unbroken, horizontal extent of land in a continent is termed its trunk,' and the portions cut up by inlets or channels of the sea into islands and peninsulas the limbs, it is possible to compare the continents in an instructive manner.
(by the bull Romanus Pontifex, Dec. 20, 1584) ordered the bishops of Italy, Dalmatia and Greece to visit Rome every three years; those of France, Germany, Spain and Portugal, Belgium, Hungary, Bohemia and the British Isles every four years; those from the rest of Europe every five years; and bishops from other continents every ten years.
Possibly ridges of the sea-bed running southward from the southern continents may yet be discovered which would form more natural boundaries than the meridians.
Four great intercontinental enclosed seas are included between adjacent continents - the Arctic Sea, the Central American or West Indian Sea, the Australo-Asiatic or Malay Sea and the Mediterranean Sea.
Kriimmel has calculated the mean depth to be 2010 fathoms (12,060 ft.), while the mean elevation of the surface of the continents above sea-level is only 2300 ft.
The continental shelves include not only the oceanic border of the continents but also great areas of the enclosed seas and particularly of the fringing seas, the origin of which through secular subsidence is often very clearly apparent, as for instance in the North Sea and the tract lying off the mouth of the English Channel.
The proportions of the salts of river and sea-water are quite different, as Julius Roth shows thus: - The salts of salt lakes which have been formed in the areas of internal drainage in the hearts of the continents by the evaporation of river water are entirely different in composition from those of the sea, as the existence of the numerous natron and bitter lakes shows.
Where the trade-winds heap up the surface water against the east coasts of the continents the currents turn poleward.
The accidental use of a single name, America, for the pair of continents that has a greater extension from north to south than any other continuous land area of the globe, has had some recent justification, since the small body of geological opinion has turned in favour of the theory of the tetrahedral deformation of the earth's crust as affording explanation of the grouping of continents and oceans.
America, broadening in the north as if to span the oceans by reaching to its neighbours on the east and west, tapering between vast oceans far to the south where the nearest land is in the little-known Antarctic regions, roughly presents the triangular outline that is to be expected from tetrahedral warping; and although greatly broken in the middle, and standing with the northern and southern parts out of a meridian line, America is nevertheless the best witness among the continents of to-day to the tetrahedral theory.
There seems to be, however, not a unity but a duality in its plan of construction, for the two parts, North and South America, resemble each other not only in outline but, roughly speaking, in geological evolution also; and the resemblances thus discovered are the more remarkable when it is considered how extremely small is the probability that among all the possible combinations of ancient mountain systems, modern mountain systems and plains, two continents out of five should present so many points of correspondence.
For further treatment of the physical geography of the American continents, see North America, South America.
As discovery revealed the existence of another vast domain to the north, the name spread to the whole of the pair of continents by customary use, in spite of the protests of the Spaniards, by whom it was not officially used of North America till the 18th century.
Are to be found here and there in both continents, and nuggets were objects of worship. Tools and appliances for working metals were of the rudest kind, and if moulds for casting were employed these were broken up; at least no museum contains samples of them, and the processes are not described.
The question of the mode in which the floras of islands and of continents have been formed gave rise to important speculations by such eminent botanical travellers as Charles Darwin, Sir J.
Deperet points also that we owe to Cuvier the first clear expression of the idea of the increasing organic perfection of all forms of life from the lower to the higher horizons, and that, while he believed that extinctions were due to sudden revolutions on the surface of the earth, he also set forth the pregnant ideas that the renewals of animal life were by migration from other regions unknown, and that these migrations were favoured by alternate elevations and depressions which formed various land routes between great continents and islands.
The grandest application of analogy is that observed in the adaptations of groups of animals evolving on different continents, by which their various divisions tend to mimic those on other continents.
These widely divergent conditions give to Mexico a flora that includes the genera and species characteristic of nearly all the zones of plant life on the western continents - the tropical jungle of the humid coastal plains with its rare cabinet-woods, dye-woods, lianas and palms; the semi-tropical and temperate mountain slopes where oak forests are to be found and wheat supplants cotton and sugar-cane; and above these the region of pine forests and pasture lands.
The accurate and experienced Alexander von Humboldt considered the native Americans of both continents to be substantially similar in race-characters.
2, 22, "Round many peopled continents" for "many-peopled," ib.
Is represented in all the three great continents of the Old World, and extends as far east as Flores and Celebes, the skull is swollen and convex, the spines are cylindrical, and the tail is short and covered with spines and slender-stalked open quills.
The volume of trade is not very great, although some of the productions are exported all over Europe, and in some cases to other continents as well.
The explanation of the apparent bounding of Christianity by Europe and its offspring is not, however, to be found in any psychological peculiarity separating the European races from those of other continents, nor in any special characteristic of Christianity which fits it for European soil.
Mutatis mutandis, the same applies to Africa also, and Christianity still survives in both continents in the Coptic, Abyssinian and Armenian Churches.
The ` East appeared as the Mahommedan dominions, and beyond these the continents of Asia and Africa were so dimly discerned that little reciprocal influence was felt.
These are, briefly speaking, the decay of those great fabrics, church and empire, which ruled the middle ages both as ideas and as realities; the development of nationalities and languages; the enfeeblement of the feudal system throughout Europe; the invention and application of paper, the mariner's compass, gunpowder, and printing; the exploration of continents beyond the ocean; and the substitution of the Copernican for the Ptolemaic system of astronomy.
In order to promote the friendly understanding and co-operation of the nations on the American continents he projected a Pan-American congress, which, after being arranged for, was frustrated by his retirement.
In the case of the southern continents the difficulty is, however, to determine whether allied groups of mammals (and other animals) have reached their present isolated habitats by dispersal from the north along widely sundered longitudinal lines, or whether such a distribution implies the former existence of equatorial land-connexions.
In reality, however, it experiences fewer climatic variations than the other great continents, owing to its distance (28°) from the Antarctic circle and (11°) from the equator.
THE TROPIcAL REGI0N.The permanence of continents and great oceans was first insisted upon by J.
He systematized the form of the land within the ring of ocean - the habitable world - by recognizing two continents: Europe to the north, and Asia to the south of the midland sea.
He also pointed out reasons for accepting a division of the land into three continents - Europe, Asia and Africa.
In 1700 Guillaume Delisle published his map of the continents of the Old World; and his successor D'Anville produced his map of India in 1752.
The increasing number of measurements of the height of land in all continents and islands, and the very detailed levellings in those countries which have been thoroughly surveyed, enable the average elevation of the land above sea-level to be fairly estimated, although many vast gaps in accurate knowledge remain, and the estimate is not an exact one.
Second great series of crust waves from north to south, giving rise by their interference to six great elevated masses (the continents), arranged in three groups, each consisting of a northern and a southern member separated by a minor depression.
Wide areas, giving rise to oceanic depressions and leaving the continents protuberant; the other, folding along comparatively narrow belts, giving rise to mountain ranges.
The - - study of tidal strain in the earth's crust by Sir George Darwin has led that physicist to indicate the possibility of the triangular form and southerly direction of the continents being a result of the differential or tidal attraction of the sun and moon.
The geographical distribution of mountains is intimately associated with the great structural lines of the continents of which they form the culminating region.
The direct geographical elements are the arrangement of land and sea (continents and islands standing in sharp contrast) and the vertical relief of the globe, which interposes barriers of a less absolute kind between portions of the same land area or oceanic depression.
But while some large families, such as the Staphylinidae (rove-beetles) are especially abundant on the great northern continents, becoming scarcer in the tropics, others, the Cicindelidae (tiger-beetles), for example, are most strongly represented in the warmer regions of the earth, and become scarce as the collector journeys far to south or north.
The Ordovician and Silurian systems are widely developed, and it is most probable that, with the exception of the Archean continents of Finland and the S, the sea covered the whole of Russia.
Naturally the company named does not reach all of these points, but its line across the Andes supplies the indispensable link of communication, in the absence of which the east coast towns and the west coast towns have hitherto been as widely separated as if they had been located on different continents-indeed, far more widely separated in point of time and of freight charges than Great Britain and the United States.
- Lying midway between three continents, Crete was from the earliest period a natural stepping-stone for the passage of early culture from Egypt and the East to mainland Greece.
ASIA, the name of one of the great continents into which the earth's surface is divided, embracing the north-eastern portion of the great mass of land which constitutes what is generally known as the Old World, of which Europe forms the northwestern and Africa the south-western region.
The formation of this and of the other great mountain chains of central Asia resulted in the isolation of portions of the former central sea; and the same forces finally led to the elevation of the whole region and the union of the old continents of Angara and Gondwana.
But the case is quite different if one looks at the two continents as a whole, for improvement in means of communication has brought about strange vicissitudes, and western Europe has asserted her power in middle and eastern Asia.
A large and dominant Holoarctic fauna, with numerous subdivisions, ranges over the great northern continents, and is characterized by the abundance of certain families like the Carahidae and Staphylinidae among the Coleoptera and the Tenthredinidae among the Hymenoptera.
Bologninus Zalterius on a map of 1566, and Mercator on his famous chart of 1569, separates the two continents by a narrow strait which they call Streto de Anian, thus anticipating the discovery of Bering Strait by more than a hundred and fifty years.
2 The great plateau of North America, also turning its narrower point towards Bering Strait, naturally suggests the idea that there was a period in the history of our planet when the continents turned their narrow extremities towards the northern pole, as now they turn them towards the southern.
Notices in Greek authors are collected by P. Paulitschke, Die geographische Erforschung des afrikanischen Continents (Vienna, 1880); the inscriptions were edited and interpreted by G, Maspero, Revue archeol.
Fauna.Japan is an exception to the general rule that continents are richer in fauna than are their neighboring islands.
Here you find articles in the encyclopedia on topics related to places on the world outside the continents of Europe, Asia and Africa and the Americas.
Indeed, some of the chief contrasts of the two continents arise not so much from geological unlikeness as from their unsymmetrical situation with respect to the equator, whereby the northern one lies mostly in the temperate zone, while the southern one lies mostly in the torrid zone.
The two assertions are not to be reconciled by pointing out that Professor Tornebohm underestimated, for instance crediting the United States with only 1 1 billion tons, whereas the United States Geological Survey's expert credits that country with from ten to twenty times this quantity; nor by pointing out that only certain parts of Europe and a relatively small part of North America have thus far been carefully explored for iron ore, and that the rest of these two continents and South America, Asia and Africa may reasonably be expected to yield very great stores of iron, and that pyrite, one of the richest and most abundant of ores, has not been included.
Complex projects can be carried out on multiple continents through project management tools.
Beside, there were wafted to me evidences of unexplored and uncultivated continents on the other side.
Nay, be a Columbus to whole new continents and worlds within you, opening new channels, not of trade, but of thought.