HISTORY OF GEOGRAPHICAL THEORY Early Greek Ideas.—The earliest conceptions of the earth, like those held by primitive peoples of to-day, are difficult to discover and almost impossible to grasp. The first definite geographical theories to affect the western world were those evolved, or at least first expressed, by
Greeks. The earliest theoretical problem of geography was the form of the earth. The natural supposition that the earth is a flat disc, circular in outline, had in the time of Homer (before 90o B.c.) acquired a special definiteness by the introduction of the idea of the river Oceanus bounding the whole.
Thales of Miletus is claimed as the first exponent of the idea of a spherical earth ; but, although this does not appear to be warranted, his disciple Anaximander (c. 58o B.c.) put forward the theory that the earth had the figure of a solid body hanging freely in the centre of the hollow sphere of the starry heavens. The Pythagorean school of philosophers adopted the theory of a spherical earth, arguing that a sphere being the most perfect solid figure was the only one worthy to circumscribe the dwelling place of man. The division of the sphere into parallel zones of climate was suggested by Parmenides (c. 450 B.c.). These ideas did not influence the Ionian school of philosophers, who pre ferred to deal with facts demonstrable by travel rather than with speculations. Thus Hecataeus (c. 500 B.c.), claimed by H. F. Tozer as the father of geography on account of his general treatise on the earth, did not advance beyond the primitive con ception of a circular disc. He systematized the form of the land within the ring of ocean—the vfKw/uPVr or habitable world— by recognising two continents : Europe to the north, and Asia to the south of the midland sea. Herodotus (c. 450 B.c.) equally oblivious of the sphere, criticized and ridiculed the circular out line of the oiKoVµFPM which he held to be longer from east to west than it was broad from north to south (hence the modern designation of longitude and latitude), and he divided the land into three continents—Europe, Asia and Africa. Beyond the limits of his personal travels Herodotus applied the character istically Greek theory of symmetry to complete, in the unknown, outlines of lands and rivers analogous to those which had been explored. Symmetry was in fact the first geographical theory, and the effect of Herodotus's hypothesis that the Nile must flow from west to east before turning north in order to balance the Danube running from west to east before turning south, lingered in the maps of Africa down to the time of Mungo Park.
Aristotle (384-322 B.c.) must be given the distinction of found ing scientific geography. He demonstrated the sphericity of the earth by three arguments : (1) that the earth must be spherical, because of the tendency of matter to fall together towards a common centre: (2) that only a sphere could always throw a circular shadow on the moon during an eclipse: and (3) that the shifting of the horizon and the appearance of new constellations, or the disappearance of familiar stars, as one travelled from north to south, could only be explained on the hypothesis that the earth was a sphere. Parmenides had pictured a torrid zone uninhabitable by reason of heat, two frigid zones uninhabitable by reason of cold, and two intermediate temperate zones fit for human occupation, but Aristotle was the first of the philosophers who defined the temperate zone as extending from the tropic to the Arctic circle.
The fitting of the oiKovi vj to the sphere was the second theoretical problem of geography. Aristotle was inclined to view the habitable world as a very long and relatively narrow band almost encircling the globe in the north temperate zone, but his argument as to the narrowness of the sea between West Africa and East Asia from the occurrence of elephants at both extrem ities, is difficult to understand.
The word geography did not appear before Aristotle and he may have used it, but H. Berger considers that the expression was introduced by Eratosthenes. Aristotle was certainly conversant with many facts, such as the formation of deltas, coast-erosion, and to a certain extent the dependence of plants and animals on their physical surroundings. He formed a comprehensive theory of the variations of climate with latitude and season, and was convinced of the necessity of a circulation of water between the sea and rivers, though, like Plato, he held that this took place by water rising from the sea through crevices in the rocks, losing its dissolved salts in the process. He speculated on the differences in the character of races of mankind living in different climates and correlated the political forms of communities with their situation on a seashore, or in the neighbourhood of natural strongholds.
Pythagoras (c. S3o B.c.) had speculated as to the existence of antipodes, and when the first approximately accurate measurement of the globe and estimates of the length and breadth of the olrcov,uvrl were made by Eratos thenes (c. 250 B.C.) the fact that, as then known, the habitable world occupied less than a quarter of the surface of the sphere was clearly recognised. It was natural, if not strictly logical, that the river Oceanus should be extended from a narrow stream to a world-embracing sea, and here again Greek theory, or rather fancy, gave its modern name to the greatest feature of the globe. The old instinctive idea of symmetry probably led the Stoic philosophers represented by Crates of Mallus (c. 15o B.c.) to place an oiKou,c4v) in each quarter of the sphere in order to satisfy the love of nature for life; the three unknown world islands being those of Antoeci, Perioeci and Antipodes. This was a theory not only attractive to the philosophical mind, but eminently adapted to promote exploration. It had its opponents, however, for Herodotus had shown that sea-basins like the Caspian existed cut off from the ocean, and it is still a matter of controversy how far the pre-Ptolemaic geographers believed in a water-connection between the Atlantic and the Indian oceans.
Strabo (5o B.C.—A.D. 24) followed Eratosthenes rather than Aristotle, but with sympathies which went out more to the human interests than to the mathematical basis of geography. He compiled a very remarkable work dealing, in large measure from personal travel, with the countries sur rounding the Mediterranean. He may be said to have set the pattern which was followed in succeeding ages by the compilers of "political geographies." Pomponius Mela (c. A.D. 40), follow ing Strabo, held that the southern temperate zone contained a habitable land, which he designated by the name Antichthones. Claudius Ptolemaeus (c. A.D. 15o), concentrated in his writings the final outcome of all Greek geographical learning and passed it across the gulf of the middle ages by the hands of the Arabs, to form the starting point of the science in modern times. His geography was based broadly on the work of his predecessor, Marinus of Tyre, and on that of Hipparchus, the follower and critic of Eratosthenes. It was the ambition of Ptolemy to describe and represent accurately the surface of the oiKov,u r/, for which purpose he took immense trouble to collect all existing astronom ical determinations of the latitude of places, all estimates of longitude, and to make every possible rectification of distances by land or sea. His work was mainly cartographical in its aim, and theory was as far as possible excluded. The symmetrically placed hypothetical islands in the great continuous ocean dis appeared and the oiicovuivr/ acquired a new form by the repre sentation of the Indian ocean as a larger Mediterranean com pletely cut off by land from the Atlantic. The terra incognita uniting Africa and Farther Asia was an unfortunate hypothesis which discouraged exploration. Ptolemy used the word geography to signify the description of the whole
on mathe matical principles, while chorography signified the fuller descrip tion of a particular region, and topography the very detailed description of a smaller locality. The Caliph al-Mamun (c. A.D.
the son and successor of Harun al-Rashid, caused an Arabic version of Ptolemy's great astronomical work to be made, which is known as the Almagest. The geography of Ptolemy was also known and is constantly referred to by Arab writers. The Arab astronomers measured a degree on the plains of Mesopo tamia, thereby deducing a fair approximation to the size of the earth, and the caliph's librarian, Abu Jafar Muhammad ben Musa, wrote a geographical work, now unfortunately lost, com posed on the model of that of Ptolemy.
The Middle Ages saw geographical know ledge die out in Christendom, although it retained a certain vitality in Islam. The verbal interpretation of scripture led Lactantius (c. A.D. 320) and other ecclesiastics to denounce the spherical theory of the earth as heretical, and as all learning was confined to the church, Greek science gave place to primitive ignorance as shown in the monkish wheel-maps. The journey of Marco Polo, the increasing trade with the east and the voyages of the Arabs in the Indian Ocean prepared the way for the reacceptance of Ptolemy's ideas even amongst churchmen when the sealed books of the Greek original were translated into Latin by Angelus in 1410.
The old arguments of Aristotle and the old measurements of Ptolemy were used by Toscanelli and Columbus in urging a westward voyage to India and mainly on this account did the crossing of the Atlantic rank higher in the history of scientific geography than the laborious feeling out of the coast line of Africa. But not until the voyage of Magellan shook the scales from the eyes of Europe did modern geography begin to advance. Discovery had outrun theory; the rush of new facts made Ptolemy practically obsolete in a generation.
The earliest evidence of the reincarnation of a sound theoretical geography is to be found in the text-books by Peter Apian and Sebastian Munster. Apian in his Cosmographicus Tiber, published in 1524 and subsequently edited and added to by Gemma Frisius under the title of Cosmographia, based the whole science on mathe matics and measurement. He followed Ptolemy closely, enlarging on his distinction between geography and chorography. This slen der distinction was made much of by most subsequent writers until Nathanael Carpenter in 1625 pointed out that the difference was simply one of degree, not of kind. Sebastian Munster, on the other hand, in his Cosmographia universalis of 1544, paid no regard to the mathematical basis of geography, but following the model of Strabo, described the world according to its different political divisions, and entered with great zest into the question of the productions of countries, and into the manners and cos tumes of the various peoples. Thus early began the separation between mathematical and political geography.
Throughout the 16th and 17th centuries the rapidly accumulating store of facts as to the extent, outline and mountain and river systems of the lands of the earth were put in order by the generation of cartographers of whom Mercator was the chief ; but the writings of Apian and Munster held the field for a hundred years without a serious rival. Mean while the new facts were the subject of original study by philos ophers and by practical men without reference to classical tra ditions. Bacon argued keenly on geographical matters and was a lover of maps.
Philip Cluver's Introductio in geographiam universam tam veteresn quarn novam was published in 1624. Geography he de fined as "the description of the whole earth, so far as it is known to us." It is distinguished from cosmography by dealing with the earth alone, not with the universe, and from chorography and topography by dealing with the whole earth, not with a coun try or a place. The first book, of fourteen short chapters, is con cerned with the general properties of the globe; the remaining six books treat in considerable detail of the countries of Europe and of the other continents. Each country is described with par ticular regard to its people as well as to its surface.
In 1625 Nathanael Carpenter, Fellow of Exeter College, Oxford, published a little book, Geographie delineated forth in Two Bookes, containing the Spherical! and Topical! parts thereof. It is discur sive in its style and verbose ; but it is remarkable for the strong common sense displayed by the author, his comparative freedom from prejudice, and his firm application of the methods of scien tific reasoning to the interpretation of phenomena. Basing his work on the principles of Ptolemy, he brings together illustrations from the most recent travellers, and does not hesitate to take as illus trative examples, the familiar city of Oxford and his native county of Devon. He divides geography into The Spherical Part, or that for the study of which mathematics alone is required, and The Topical Part, or the description of the physical relations of parts of the earth's surface, preferring this division to that favoured by the ancient geographers into general and special.
A much more important work in the history of geographical method is the Geographia generalis of Bernhard Varenius, a German medical doctor of Leyden, who died at the age of twenty-eight in 165o, the year of the publication of his book. Although for a time it was lost sight of on the continent, Sir Isaac Newton thought so highly of this book that he prepared an annotated Latin edition which was published in Cambridge in 1672, with the addition of the plates which had been planned by Varenius, but not produced by the original publishers. Dug dale in his English translation (1733) says "The reason why this great man took so much care in correcting and publishing our author, was because he thought him necessary to be read by his audience, the young gentlemen of Cambridge, while he was deliver ing lectures on the same subject from the Lucasian Chair." The treatise of Varenius is a model of logical arrangement and terse expression; it is a work of science and of genius; one of the few of that age which can still be studied with profit. The English translation renders the definition thus : "Geography is that part of mixed mathematics which explains the state of the earth and of its parts, depending on quantity, viz., its figure, place, magni tude and motion, with the celestial appearances, etc. By some it is taken in too limited a sense, for a bare description of the several countries; and by others too extensively who along with such a description would have their political constitution." But Varen ius, though he was reluctant to include the human side of geog raphy in his system, allowed it as a concession to custom. His divi sion of geography was into (1) General or universal, dealing with the earth in general, and explaining its properties without regard to particular countries; and (2) Special or particular, dealing with each country in turn from the chorographical or topographical point of view. General geography was divided into—(1) the absolute part, dealing with the form, dimensions, position and sub stance of the earth, the distribution of land and water, mountains, woods and deserts, hydrography (including all the waters of the earth) and the atmosphere; (2) the relative part, including the celestial properties, i.e., latitude, climate, zones, longitude, etc.; and (3) the comparative part, which "considers the particulars arising from comparing one part with another" ; but under this head the questions discussed were longitude, the situation and distances of places, and navigation. Varenius does not treat of special geography, but gives a scheme for it under three heads— terrestrial, celestial, human. This system of geography founded a new era, and the book was the unchallenged standard for more than a century.
The next marked advance in the theory of geography was made nearly simultaneously by the studies of the Swedish chemist, Torbern Bergman, acting under the impulse of Linnaeus, and by those of the German philoso pher, Immanuel Kant. Bergman's Physical Description of the Earth was published in Swedish in 1766, and translated into Eng lish in 1772 and into German in 1774. It is a plain, straig',ht forward description of the globe, and of the various phenomena of the surface, dealing only with definitely ascertained facts in the natural order of their relationships, but avoiding any systematic classification or even definitions of terms.
The problems of geography had been lightened by the de structive criticism of the French cartographer D'Anville, who had purged the map of the world of the last remnants of unverified tradition, and rendered it richer by the dawn of the new era of scientific travel, when Kant brought his logical powers to bear upon them. Kant's lectures on physical geography were delivered in the university of Konigsberg from 1765 onwards. Geography appealed to him as a valuable educational discipline, the joint foun dation with anthropology of that "knowledge of the world" which was the result of reason and experience. In this connection he divided the communication of experience from one person to another into two categories—the narrative or historical and the descriptive or geographical ; both history and geography being viewed as descriptions, the former in order of time, the latter in order of space. Physical geography he viewed as a summary of nature, the basis not only of history but also of "all the other possible geographies," of which he enumerates five, viz., (1) Mathematical geography, which deals with the form, size and movements of the earth and its place in the solar system; (2) Moral geography, or an account of the different customs and characters of mankind according to the region they inhabit ; (3 ) Political geography, the divisions according to their organized governments; (4) Mercantile geography, dealing with the trade in the surplus products of countries; (5) Theological geography, or the distribution of religions. Here there is a clear and formal statement of the interaction and causal relation of all the phe nomena of distribution on the earth's surface, including the in fluence of physical geography upon the various activities of man kind from the lowest to the highest. Notwithstanding the form of this classification Kant himself treats mathematical geography as preliminary to, and therefore not dependent on, physical geography. Physical geography itself is divided into two parts : general, which has to do with the earth and all that belongs to it —water, air and land; and particular, which deals with special products of the earth—mankind, animals, plants and minerals.
Alexander von Humboldt (1769 1859) was the first modern geographer to become a great traveller. The impulse given to the study of natural history by the example of Linnaeus, the results brought back by Banks, Solander and the two Forsters, who accompanied Cook in his voyages of dis covery, the studies of De Saussure in the Alps, and the lists of desiderata in physical geography drawn up by that investigator, combined to prepare the way for Humboldt who advanced the theory of geography mainly by his insistence on the great prin ciple of the unity of nature. In his Cosmos and other works he brought all the "observable things" which the eager collectors of the previous century had been heaping together regardless of order or system, into relation with the vertical relief and the horizontal forms of the earth's surface. Thus he demonstrated that the forms of the land exercise a directive and determining influence on climate, plant life, animal life and on man himself. The idea was not new for Kant himself had given it full expression, but Humboldt's concrete illustrations and the remarkable power of his personality enabled him to enforce these principles with im mediate and lasting effect. The treatises on physical geography by Mary Somerville and John Herschel fully showed the effect produced in Great Britain by the stimulus of Humboldt's work. Humboldt's contemporary, Carl Ritter (1779-1859) ex tended and disseminated the same views, and in his interpretation of "Comparative Geography" he laid stress on the importance of forming conclusions, not from the study of one region by it self, but from the comparison of the phenomena of many places. Impressed by the influence of terrestrial relief and climate on human movements, Ritter was led deeper and deeper into the study of history and archaeology. His monumental Vergleichende Geographie, which was to have made the world its theme, died out in a wilderness of detail in twenty-one volumes bef ore it had covered more of the earth's surface than Asia and a portion of Africa.
During the rapid development of physical geography many branches of the study of nature, which had been included in the cosmography of the early writers, the physiography of Lin naeus and even the Erdkunde of Ritter, had been so much ad vanced by the labours of specialists that their connection was apt to be forgotten. The science of geography, passed on from antiquity by Ptolemy, re-established by Varenius and Newton, and systematized by Kant, included within itself definite aspects of all those terrestrial phenomena which are now treated exhaus tively under the heads of geology, meteorology, oceanography and anthropology; and the inclusion of the requisite portions of per fected results of these sciences in geography is simply the gather ing in of fruit matured from the seed scattered by geography it self. The study of geography was advanced by improvements in cartography, not only in the methods of survey and projec tion, but in the repiesentation of the third dimension by means of contour lines introduced by Philippe Buache in 1737, and the more remarkable because less obvious invention of isotherms introduced by Humboldt in 1 817 .
Teleology or the argument from design had been a favourite form of reasoning among Christian theolo gians and, as worked out by Paley in his Natural Theology, it served the useful purpose of emphasizing the fitness which exists between all the inhabitants of the earth and their physical environ ment. It was held that the earth had been created so as to fit the wants of man in every particular. This argument was tacitly accepted or explicitly avowed by almost every writer on the theory of geography, and Carl Ritter distinctly recognized and adopted it as the unifying principle of his system. As a student of nature, however, he did not fail to see, and as a professor of geography he always taught, that man was in very large measure conditioned by his physical environment.
The evolutionary theory, more than hinted at in Kant's "Physi cal Geography" and worked out by the researches of Charles Darwin, Alfred Russel Wallace and Joseph Dalton Hooker, from their observations as travelling naturalists, has become the unify ing principle in geography. The conception of the development of the plan of the earth from the first cooling of the surface of the planet throughout the long geological periods, the guiding power of environment on the circulation of water and of air, on the distribution of plants and animals, and finally on the move ments of man, give to geography a philosophical dignity and a scientific completeness which it never previously possessed. The influence of environment on the organism may not be quite so potent as it was believed to be, in the writings of Henry Thomas Buckle for instance, and certainly man, the ultimate term in the series, reacts upon and greatly modifies his environment ; yet the fact that environment does influence all distributions is established so that it cannot be moved. In this way also the position of geography, at the point where physical science meets and mingles with mental science is explained and justified. The change which took place during the 19th century in the substance and style of geography may be well seen by comparing the eight volumes of Malte-Brun's Geographic universelle (Paris, 1812 1829) with the twenty-one volumes of Elisee Reclus's Geographie Universelle (Paris, 1876-1895) and the new and larger edition planned by Vidal de la Blache as the work of many authors in cluding A. Demangeon and Pierre Denis, shows that development is still going on. It has been usual to assign to Oscar Peschel (1826-1875) the credit of having corrected the preponderance which Ritter gave to the historical element, and of restoring physical geography to its old pre-eminence. As a matter of fact, each of the leading modern exponents of geography—such as Ferdinand von Richthofen, Hermann Wagner, Friedrich Ratzel, William M. Davis, Albrecht Penck, A. de Lapparent, Elisee Reclus, E. de Martonne, G. G. Chisholm, Halford Mackinder and Ellsworth Huntington, has his individual point of view.
The theory of geography devel oped by a series of efforts to cope with accumulations of new facts of discovery. In the earlier centuries a traveller required little more than sound health and adventurous spirit to enable him to make discoveries which have crowned his name for all time ; but in the twentieth century this is no longer the case. In order to discover facts of importance the traveller must now be him self a geographer grounded in the principles of the science which have crystallized out of the labours of the past. Extensive wander ings have given place to intensive studies and wisely-directed researches. The elementary teacher of geography can no longer be content to repeat lists of features and haphazard remarks as to notable things; but must have a foundation of systematic knowledge. This was not generally realized until the nineteenth century was near its end. Professors of geography had indeed existed for many years in Germany, France and some other con tinental countries, but they lectured to few students, and it was only in the last decade after great advances had been made in continental universities that the universities of Great Britain and the United States admitted geography into their curricula. In 1892 the efforts of Douglas Freshfield through the Royal Geo graphical Society secured the appointment of lecturers on geog raphy in Oxford and Cambridge. Progress in the development of a school of geography in these universities has been steady and in each there are now several instructors on the subject under a Reader preparing students for a Geographical Tripos awarding Honours degrees. The four universities of Scotland, most of the constituent colleges of the University of London, the newer pro vincial English universities and the University of Wales have appointed Professors or Readers of geography who, despite (1928) the financial difficulties, endeavour to develop interest of a high order. The United States had three professors of geography in 189 i : W. M. Davis at Harvard, R. F. Tarr at Cornell and W. Libbey at Princeton ; by their efforts, and especially by the bril liant work of Davis, a demand was created for trained geography teachers which led to immense development. In 1924 there were fully equipped departments of geography, several of them with i s or more instructors, in the universities of California, Chicago, Clark (at Worcester, Mass.), Michigan (Ann Arbor), Ohio, State and Ohio (Athens), while fifty other universities had less com plete equipment, and, in all, university instruction in geography was being given to 14,000 students annually.
