Page images
PDF
EPUB

South

The French directed their enterprise more in the direction of cnce and course of the river Niger, which was believed by some North America than of the Indies. One of their most distinguished authorities to be identical with the Congo. Mungo Park, then an Freach in explorers was Samuel Champlain, a captain in the navy, assistant surgeon of an India man, volunteered his services, which North

were accepted by the association, and in 1795 he succeeded in who, after a remarkable journey through Mexico and the America.

West Indies from 1999 to 1602, established his historic reaching the town of Segu on the Niger, but was prevented from

connexion with Canada, to the geographical knowledge continuing his journey to Timbuktu. °Five years later he accepted of which he made a very large addition.

an offer from the government to command an expedition into the The principles and methods of surveying and position finding interior of Africa, the plan being to cross from the Gambia to the had by this time become well advanced, and the most remarkable Niger and descend the latter river to the sea. After losing most of Mission

example of the early application of these improvements his companions he himself and the rest perished in a rapid on the aries in

is to be found in the survey of China by Jcsuit missionaries. Niger at Busa, having been attacked from the shore by order of a the East.

They first prepared a map of the country round Peking, chief who thought he had not received suitable presents. His work,

which was submitted to the emperor Kang-hi, and, however, had established the fact that the Niger was not identical being satisfied with the accuracy of the European method of survey with the Congo. ing, he resolved to have a survey made of the whole empire on the While the British were at work in the direction of the Niger, the same principles. This great work was begun in July 1708, and the Portuguese were not unmindful of their old exploring fame. in completed maps were presented to the emperor in 1718.. The 1798 Dr F. J. M. de Lacerda, an accomplished astronomer, was records preserved in each city were examined, topographical infor- appointed to command a scientific expedition of discovery to the mation was diligently collected, and the Jesuit fathers checked their north of the Zambesi. He started in July, crossed the Muchenja triangulation by meridian altitudes of the sun and pole star and by a Mountains, and reached the capital of the Cazembe, where he died system of remcasurements. The result was a more accurate map of of fever. Lacerda left a valuable record of his adventurous journey: China than existed, at that time, of any country in Europe. Kang-hi but with Mungo Park and Lacerda thc history of African exploration next ordered a similar map to be made of Tibet, the survey being in the 18th century closes. executed by two lamas who were carefully trained as surveyors In South America scientific exploration was active during this by the Jesuits at Peking, from these surveys were constructed period. The great gcographical event of the century, as regards the well-known maps which were forwarded to Duhalde, and which that continent, was the measurement of an arc of the D'Anville utilized for his atlas.

meridian. The undertaking was proposed by the French

America Several European missionaries had previously found their way Academy as part of an investigation with the object from India to Tibet. Antonio Andrada, in 1624, was the first of ascertaining the length of the degree near the equator and near the The 18th European to enter Tibet since the visit of Friar Odoric pole respectively so as to determine the figure of the carth. A century

in 1325. The next journey was that of Fathers Grueber commission lest' Paris in 1735, consisting of Charles Marie de la

and Dorville about 1660, who succeeded in passing from Condamine, Pierre Bouguer, Louis Godin and Joseph de Jussieu China, through Tibet, into India. In 1715 Fathers Desideri and the naturalist... Spain appointed two accomplished naval Officers, Freyre made their way from Agra, across the Himalayas, to Lhasa, the brothers Ulloa, as coadjutors. The operations were carried on and the Capuchin Friar Orazio della Penna resided in that city during eight years on a plain to the south of Quito; and, in addition from 1735 until 1747. But the most remarkable journey in this to his memoir on this memorable measurement, La Condamine direction was performed by a Dutch traveller named Samuel van de collected much valuable geographical information during a voyage Putte. He left Holland in 1718, went by land through Persia to down the Amazon. The arc measured was 3° 7' 3" in length; India, and eventually

made his way to Lhasa, where he resided for a and the work consisted of two measured bases connected by a series long time. He went thence to China, returned to Lhasa, and was of triangles, one north and the other south of the equator, on the in India in time to be an eye-witness of the sack of Delhi by Nadir meridian of Quito. Contemporaneously, in 1738, Pierre Louis Asla.

Shah in 1737. In 1743 he left India and died at Batavia Moreau de Maupertuis, Alexis Claude Clairaut, Charles Etienne

on the 27th of September 1745 The premature death Louis Camus, Pierre Charles Lemonnier and the Swedish physicist of this illustrious traveller is the more to be lamented because his Celsius measured an arc of the meridian in Lapland. vast knowledge died with him. Two English missions sent by The British and French governments despatched several expedie Warren Hastings to Tibet, one led by George Bogle in 1774, and the tions of discovery into the Pacific and round the world during the other by Captain Turner in 1783, complete Tibetan exploration in 18th century. They were preceded by the wonderful the 18th century.

and romantic voyages of the buccaneers. The narratives

Pacillc From Persia much new information was supplied by Jean Chardin, of such men as Woodes Rogers, Edward Davis, George

Ocean. Jean Tavernier, Charles Hamilton, Jean de Thévenot and Father Shelvocke, Clipperton and William Dampier, can never Jude Krusinski, and by English traders on the Caspian. In 1738 fail to interest, while they are not without geographical value. John Elton traded between Astrakhan and the Persian port of The works of Dampier are especially valuable, and the narratives Enzeli on the Caspian, and undertook to build a fleet for Nadir of William Funnell and Lionel Wafer furnished the best accounts Shah. Another English merchant, named Jonas Hanway, arrived then extant of the Isthmus of Darien. . Dampier's literary ability at Astrabad from Russia, and travelled to the camp of Nadir at eventually secured for him a commission in the king's service; Kazvin. One lasting and valuable result of Hanway's

wanderings and he was sent on a voyage of discovery, during which he explored was a charming book of travels. In 1700 Guillaume Delisle pub- part of the coasts of Australia and New Guinea, and discovered the lished his map of the continents of the Old World; and his successor strait which bears his name bet'veen New Guinea and New Britain, D'Anville produced his map of India in 1752. D'Anville's map returning in 1701. In 1721 Jacob Roggewein was despatched on a contained all that was then known, but ten years afterwards Major voyage of some importance across the Pacific by the Dutch West Rennell began his surveying labours, which extended over the India Company, during which he discovered Easter Island on the period from 1763 to 1782. His survey covered an arca 900 m. long 6th of April 1722. by 300 wide, from the eastern confines of Bengal to Agrá, and from The voyage of Lord Anson to the Pacific in 1740-1744 was of a the Himalayas to Calpi. Rennell was indelatigable in collecting predatory character, and he lost more than half his men from scurvy: geographical information; his Bengal atlas appeared in 1781, his while it is not pleasant to reflect that at the very time when the famous map of India in 1788 and the memoir in 1792. Surveys French and Spaniards were measuring an arc of the meridian at were also made along the Indian coasts.

Quito, the British under Anson were pillaging along the coast of the Arabia received very careful attention, in the 18th century, Pacific and burning the town of Payta. But a romantic interest from the Danish scientific mission, which included Carsten Niebuhr attaches to the wreck of the "Wager," one of Anson's Acet, on a among its members. Niebuhr landed at Loheia, on the coast of desert island near Chiloe, for it bore fruit in the charming narrative Yemen, in December 1762, and went by land to Sana. All the other of Captain John Byron, which will endure for all time. In 1764 members of the mission died, but he proceeded from Mokha to Byron bimself was sent on a voyage of discovery round the world, Bombay.. He then made a journey through Persia and Syria to which led immediately after his return to the despatch of another Constantinople, returning to Copenhagen in 1767. His valuable to complete his work, under the command of Captain Samnuel Wallis. work, the Descriplion of Arabia, was published in 1772, and was The expedition, consisting of the “ Dolphin commanded by followed in 1774-1778 by two volumes of travels in Asia. The great Wallis, and the "Swallow" under Captain Philip Carteret, sailed in traveller survived until 1815, when he died at the age of eighty-two. September 1766, but the ships were separated on entering the Pacific

James Bruce of Kinnaird, the contemporary of Niebuhr, was from the Strait of Magellan. Wallis discovered Tahiti on the 19th equally devoted to Eastern travel; and his principal geographical of June 1767, and he gave a detailed account of that island. He Africa.

work was the tracing of the Blue Nile from its source to returned to England in May 1768. Carteret discovered the Charlotts

its junction with the White Nile. Before the death of and Gloucester Islands, and Pitcairn Island on the 2nd of July 1767: Bruce an African Association was formed, in 1788, for collecting revisited the Santa Cruz group, which was discovered by Mendatia information respecting the interior of that continent, with Major and Quiros; and discovered the strait separating New Britain from Rennell and Sir Joseph Banks as leading members. The association New Ireland. He reached Spithead again in February 1769. Wallis first employed John Ledyard (who had previously made an extra and Carterct were followed very closely by the French expedition ordinary journey into Siberia) to cross Africa from east to west of Bougainville, which sailed from Nantes in November 1766. on the parallel of the Niger, and William Lucas to cross the Sahara Bougainville had first to perform the unpleasant task of delivering to Fezzan. Lucas went from Tripoli to Mesurata, obtained some up the Falkland Islands, where he had encouraged the formation information respecting Fezzan and returned in 1789. One of the of a French settlement, to the Spaniards. He then entered the chiel problems the association wished to solve was that of the exist. ! Pacifc, and reached Tahiti in April 1768. Passing through the New

The

Arctic

Hebrides group he touched at Batavia, and arrived at St Malo after name, and in 1998 he and Flinders were surveying on the east coast an absence of two years and four months.

of Van Diemen's land. The three voyages of Captain James Cook form an era in the history Yet another outcome of Captain Cook's work was the voyage of of geographical discovery. In 1767 he sailed for Tahiti

, with the George Vancouver, who had served as a midshipman in Cook's Captala

object of observing the transit of Venus, accompanied second and third voyages. The Spaniards under Quadra had begun Cook

by two naturalists, Sir Joseph Banks and Dr Solander, a survey of north-western America and occupied Nootka Sound,

a pupil of Linnaeus, as well as by two astronomers. The which their government eventually agreed to surrender. Captain transit was observed on the 3rd of June 1769. After exploring Vancouver was sent out to receive the cession, and to survey the Tahiti and the Society group; Cook spent six months surveying New coast from Cape Mendocino northwards. He commanded the old Zealand, which he discovered to be an island, and the coast of New Discovery," and was at work during the seasons of 1792, 1793 and South Wales from latitude 38° S. to the northern extremity. The 1794. wintering

at Hawaii. Returning

home in 1795, he completed belief in a vast Antarctic continent stretching far into the temperate his narrative and a valuable series of charts. zone had never been abandoned, and was vehemently asserted by The 18th century saw the Arctic coast of North America reached Charles Dalrymple, a disappointed candidate nominated by the at two points, as well as the first scientific attempt to reach the Royal Society for the command of the Transit expedition of 1769. North Pole. The Hudson Bay Company had been inIn 1772 the French explorer Yves Kerguelen de Tremarec had dis- corporated in 1670, and its servants soon extended their covered the land that bears his name in the South Indian Ocean operations over a wide area to the north and west of

regloas. without recognizing it to be an island, and naturally believed it Canada. In 1741 Captain Christopher Middleton was ordered to to be part of the southern continent.

solve the question of a passage from Hudson Bay to the westward. Cook's second voyage was mainly intended to settle the question Leaving Fort Churchill in July 1742, he discovered the Wager river of the existence of such a continent once for all, and to define the and Repulse Bay. He was followed by Captain W. Moor in 1746, limits of any land that might exist in navigable seas towards the and Captain Coats in 1751, who examined the Wager Inlet up to the Antarctic circle. James Cook at his first attempt reached a south end. In November 1769 Samuel Hearne was sent by the Hudson latitude of 57° 15'. On a second cruise from the Society Islands, Bay Company to discover the sea on the north side of America, in 1773, he first of all men, crossed the Antarctic circle, and was but was obliged to return. In February 1770 he set out again from stopped by ice in 71° 10' $. During the second voyage Cook visited Fort Prince of Wales; but, after great hardships, he was again Easter Island, discovered several islands of the New Hebrides and forced to return to the fort. He started once more in December New Caledonia; and on his way home by Cape Horn, in March 1774.771, and at length reached the Coppermine river, which he surveyed he discovered the Sandwich Island group and described South to its mouth, but his observations are unreliable. With the same Georgia. He proved conclusively, that any southern continent object Alexander Mackenzie, with a party of Canadians, set out from that might exist lay under the polar ice. The third voyage was Fort Chippewyan on the 3rd of June 1789, and descending the great intended to attempt the passage from the Pacific to the Atlantic by river which now bears the explorer's name reached the Arctic sea. the north-cast. The “ Resolution" and " Discovery " sailed in In February 1773 the Royal Society submitted a proposal to the 1776, and Cook again took the route by the Cape of Good Hope. king for an expedition towards the North Pole. The expedition was On reaching the North American coast, he proceeded northward, fitted out under Captains Constantine Phipps and Skeffington fixed the position of the western extremity of America and surveyed Lut widge, and the highest latitude reached was 80° 48' N., but no Bering Strait. He was stopped by the ice in 70° 41' N., and named opening was discovered in the heavy Polar pack. The most imthe farthest visible point on the American shore Icy Cape. He then portant Arctic work in the 18th century was performed by the visited the Asiatic shore and discovered Cape North. Returning to Russians, for they succeeded in delineating the whole of the northern Hawaii, Cook was murdered by the natives. On the 14th of February coast of Siberia. Some of this work was possibly done at a still 1779, his second, Captain Édward Clerke, took command, and earlier date. The Cossack Simon Dezhneff is thought to have made a proceeding to Petropavlovsk in the following summer, he again voyage in the summer of 1648, from the river Kolyma, through examined the edge of the ice, but only got as far as 70° 33' N. The Bering Strait (which was rediscovered by Vitus Bering in 1728) to ships returned to England in October 1780.

Anadyr. Between 1738 and 1750 Manin and Sterlegolf made their In 1785 the French government carefully fitted out an expedition way in small sloops from the mouth of the Yenesci as far north as of discovery at Brest, which was placed under the command of 75° 15' N. The land from Taimyr to Cape Chelyuskin, the most Francois La Pérouse, an accomplished and experienced officer. northern extremity of Siberia, was mapped in many years of patient After touching at Concepcion in Chile and at Easter Island, La exploration by Chelyuskin, who reached the extreme point Pérouse proceeded to Hawaii and thence to the coast of California, (77° 34' N.) in May 1742. To the east of Cape Chelyuskin the of which he has given a very interesting account. He then crossed Russians encountered greater difficulties. They built small vessels the Pacific to Macao, and in July 1787 he proceeded to explore the at Yakutsk on the Lena, 900 m. from its mouth, whence the first Gulf of Tartary and the shores of Sakhalin, remaining some time at expedition was despatched under Lieut. Prontschichev in 1735. He Castries Bay, so named after the French minister of marine. Thence sailed from the mouth of the Lena to the mouth of the Olonek, he went to the Kurile Islands and Kamchatka, and sailed from the where he wintered, and on the 1st of September 1736 he got as far far north down the meridian to the Navigator and Friendly Islands. as 77° 29' N., within 5 m. of Cape Chelyuskin. Both he and his He was in Botany Bay in January 1788; and sailing thence, the young wife died of scurvy, and the vessel returned. A second explorer, his ship and crew were never seen again. Their fate was expedition, under Lieut. Laptyev, started from the Lena in 1739, long uncertain." In September 1791 Captain Antoine d'Ertre but encountered masses of drist ice in Chatanga bay, and with this casteaux sailed from Brest with two vessels to seek for tidings. ended the voyages to the westward of the Lena. Several attempts He visited the New Hebrides, Santa Cruz, New Caledonia and Solo were also made to navigate the sea from the Lena to the Kolyma. mon Islands, and

made careful though rough surveys of the Louisiade In 1736 Licut. Laptyev sailed, but was stopped by the drist ice in Archipelago, islands north of New Britain and part of New Guinea. August, and in 1739, during another trial,' he reached the mouth D'Entrecasteaux died on board his ship on the 20th of July 1793. of the Indigirka, where he wintered. In the season of 1740 he without ascertaining the fate of La Pérouse. Captain Peter Dillon continued his voyage to beyond the Kolyma, wintering at Nizhni at length ascertained, in 1828, that the ships of La Pérouse had been Kolymsk. In September 1740 Vitus Bering sailed from Okhotsk wrecked on the island Vanik during a hurricane.

on a second Arctic voyage with George William Steller on board The work of Captain Cook bore fruit in many ways. His master, as naturalist. In June 1741 he named the magnificent peak on the Captain William Bligh, was sent in the " Bounty" to convey bread coast of North America Mount St Elias and explored the Aleutian fruit plants from Tahiti to the West Indies. He reached Tahiti in Islands. In November the ship was wrecked on Bering Island; October 1788, and in April 1789 a mutiny broke out, and he, with and the gallant Dane, worn out with scurvy, died there on the several officers and men, was thrust into an open boat in mid-ocean. 8th of December 1741. In March 1770 a merchant named Liakhov During the remarkable voyage he then made to Timor, Bligh saw a large herd of reindeer coming from the north to the Siberian passed amongst the northern islands of the New Hebrides, which coast, which induced him to start in a sledge in the direction whence he named the Banks Group, and made several running surveys. they came. Thus he reached the New Siberian or Liakhov Islands, He reached England in March 1790. The "Pandora," under and for years afterwards the seekers for sossil ivory resorted to them. Captain Edwards, was sent out in search of the "Bounty," and The Russian Captain Vassili Chitschakov in 1765 and 1766 made two discovered the islands of Cherry and Mitre, east of the Santa Cruz persevering attempts to penetrate the ice north of Spitsbergen, group, but she was eventually lost on a reef in Torres Strait. In and reached 80° 30' N., while Russian parties twice wintered at Beli 1796-1797 Captain Wilson, in the missionary ship“ Duff." discovered Sound. the Gambier and other islands, and rediscovered the islands known In reviewing the progress of geographical discovery thus far, it to and seen by Quiros, but since called the Duff Group: Another has been possible to keep fairly closely, to a chronological order: result of Captain Cook's work was the colonization of Australia. But in the 19th century and after exploring work was so

Geoarrived in Botany Bay in the Supply " and "Sirius," followed by was in so many cases narrowed down from long journeys On the 18th of January 1788 Admiral Phillip.and. Captain Hunter generally and stcadily

maintained in all directions, and

graphical six transports, and established a colony at Port Jackson. Surveys to detailed surveys within relatively small areas, that it were then undertaken in several directions. In 1795 and 1796 becomes desirable to cover the whole period at one view for certain Matthew Flinders and George Bass were engaged on exploring work great divisions of the world. (See AFRICA; Asia; AUSTRALIA; POLAR in a small boat called the "Tom Thumb." In 1797 Bass, who had | REGIONS; &c.) Here, however, may be noticed the development been a surgeon, made an expedition southwards, continued the work of geographical societies devoted to the encouragement of exploration of Cook from Ram Head, and explored the strait which bears his and research. The first of the existing geographical societies was

societles.

that of Paris, founded in 1825 under the title of La Société de to geology, and can be completely studied only by geological Géographie. The Berlin Geographical Society (Gesellschaft für methods. But the relief of the crust is not a finished piece of sculpErdkunde) is second in order of seniority, having been founded in ture; the forms are for the most part transitional, owing 1827. The Royal Geographical Society, which was founded in their characteristic outlines to the process by which they

Cleomorph

ology. London in 1830, comes third on the list; but it may be viewed as a are produced; therefore the geographer must, for strictly direct result of the earlier African Association founded in 1788. geographical purposes, take some account of the processes which are Sir John Barrow, Sir John Cam

Hobhouse (Lord Broughton), Sir now in action modifying the forms of the crust. Opinion still differs Roderick Murchison, Mr Robert Brown and Mr Bartle Frere formed as to the extent to which the geographer's work should overlap that the foundation committee of the Royal Geographical Society, and of the geologist. the first president was Lord Goderich. The action of the society in The primary distinction of the forms of the crust is that between supplying practical instruction to intending travellers, in astronomy, elevations and depressions. Granting that the geoid or mean surveying and the various branches of science useful to collectors, surface of the ocean is a uniform spheroid, the distribution of land has had much to do with advancement of discovery. Since the war and water approximately indicates a division of the surlace of the of 1870 many geographical societies have been established on the globe into two areas, one of elevation and one of depression. The continent of Europe. At the close of the 19th century there were increasing number of measurements of the height of land in all upwards of 100 such societies in the world, with more than 50,000 continents and islands, and the very detailed levellings in those members, and over 150 journals were devoted entirely to geographical countries which have been thoroughly surveyed, enable the average sobjects. The great development of photography has been a notable elevation of the land above sea-level to be fairly estimated, although aid to explorers, not only by placing at their disposal a faithful and many vast gaps in accurate knowledge remain, and the estimate ready means of recording the features of a country and the types is not an exact one. The only part of the sea-bed the configuration of inhabitants, but by supplying a method of quick and accurate of which is at all well known is the zone bordering the coasts where topographical surveying.

the depth is less than about 100 fathoms or 200 metres, i.e. those THE PRINCIPLES OF GEOGRAPHY

parts which sailors speak of as " in soundings." Actual or projected

routes for telegraph cables across the deep sea have also been sounded As regards the scope of geography, the order of the various with extreme accuracy in many cases; but beyond these lines of departments and their inter-relation, there is little difference of sounding the vast spaces of the ocean remain unplumbed save for opinion, and the principles of geography: are now generally accepted the rare researches of scientific expeditions, such as those of the by modern geographers. The order in which the various subjects Challenger," the “ Valdivia," the "Albatross " and the "Scotia." are treated in the following sketch is the natural succession from Thus the best approximation to the average depth of the ocean is fundamental to dependent facts, which corresponds also to the little more than an expert guess; yet a fair approximation is probable evolution of the diversities of the earth's crust and of its inhabitants. for the features of sub-oceanic relief are so much more uniform than

The fundamental geographical conceptions are mathematical, the those of the land that a smaller number of fixed points is required relations of space and form. The figure and dimensions of the to determine them. Mathems.

earth are the first of these. They are ascertained by a The chief element of uncertainty as to the largest features of the tical geo

combination of actual measurement of the highest relief of the earth's crust is due to the unexplored area in the Arctic graphy, precision on the surface and angular observations of the region and the larger regions of the Antarctic, of which

Crustal positions of the heavenly bodies. The science of geodesy we know nothing. We know that the earth's surface if

nellek is part of mathematical geography, of which the arts of surveying unveiled of water would exhibit a great region of elevation and cartography are applications. The motions of the earth arranged with a certain rough radiate symmetry round the north as a planet must be taken into account, as they render possible pole, and extending southwards in three unequal arms which ta per the determination of position and direction by observations of the to points in the south. A depression surrounds the little-known heavenly bodies. The diurnal rotation of the earth furnishes two south polar region in a continuous ring and extends northwards in fixed points or poles, the axis joining which is fixed or nearly so in its three vast hollows lying between the arms of the elevated area. So direction in space. The rotation of the earth thus fixes the directions far only is it possible to speak with certainty, but it is permissible of north and south and defines those of east and west. The angle to take a few steps into the twilight of dawning knowledge and which the earth's axis makes with the plane in which the planet indicate the chief subdivisions which are likely io be established revolves round the sun determines the varying seasonal distribution in the great crust-hollow and the great crust-heap. The boundary of solar radiation over the surface and the mathematical zones of between these should obviously be the mean surface of the climate. Another important

consequence of rotation is the deviation sphere. produced in moving bodies relatively to the surlace. In the form Sir John Murray deduced the mean height of the land of the globe known as Ferrell's Law this runs:" If a body moves in any direction as about 2250 ft. above sea-level, and the mean depth of the oceans on the earth's surface, there is a deflecting force which arises from as 2080 fathoms or 12,480 st. below sea-level. Calculating the area the carth's rotation which tends to deflect it to the right in the of the land at 55,000,000 sq. m. (or 28.6% of the surface), and that northern hemisphere but to the left in the southern hemisphere." of the oceans as 137,200,000 sq. m. (or 71.4% of the surface), he The deviation is of importance in the movement of air, of ocean

found that the volume of the land above sea-level was 23.450,000 currents, and to some extent of rivers.

cub. m., the volume of water below sea-level 323.800.000, and the In popular usage the words “physical geography" have come total volume of the water equal to about chath of the volume of the to mean geography viewed from a particular standpoint rather whole globe. From these data, as revised by A. Supan. H. R. Mill Physkal than any special department of the subject. The popular calculated the position of mean sphere-level at about 10.000 ft. or

is better conveyed by the word physiography, a 1700 fathoms below sea-level. meaning

He showed that an imaginary geography.

term which appears to have been introduced by Linnaeus, spheroidal shell, concentric with the earth and cutting the slope and was reinvented as a substitute for the cosmography of the middle between the clevated and depressed areas at the contour-line of 1700 ages by Professor Huxley. Although the term has since been limited fathoms, would not only leave above it a volume of the crust equal by some writers to one particular part of the subject, it seems best to the volume of the hollow left below it, but would also divide the to maintain the original and literal meaning. In the stricter sense, surface of the earth so that the area of the elevated region was physical gcography is that part of geography which involves the equal to that of the depressed region. processes of contemporary change in the crust and the circulation A similar observation was made almost simultaneously by of the fluid envelopes. It thus draws upon physics for the explana Romieux,? who further speculated on the equilibrium between the tion of the phenomena with the space-relations of which it is specially weight of the elevated land mass and that of the total concerned." Physical geography naturally falls into three divisions, waters of the ocean, and deduced some interesting rela- Areas of dealing respectively with the surface of the lithosphere-geomor- tions between them. Murray, as the result of his study, according phology; the hydrosphere-oceanography; and the atmosphere divided the earth's surface into three zones-the continental

to Murray. climatology: All these rest upon the facts of mathematical geo area containing all dry land, the transitional area including graphy, and the three are so closely inter-related that they cannot the submarine

slopes down to 1000 fathoms, and the abysmal area be rigidly separated in any discussion.

consisting of the Hoor of the ocean beyond that depth; and Mill Geomorphology is the part of geography which deals with terres. proposed to take the line of mean-sphere level, instead of the em. trial relief, incluing the submarine as well as the subaërial portions pirical depth of 1000 sathoms, as the boundary between the transi. of the crust. The history of the origin of the various forms belongs tional and abysmal areas. "H. Wagner's year-book, Geographische Jahrbuch, published at

An elaborate criticism of all the existing data regarding the Gotha, is the best systematic record of the progress of geography 1894 by Professor Hermann

Wagner, whose recalculations of volumes

volume relations of the vertical relief of the globe was made in in all departments; and Haack's Geographen Kalender, also published annually at Gotha, gives complete lists of the geographical societies and geographers of the world.

." On the Height of the Land and the Depth of the Ocean," Scol. * This phrase is old, appearing in one of the earliest English works Geog. Mag. iv. (1888), p. I. Estimates had been made previously by on geography.' William Cuningham's Cosmographical Glasse con Humboldt, De Lapparent, H. Wagner, and subsequently by Penck leinyng the pleasant Principles of Cosmographie, Geographic, Hydro- and Heiderich, and for the oceans by Karstens, graphie or Navigation (London, 1559).

6 Petermanns Milleilungen, xxv. (1889), p. 17. See also S. Günther, Handbuch der mathematischen Geographie Proc. Roy. Soc. Edin. xvii. (1890) p. 185. (Stuttgart, 1890).

Comples rendus Acad. Sci. (Paris, 1890), vol. üi. p. 994

[ocr errors]

9

6

and mean heights—the best results which have yet been obtained second great series of crust waves from north to south, giving rise led to the following conclusions."

by their interference to six great elevated masses (the continents). The area of the dry land was taken as 28-3% of the surface of the arranged in three groups, each consisting of a northern and a globe, and that of the oceans as 71.7%. The mean height deduced southern member separated by a minor depression. These elevated

for the land was 2300 lt. above sea level, the mean depth masses are divided from one another by similar great depressions. Anes of

of the sea 11.500 it. below, while the position of mean. He says: “ The surface of each of our great continental masses of the crust

sphere level comes out as 7500 ft. (1250 fathoms) below land resembles that of a long and broad arch-like form, of accordlag

sea-level. From this it would appear that 43% of the which we see the simplest type in the New World. The to Wagoer. earth's surface was above and 57% below the mean surface of the North American arch is sagged down.

worth's level. It must be noted, however, that since 1895 the soundings wards in the middle into a central depression which

fold. Belgica, " of Nansen in the north polar area, of the “ Valdivia,"

theory.

lies between two long marginal plateaus, and these Gauss" and " Scotia in the Southern Ocean, and of various plateaus are finally crowned by the wrinkled crests which form its surveying ships in the North and South Pacific, have proved that two modern mountain systems. The surface of each of our ocean the mean depth of the ocean is considerably greater than had been foors exactly resembles that of a continent turned upside down. supposed, and mean-sphere level must therefore fie deeper than the Taking the Atlantic as our simplest type, we may say that the calculations of 1895 show: possibly not far from the position deduced surface of an ocean basin resembles that of a mighty trough or from the freer estimate of 1888. The whole of the available data syncline, buckled up more or less centrally in a medial ridge, which were utilized by the prince of Monaco in 1905 in the preparation of a is bounded by two long and deep marginal hollows, in the cores complete bathymetrical map of the oceans on a uniform scale, of which still deeper grooves sink to the profoundest depths. This which must long remain the standard work for reference on ocean complementary relationship descends even to the minor features depths.

of the two. Where the great continental sag sinks below the ocean By the device of a hypsographic curve co-ordinating the vertical level, we have our gulfs and our Mediterraneans, seen in our type relief and the areas of the earth's surface occupied by each zone of continent, as the Mexican Gulf and Hudson Bay. Where the elevation, according to the system introduced by Supan," Wagner central oceanic buckle attains the water-line we have our oceanic showed his results graphically.

islands, seen in our type ocean, as St Helena and the Azores. AlThis curve with the values reduced from metres to feet is re- though the apparent crust-waves are neither equal in size nor produced below.

symmetrical in form, this complementary relationship between Wagner subdivides the earth's surface, according to elevation, them is always discernible. The broad Pacific depression seems to into the following five regions:

answer to the broad elevation of the Old World--the narrow trough

of the Atlantic to the narrow continent of America." Wagner's Divisions of the Earth's Crust.

The most thorough discussion of the great features of terrestrial

relief in the light of their origin is that by Professor E. Suess, who Per cent of Name.

From

Το
Surface.

points out that the plan of the earth is the result of
two movements of the crust-one, subsidence over

Suess's wide areas, giving rise to oceanic depressions and leaving

theory. Depressed area

3

Deepest. 16,400 feet. the continents protuberant; the other, folding along comparatively Oceanic plateau.

54 16.400 feet.

7.400 narrow belts, giving rise to mountain ranges. This theory of crust Continental slope

7.400

660 blocks dropped by subsidence is opposed to Lapworth's theory of Continental plateau.

28

660

+ 3.000 vast crust-folds, but geology is the science which has to decide Culminating area

+ 3.300 Highest between them. The continental plateau might for purposes of detailed study be have been made as to the cause of the distribution of heap and

Geomorphology is concerned, however, in the suggestions which divided into the continental shelf from -660 st. to sea-level, and hollow in the larger leatures of the crust. Elie de Beaumont, in

lowlands from sea-level to +660 ft. (corresponding to
the mean level of the whole globe)." Uplands reaching ranges and their geological age and character, was feeling towards a

his speculations on the relation between the direction of mountain
from 660 ft. to 2300 (the approximate mean leve! of comprehensive theory of the forms of crustal relief; but his ideas
the land), and highlands, from 2300 upwards, might were too geometrical, and his theory that the earth is a spheroid
also be distinguished.
A striking fact in the configuration of the crust is determined the direction of mountain ranges, could not be proved.

built up on a rhombic dodecahedron, the pentagonal faces of which that each continent, or elevated mass of the crust, is The " tetrahedral theory" brought forward by Lowthian Green,' diametrically opposite to an ocean basin or great de- that the form of the earth is a spheroid based on a regular tetra

hedron, is more serviceable, because it accounts for three very Mean helgre of Lard-23001

interesting facts of the terrestrial plan--(1) the antipodal FONIINCTAL PLAILAU

Mean Lovel of Clode/Land and Seat 6500 position of continents and occan basins; (2) the tri-
Actuad Sea Level

angular outline of the continents; and (3) the excess of

sea in the southern hemisphere. Recent investigations Handel A he park's out:15000

have recalled attention to the work of Lowthian Green,

but the question is still in the controversial stage. The TORU.WIKIWE

study of tidal strain in the carth'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. More recently Professor A. E. H. Love has shown that the great features of the

relief of the lithosphere may be expressed by spherical Earth's Swrace 102

harmonics of the first, second and third degrees, and their formation related to gravitational action in a sphere of

unequal density.' pression; the only partial exception being in the case of southern In any case it is fully recognized that the plan of the earth is so

South America, which is antipodal to eastern Asia. clear as to leave no doubt as to its being due to some general cause Arrange.

Professor C. Lapworth has generalized the grand features which should be capable of detection. meat of

of crustal relief in a scheme of attractive simplicity. He If the level of the sea were to become coincident with the mean Hages and sees throughout all the chaos of irregular crust-forms the level of the lithosphere, there would result one tri-radiate land-mass hodows.

recurrence of a certain harmony, a succession of folds or of nearly uniform outline and one continuous sheet of water waves which build up all the minor features. One

Das Antlitz der Erde (4 vols., Leipzig, 1885, 1888, 1901). Transgreat series of crust waves from east to west is crossed by a

lated under the editorship of E. de Margerie, with much additional 1 " Areal und mittlere Erhebung der LandAachen sowie der Erd matter, as La Face de la terre, vols. i. and ii. (Paris, 1897, 1900), and kruste " in Gerland's Beiträge zur Geophysik, i. (1895) p. 667. See into English by Dr Hertha Sollas as The Face of the Earth, vols. i. also Nature, 54 (1896), p. 112.

and ii. (Oxford, 1904, 1906). * Petermanns Mitteilungen, xxxv. (1889) p. 19.

• Elie de Beaumont, Notice sur les systèmes de montagnes (3 vols., • The areas of the continental shell and lowlands are approxi- | Paris, 1852). mately equal, and it is an interesting circumstance that, taken as a Vestiges of the Mollen Globe (London, 1875). whole, the actual coast-line comes just midway on the most nearly * See J. W. Gregory, " The Plan of the Earth and its Causes," level belt of the earth's surface, excepting the ocean floor. The con- Geog. Journal, xiii. (1899), P: 225; Lord Avebury, ibid. xv. (1900) figuration of the continental slope has been treated in detail by p. 46; Marcel Bertrand, Déformation tetraédrique de la terre et Nansen in Scientific Results of Norwegian North Polar Expedition, déplacement du pôle," Comptes rendus Acad. Sci. (Paris, 1900). vol. iv. (1904), where full references to the literature of the subject vol. cxxx. P: 449; and A. de Lapparent, ibid. p. 614. will be found.

See A. E. H. Love, “ Gravitational Stability of the Earth," Phil. British Association Report (Edinburgh, 1892), p. 699.

Trans, ser. A. vol. ccvii. (1907) p. 171.

[ocr errors]

10000

5000

[ocr errors]

CONTIN

[ocr errors]
[ocr errors]

OGE KKTC PLATEAU

30000

Par cane arra

[ocr errors]

700.000 miles

13089

The code tipegts.

of con

broken by few islands. The actual position of sea level lies so near low coasts, subdividing cach group according as the coast-line runs the summit of the crust-heap that the varied relief of the upper parallel to or crosses the line of strike of the mountains, or is not

portion leads to the formation of a complicated coast. related to mountain structure. A further subdivision depends on line and a great number of detached portions of land. the character of the inter-relation of land and sea along the shore

The hydrosphere is, in fact, continuous, and the land is producing such types as a fjord-coast, ria-coast or lagoon-coast. all in insular masses: the largest is the Old World of Europe, This extremely elaborate subdivision may be reduced, as Wagner Asia and Africa;

the next in size, America; the third, possibly points out to three types--the continental coast where the sea comes Antarctica; the fourth, Australia; the fifth, Greenland. After up to the solid rock-material of the land; the marine coast, which is this there is a considerable gap before New Guinea, Borneo, Mada formed entirely of soft material sorted out by the sea; and the comgascar, Sumatra and the vast multitude of smaller islands descending posite coast, in which both forms are combined. in size by regular gradations to mere rocks. The contrast between On large-scale maps it is necessary to show two coast-lines, one island and mainland was natural enough in the days before the for the highest, the other for the lowest tide; but in small-scale discovery of Australia, and the mainland of the Old World was maps a single line is usually, wider than is required to

Coast traditionally divided into three continents. These, "continents," represent the whole breadih of the inter-tidal zone.

lioes. parts of the carth," or "quarters of the globe," proved to be The measurement of a coast-line is difficult, because convenient divisions; America was added as a fourth, and subse the length will necessarily be greater when measured on a large. quently divided into two, while Australia on its discovery was classed scale map, where minute irregularities can be taken into account. sometimes as a new continent, sometimes merely as an island, some It is usual to distinguish between the general coast-line measured times compromising!y as an island-continent, according to individual from point to point of the headlands disregarding the smaller bays, opinion. The discovery of the insularity of Greenland might again and the detailed coast-line which takes account of every inflection give rise to the argument as to the distinction between island and shown by the map employed, and follows up river entrances to the continent. Although the name of continent was not applied to point where tidal action ceases. The ratio between these two large portions of land for any physical reasons, it so happens that coast-lines represents the "coastal development" of any region. there is a certain physical similarity or homology between them While the forms of the sea-bed are not yet sufficiently well known which is not shared by the smaller islands or peninsulas.

to admit of exact classification, they are recognized to be as a rule The typical continental form is triangular as regards its sea-level distinct from the forms of the land, and the importance outline. The relief of the surface typically includes a central plain, of using a distinctive terminology is felt. Efforts have

Submarias

forms. Homology highlands or mountain ranges, loftier on one side than sometimes dipping below sea-level, bounded by, lateral been made to arrive at a definite international agreement

on this subject, and certain terms suggested by a committee were tlaeots.

on the other, the higher enclosing a plateau shut in by adopted by the Eighth International Geographical Congress at New mountains. 'South America and North America follow York in 1904. The forms of the ocean

floor include the "shell," this type most closely: Eurasia (the land mass of Europe and Asia) or shallow sea margin, the depression," a general term applied to comes next, while Africa and Australia are larther removed from all submarine hollows, and the elevation." A depression when of the type, and the structure of Antarctica and Greenland is unknown. great extent is termed a “basin," when it is of a more or less round

If the continuous, unbroken, horizontal extent of land in a conform with approximately equal diameters, a "trough" when it is tinent is termed its trunk,' and the portions cut up by, inlets or wide and elongated with gently sloping borders, and a trench channels of the sea into islands and peninsulas the limbs, it is possible when narrow and elongated with steeply sloping borders, one of to compare the continents in an instructive manner.

which rises higher than the other. The extension of a trough or The following table is from the statistics of Professor H. Wagner," basin penetrating the land or an, elevation is termed an “embay. his metric measurements being transposed into British units: ment when wide, and a "gully" when long and narrow; and the

deepest part of a depression is termed a deep: Comparison of the Continents.

A depression of small extent when steep-sided is

termed a "caldron," and a long narrow depression
Area
Area Mean

Area
penin-

Area
Area

crossing a part of the continental border is termed

Area total

a “furrow." An elevation of great extent which sulas,

islands, limbs, limbs,
mil.
feet.
mil.
mil.
mil.

rises at a very gentle angle from a surrounding mil. per

depression is termed a "rise," one which is rela. sq. m. sq. m. sq. m.

tively narrow and steep-sided a "ridge," and one

which is approximately equal in length and breadth Old World 2360

but steep-sided a "plateau," whether it springs New World

16.2
2230

direct from a depression or from a rise. An elevaEurasia 20-85 15.42 4.09 1.34 5:43 26

tion of small extent is distinguished as a "dome Africa 11.46 2130 11.22

0.24

when it is more than 100 fathoms from the surface, North America

9.26
2300
6.92 0.78 1.56 2.34

“bank" when it is nearer the surface than South America 6.84 1970

6-76
0.06 0-08

100 fathoms but deeper than 6 fathoms, and a Australia

3.43 1310

2.77
0.16
0-66

shoal " when it comes within 6 fathoms of the Asia 17.02 3120

3.05 1.04 4:09 24 surface and so becomes a serious danger to ship. Europe:

3.83
980
2.49 1.04 0.30 1.34 35 ping: The highest point of an clevation is termed

height," it it does not form an island or one The usual classification of islands is into continental and oceanic. of the minor forms. The former class includes all those which rise from the continental The forms of the dry land are of infinite variety, and have been

shelf, or show evidence in the character of their rocks of studied in great detail. From the descriptive or topographical Islands.

having at one time been continuous with a neighbouring point of view, geometrical form alone should be con Land continent. The latter rise abruptly from the oceanic abysses. sidered ; but the origin and geological structure of

formes Oceanic islands are divided according to their geological character land forms must in many cases be taken into account into volcanic islands and those of organic origin, including cora! when dealing with the function they exercise in the control of islands. More elaborate subdivisionsaccording tostructure, origin and mobile distributions. The geographers who have hitherto given position have been proposed. In some cases a piece of land is only most attention to the forms of the land have been trained as geoan island at high water, and by imperceptible gradation the form logists, and consequently there is a general tendency to make origin passes into a peninsula. The typical peninsula is connected with the or structure the basis of classification rather than form alone. mainland by a relatively narrow isthmus; the name is, however, ex The fundamental form-elements may be reduced to the six tended to any limb projecting from the trunk of the mainland, even proposed by Professor Penck as the basis of his double system of when, as in the Indian peninsula, it is connected by its widest part. Classification by form and origin. These may be looked

The six Small peninsulas are known as promontories or headlands, and upon as being all derived by various modifications or the extremity as a cape. The opposite form, an inlet of the sea, is arrangements of the single form-unit, the slope or inclined

elemeatary

land fores. Coasts.

known when wide as a gull, bay or bight, according plane surface. No one form occurs alone, but always

to size and degree of inflection, or as a fjord or ria when grouped together with others in various ways to make up districts, long and narrow. It is convenient to employ a specific name for a regions and lands of distinctive characters. The form-elements are: projection of a coast-line less pronounced than a peninsula, and for an inlet less pronounced than a bay or bight; outcurve and incurve

See Geographical Journal, xxii. (1903) pp. 191-194may serve the turn. The varieties of coast-lines were reduced to an • The most important works on the classifcation of land forms are exact

classification by Richthofen, who grouped them according to yon Richthofen, Führer für Forschungsreisende (Berlin, 1886): the height and slope of the land into clif-coasts (Steilküsten) G. de la Noë and E. de Margerie, Les Formes du terrain (Paris, 1888); narrow beach coasts with cliffs, wide beach coasts with cliffs, and and above all A. Penck, Morphologie der Erdoberflache (2 vols.,

Stuttgart, 1894)., Compare also A. de Lapparent, Leçons de géo Rumpf, in German, the language in which this distinction was graphie physique (2nd ed., Paris, 1898), and' W. M. Davis, Physical first made.

Geography (Boston, 1899). Lehrbuch der Geographie (Hanover and Leipzig, 1900), Bd. i. S. 6* Geomorphologie als genetische Wissenschaft," in Report of 245, 249.

Sixth International Geog. Congress (London, 1895), p. 735 (English ** See, for example, F. G. Hahn's Insel-Studien (Leipzig, 1883). Abstract, p. 748).

height, trunk,

sq. m.

Sq. m.

cent.

35-8

2620

0.24

a

2.1 25

1.1 19

0.02

0.50

12.93

a

« ՆախորդըՇարունակել »