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Ebook has 531 lines and 200896 words, and 11 pages

Transcriber's notes:

Characters following a carat were printed in superscript.

Side-notes were relocated to function as titles of their respective paragraphs.

Macrons and breves above letters and dots below letters were not inserted.

stands for the root symbol; , , etc. for greek letters.

The following typographical errors have been corrected:

ARTICLE MAP: "Far superior were the maps found among the semi-civilized Mexicans when the Spaniards first discovered and invaded their country." 'Spaniards' amended from 'Spainiards'.

ARTICLE MAP: "... he concluded that a degree of the meridian measured 700 stadia." 'meridian' amended from 'meridan'.

ARTICLE MAP: "Among geographers should be mentioned Posidonius , the head of the Stoic school of Rhodes ..." '135-51' amended from '13-551'.

ARTICLE MAP: "In Chile a comision topografica was appointed as long ago as 1848 ..." 'topografica' amended from 'topografico'.

ARTICLE MARDUK: "The name Mordecai denotes 'belonging to Marduk.'" 'Marduk' amended from 'Maduk'.

ARTICLE MARIGNAN, BATTLE OF: "... who were commanded on this day by the famous engineer Pedro Navarro." 'by' amended from 'be'.

ARTICLE MARINUS OF TYRE: "His chief merits were that he assigned to each place its proper latitude and longitude, and introduced improvements in the construction of his maps." 'longitude' amended from 'longtitude'.

ARTICLE MARIVAUX, PIERRE CARLET DE CHAMBLAIN DE: "Meanwhile his worldly affairs underwent a sudden revolution." 'worldly' amended from 'wordly'.

ARTICLE MARK, ST: "... 285 seq. ." 'special' amended from 'sepcial'.

ARTICLE MARKET: "... Rationale of Market Fluctuations; Robert Giffen, Stock Exchange Securities ..." 'Fluctuations' amended from 'Fluctations'.

ARTICLE MARRIAGE: "... to all this added the impediments created by 'spiritual affinity,' i.e. the relations established between baptizer and baptized ..." 'spiritual' amended from 'spirtual'.

ENCYCLOPAEDIA BRITANNICA

A DICTIONARY OF ARTS, SCIENCES, LITERATURE AND GENERAL INFORMATION

ELEVENTH EDITION

Map to Mars

ARTICLES IN THIS SLICE:

MAP MARIE LOUISE MAPLE, SIR JOHN BLUNDELL MARIENBAD MAPLE MARIENBERG MAPU, ABRAHAM MARIENBURG MAQQARI MARIENWERDER MAQRIZI MARIE TH?R?SE MAR, EARLDOM OF MARIETTA MAR, ERSKINE MARIETTA MAR, ERSKINE MARIETTE, AUGUSTE FERDINAND FRAN?OIS MAR, ERSKINE MARIGNAC, JEAN CHARLES GALISSARD DE MARA, GERTRUD ELISABETH MARIGNAN, BATTLE OF MARABOUT MARIGNOLLI, GIOVANNI DE' MARACAIBO MARIGNY, ENGUERRAND DE MARACAIBO MARIGNY, JEAN DE MARAGHA MARIGOLD MARANH?O MARIINSK MARANO MARILLAC, CHARLES DE MARASH MARINES MARAT, JEAN PAUL MARINETTE MARATHI MARINI, GIAMBATTISTA MARATHON MARINO MARAZION MARINUS MARBLE MARINUS MARBLEHEAD MARINUS OF TYRE MARBLES MARIO, GIUSEPPE MARBOT, JEAN BAPTISTE MARCELIN MARION, FRANCIS MARBURG MARION, HENRI FRAN?OIS MARBURG MARION MARBURG, COLLOQUY OF MARION MARCA, PIERRE DE MARIONETTES MARCANTONIO MARIOTTE, EDME MARCASITE MARIPOSAN MARCEAU-DESGRAVIERS, S?VERIN MARIS, JACOB MARCEL, ?TIENNE MARITIME PROVINCE MARCELLINUS, ST MARITIME TERRITORY MARCELLO, BENEDETTO MARIUPOL MARCELLUS MARIUS OF AVENCHES MARCELLUS MARIUS, GAIUS MARCESCENT MARIVAUX, PIERRE DE CHAMBLAIN DE MARCH, EARLS OF MARJORAM MARCH, AUZIAS MARK, ST MARCH, FRANCIS ANDREW MARK MARCH MARK, GOSPEL OF ST MARCH MARKBY, SIR WILLIAM MARCH MARKET MARCHE MARKET BOSWORTH MARCHE MARKET DRAYTON MARCHENA MARKET HARBOROUGH MARCHENA RUIZ DE CASTRO, JOS? MARKHAM, SIR CLEMENTS ROBERT MARCHES, THE MARKHAM, GERVASE MARCHMONT, EARLS OF MARKHAM, MRS MARCHPANE MARKHAM, WILLIAM MARCIAN MARKHOR MARCIANUS MARKIRCH MARCION & THE MARCIONITE CHURCHES MARKLAND, JEREMIAH MARCOMANNI MARKO KRALYEVICH MARCOS DE NIZA MARK SYSTEM MARCOU, JULES MARL MARCUS AURELIUS ANTONINUS MARLBOROUGH, EARLS AND DUKES OF MARCY, WILLIAM LEARNED MARLBOROUGH, JOHN CHURCHILL MARDIN MARLBOROUGH MARDUK MARLBOROUGH MARE MARLITT, E. MARE CLAUSUM and MARE LIBERUM MARLOW MAREE, LOCH MARLOWE, CHRISTOPHER MAREMMA MARLOWE, JULIA MARENGO MARLY-LE-ROI MAREOTIS MARMALADE MARE'S-TAIL MARMANDE MARET, HUGUES-BERNARD MARMIER, XAVIER MARGARET MARMONT, AUGUSTE FR?D?RIC LOUIS DE MARGARET, ST MARMONTEL, JEAN FRAN?OIS MARGARET, ST MARMORA MARGARET MARMORA, SEA OF MARGARET MARMOSET MARGARET MARMOT MARGARET OF ANJOU MARNE MARGARET OF AUSTRIA MARNE MARGARET OF AUSTRIA MARNIAN EPOCH MARGARET OF PROVENCE MAROCHETTI, CARLO MARGARET MAULTASCH MARONITES MARGARINE MAROONS MARGARITA MAROS-V?S?RHELY MARGATE MAROT, CL?MENT MARGGRAF, ANDREAS SIGISMUND MAROT, DANIEL MARGHELAN MARPLE MARGRAVE MARPRELATE CONTROVERSY MARGUERITE MARQUAND, HENRY GURDON MARGUERITE DE VALOIS MARQUARDT, JOACHIM MARGUERITTE, PAUL and VICTOR MARQUESAS MARHEINEKE, PHILIP KONRAD MARQUESS MARIANA, JUAN DE MARQUETRY MARIANAO MARQUETTE, JACQUES MARIANAS MARQUETTE MARIANAS MARR, CARL MARIANUS SCOTUS MARRADI, GIOVANNI MARIA STELLA MARRAKESH MARIA THERESA MARRI MARIAZELL MARRIAGE MARIE AM?LIE TH?R?SE MARRUCINI MARIE ANTOINETTE MARRUVIUM MARIE DE FRANCE MARRYAT, FREDERICK MARIE DE' MEDICI MARS, MLLE MARIE GALANTE MARS MARIE LESZCZYNSKA

Topographical maps and plans are drawn on a scale sufficiently large to enable the draughtsman to show most objects on a scale true to nature. Its information should not only be accurate, but also conveyed intelligibly and with taste. Exaggeration, however, is not always to be avoided, for even on the British 1 in. ordnance map the roads appear as if they were 130 ft. in width.

Chorographical and general maps are either reduced from topographical maps or compiled from such miscellaneous sources as are available. In the former case the cartographer is merely called upon to reduce and generalize the information given by his originals, to make a judicious selection of place names, and to take care that the map is not overcrowded with names and details. Far more difficult is his task where no surveys are available, and the map has to be compiled from a variety of sources. These materials generally include reconnaissance survey of small districts, route surveys and astronomical observations supplied by travellers, and information obtained from native sources. The compiler, in combining these materials, is called upon to examine the various sources of information, and to form an estimate of their value, which he can only do if he have himself some knowledge of surveying and of the methods of determining positions by astronomical observation. A knowledge of the languages in which the accounts of travellers are written, and even of native languages, is almost indispensable. He ought not to be satisfied with compiling his map from existing maps, but should subject each explorer's account to an independent examination, when he will frequently find that either the explorer himself, or the draughtsman employed by him, has failed to introduce into his map the whole of the information available. Latitudes from the observations of travellers may generally be trusted, but longitudes should be accepted with caution; for so competent an observer as Captain Speke placed the capital of Uganda in longitude 32? 44? E., when its true longitude as determined by more trustworthy observations is 32? 26? E., an error of 18?. Again, on the map illustrating Livingstone's "Last Journals" the Luapula is shown as issuing from the Bangweulu in the north-west, when an examination of the account of the natives who carried the great explorer's remains to the coast would have shown that it leaves that lake on the south.

The second group includes all maps compiled for special purposes. Their variety is considerable, for they are designed to illustrate physical and political geography, travel and navigation, trade and commerce, and, in fact, every subject connected with geographical distribution and capable of being illustrated by means of a map. We thus have physical maps in great variety, including geological, orographical and hydrographical maps, maps illustrative of the geographical distribution of meteorological phenomena, of plants and animals, such as are to be found in Berghaus's "Physical Atlas," of which an enlarged English edition is published by J. G. Bartholomew of Edinburgh; political maps, showing political boundaries; ethnological maps, illustrating the distribution of the varieties of man, the density of population, &c.; travel maps, showing roads or railways and ocean-routes , or designed for the special use of cyclists or aviators; statistical maps, illustrating commerce and industries; historical maps; maps specially designed for educational purposes.

In cases where the draughtsman has omitted to indicate the scale we can ascertain it by dividing the actual length of a meridian degree by the length of a degree measure upon the map. Thus a degree between 50? and 51? measures 111,226,000 mm.; on the map it is represented by 111 mm. Hence the scale is 1:1,000,000 approximately.

The linear scale of maps can obviously be used only in the case of maps covering a small area, for in the case of maps of greater extension measurements would be vitiated owing to the distortion or exaggeration inherent in all projections, not to mention the expansion or shrinking of the paper in the process of printing. As an extreme instance of the misleading character of the scale given on maps embracing a wide area we may refer to a map of a hemisphere. The scale of that map, as determined by the equator or centre meridian, we will suppose to be 1:125,000,000, while the encircling meridian indicates a scale of 1:80,000,000; and a "mean" scale, equal to the square root of the proportion which the area of the map bears to the actual area of a hemisphere, is 1:112,000,000. In adopting a scale for their maps, cartographers will do well to choose a multiple of 1000 if possible, for such a scale can claim to be international, while in planning an atlas they ought to avoid a needless multiplicity of scales.

The meridian of Greenwich has been universally accepted as the initial meridian, but in the case of most topographical maps of foreign countries local meridians are still adhered to--the more important among which are:--

Paris 2? 20? 14?? E. of Greenwich. Pulkova 30? 19? 39?? E. " Stockholm 18? 3? 30?? E. " Rome 12? 28? 40?? E. " Brussels 4? 22? 11?? E. " Madrid 3? 41? 16?? W. " Ferro 20? 0? 0?? W. of Paris.

Instead of supposing the light to fall vertically upon the surface it is often supposed to fall obliquely, generally at an angle of 45? from the upper left-hand corner. It is claimed for this method that it affords a means of giving a graphic representation of Alpine districts where other methods of shading fail. The Dufour map of Switzerland is one of the finest examples of this style of hill-shading. For use in the field, however, and for scientific work, a contoured map like Siegfried's atlas of Switzerland, or, in the case of hilly country, a map shaded on the assumption of a vertical light, will prove more useful than one of these, notwithstanding that truth to nature and artistic beauty are claimed on their behalf.

Instead of shading by lines, a like effect may be produced by mezzotint shading , and if this be combined with contour lines very satisfactory results can be achieved. If this tint be printed in grey or brown, isohypses, in black or red, show distinctly above it. The same combination is possible if hills engraved in the ordinary manner are printed in colours, as is done in an edition of the 1-inch ordnance map, with contours in red and hills hachured in brown.

The above remarks apply more particularly to topographic maps. In the case of general maps on a smaller scale, the orographic features must be generalized by a skilful draughtsman and artist. One of the best modern examples of this kind is Vogel's map of Germany, on a scale of 1:500,000.

The United States Geographic Board acts upon rules practically identical with those indicated, and compiles official lists of place-names, the use of which is binding upon government departments, but which it would hardly be wise to follow universally in the case of names of places outside America.

MEASUREMENT ON MAPS

In the formulae which follow we suppose l and l? to represent the latitudes, a and b the co-latitudes , and t the difference in longitude between them or the meridian distance, whilst D is the distance required.

If the latitudes differ, we have to solve an oblique-angled spherical triangle, of which two sides and the included angle are given. Thus,

In the above formulae our earth is assumed to be a sphere, but when calculating and reducing to the sea-level, a base-line, or the side of a primary triangulation, account must be taken of the spheroidal shape of the earth and of the elevation above the sea-level. The error due to the neglect of the former would at most amount to 1%, while a reduction to the mean level of the sea necessitates but a trifling reduction, amounting, in the case of a base-line 100,000 metres in length, measured on a plateau of 3700 metres in height, to 57 metres only.

These orthodromic distances are of course shorter than those measured along a loxodromic line, which intersects all parallels at the same angle. Thus the distance between New York and Oporto, following the former , amounts to 3000 m., while following the rhumb, as in Mercator sailing, it would amount to 3120 m.

These direct distances may of course differ widely with the distance which it is necessary to travel between two places along a road, down a winding river or a sinuous coast-line. Thus, the direct distance, as the crow flies, between Brig and the hospice of the Simplon amounts to 4.42 geogr. m. , while the distance by road measures 13.85 geogr. m. . Distances such as these can be measured only on a topographical map of a fairly large scale, for on general maps many of the details needed for that purpose can no longer be represented. Space runners for facilitating these measurements, variously known as chartometers, curvimeters, opisometers, &c., have been devised in great variety. Nearly all these instruments register the revolution of a small wheel of known circumference, which is run along the line to be measured.

The methods of producing reliefs vary according to the scale and the materials available. A simple plan is as follows--draw an outline of the country of which a map is to be produced upon a board; mark all points the altitude of which is known or can be estimated by pins or wires clipped off so as to denote the heights; mark river-courses and suitable profiles by strips of vellum and finally finish your model with the aid of a good map, in clay or wax. If contoured maps are available it is easy to build up a strata-relief, which facilitates the completion of the relief so that it shall be a fair representation of nature, which the strata-relief cannot claim to be. A pantograph armed with cutting-files which carve the relief out of a block of gypsum, was employed in 1893-1900 by C. Perron of Geneva, in producing his relief map of Switzerland on a scale of 1:100,000. After copies of such reliefs have been taken in gypsum, cement, statuary pasteboard, fossil dust mixed with vegetable oil, or some other suitable material, they are painted. If a number of copies is required it may be advisable to print a map of the country represented in colours, and either to emboss this map, backed with papier-m?ch?, or paste it upon a copy of the relief--a task of some difficulty. Relief maps are frequently objected to on account of their cost, bulk and weight, but their great use in teaching geography is undeniable.

The method of manufacturing a globe is much the same as it was at the beginning of the 16th century. A matrix of wood or iron is covered with successive layers of papers, pasted together so as to form pasteboard. The shell thus formed is then cut along the line of the intended equator into two hemispheres, they are then again glued together and made to revolve round an axis the ends of which passed through the poles and entered a metal meridian circle. The sphere is then coated with plaster or whiting, and when it has been smoothed on a lathe and dried, the lines representing meridians and parallels are drawn upon it. Finally the globe is covered with the paper gores upon which the map is drawn. The adaption of these gores to the curvature of the sphere calls for great care. Generally from 12 to 24 gores and two small segments for the polar regions printed on vellum paper are used for each globe. The method of preparing these gores was originally found empirically, but since the days of Albert D?rer it has also engaged the minds of many mathematicians, foremost among whom was Professor A. G. K?stner of G?ttingen. One of the best instructions for the manufacture of globes we owe to Altm?tter of Vienna.

Larger globes are usually on a stand the top of which supports an artificial horizon. The globe itself rotates within a metallic meridian to which its axis is attached. Other accessories are an hour-circle, around the north pole, a compass placed beneath the globe, and a flexible quadrant used for finding the distances between places. These accessories are indispensable if it be proposed to solve the problems usually propounded in books on the "use of the globes," but can be dispensed with if the globe is to serve only as a map of the world. The size of a globe is usually given in terms of its diameter. To find its scale divide the mean diameter of the earth by the diameter of the globe; to find its circumference multiply the diameter by .

For details of the various methods of reproduction see LITHOGRAPHY; PROCESS, &c.

HISTORY OF CARTOGRAPHY

A cadastral survey for purposes of taxation was already at work in Babylonia in the age of Sargon of Akkad, 3800 B.C. In the British Museum may be seen a series of clay tablets, circular in shape and dating back to 2300 or 2100 B.C., which contain surveys of lands. One of these depicts in a rough way lower Babylonia encircled by a "salt water river," Oceanus.

Anaximenes, a pupil of Anaximander, was the first to reject the view that the earth was a circular plane, but held it to be an oblong rectangle, buoyed up in the midst of the heavens by the compressed air upon which it rested. Circular maps, however, remained in the popular favour long after their erroneousness had been recognized by the learned.

Scientific geography profited largely from the labours of Eratosthenes of Cyrene, whom Ptolemy Euergetes appointed keeper of the famous library of Alexandria in 247 B.C., and died in that city in 195 B.C. He won fame as having been the first to determine the size of the earth by a scientific method. Having determined the difference of latitude between Alexandria and Syene which he erroneously believed to lie on the same meridian, and obtained the distance of those places from each other from the surveys made by Egyptian geometers, he concluded that a degree of the meridian measured 700 stadia.

This map of Eratosthenes, notwithstanding its many errors, such as the assumed connexion of the Caspian with a northern ocean and the supposition that Carthage, Sicily and Rome lay on the same meridian, enjoyed a high reputation in his day. Even Strabo adopted its main features, but while he improved the European frontier, he rejected the valuable information secured by Pytheas and retained the connexion between the Caspian and the outer ocean. In the extreme east his information extended no further than that of Eratosthenes, viz. to India and Taprobane and the Sacae .

About the same time Crates of Mallus embodied the views of the Stoic school of philosophy in a globe which has become typical as one of the insignia of royalty. On this globe an equatorial and a meridional ocean divide our earth into four quarters, each inhabited, thus anticipating the discovery of North and South America and Australia.

The period between Eratosthenes and Marinus of Tyre was one of great political importance. Carthage had been destroyed , Julius Caesar had carried on his campaign in Gaul , Egypt had been occupied , Britannia conquered , and the Roman empire had attained its greatest extent and power under the emperor Trajan . But although military operations added to our knowledge of the world, scientific cartography was utterly neglected.

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