THE DARK AGE
From this point it becomes necessary to vary the treatment of our
subject hitherto followed. With the breakup of the Roman Empire and
the establishment of Christianity the old learning was obliterated.
Religion became the central fact of intellectual exercise, and, except
in so far as Christian doctrine and Holy Scripture involved reference
to natural phenomena, every branch of natural science was withered by
the breath of theology. The first serious assaults of the barbarian
invader were made on the frontiers of the Roman Empire in the fourth
century A.D.; in 330 the seat of government was transferred from Rome
to Byzantium, and at the close of the century the empire was divided
into eastern and western parts. It has often been pointed out that
these events did more than mark the beginning of the disruption of
the Roman Empire; they also mark the parting of the ways of eastern
and western European religion and culture. In the west it became
the function of Christianity to teach and civilize peoples untaught
and uncivilized; but, limited and intolerant as was its outlook
upon natural science generally, it discarded the learning of the
pre-Christian era. We have now to inquire how geography was affected by
this attitude towards secular learning.
It is true that the habit of travel, so far from being forgotten, was
even fostered by missionary work and the practice of pilgrimage.
Again, opportunities for the extension of geographical knowledge were
provided by various episodes in the history of the centuries with
which we are now concerned; thus Procopius, the historian of the
Persian, Vandal, and Gothic wars of the epoch of the Roman (Byzantine)
emperor Justinian in the sixth century, had ample opportunities for
geographical description and used them well. Justinian even despatched
an expedition to China (which returned thence). But the geographical
theorists of the period now under review had little if any concern with
contemporary travellers’ results.
The Christian cosmographers, having found in a spiritual sense a new
heaven and a new earth, were at pains to create them in a scientific
sense also. It was their aim to reconcile geographical theory with
the literal sense of Holy Scripture, and they were not only unable
to explain, but were (for the most part) willing to disprove,
pre-Christian theory by that light. Thus Lactantius Firmianus (_c._
260–340), becoming converted, denied the possibility of the sphericity
of the earth or the existence of antipodes. On the other hand, this
conception died hard, for it was maintained by pagan writers at this
time--as, for instance, Martianus Capella, who, writing in the third or
fourth century, followed such authorities as Ptolemy and Pythagoras.
And these pre-Christian views must have caused some of the Christian
authors to doubt, for they left unsettled such questions as that of the
earth’s shape, on the plea that they formed no part of the Christian
doctrine; an instance of this attitude is provided by St. Basil the
Great of Cæsarea (_c._ 330–379) in his treatise on the Hexaemeron (Six
Days of the Creation).
[Illustration: Fig. 5.--The World according to Cosmas Indicopleustes.]
One of the principal popular attractions of geography has always
been its function of describing the wonders of distant lands, and in
Julius Solinus Polyhistor (probably of the third century) we have a
typical geographer of the marvellous, who in his _Collectanea Rerum
Memorabilium_ drew upon Pliny, Pomponius Mela, and many earlier authors
for a description of the wonders of the world, and became himself
regarded as a high authority. With such influences at work on the study
of geography, the genesis of the theories of Cosmas Indicopleustes
becomes perhaps less surprising than the theories themselves. He was a
merchant of Alexandria, and a traveller (as his surname is inaccurately
intended to record) in the Red Sea and the ocean beyond, who, thus
fortified in geographical study, became a monk and wrote his _Christian
Topography_ about the middle of the sixth century, in opposition to
the pre-Christian theories. Under his pen the inhabited earth became
a flat, rectangular oblong surrounded by oceans. At the north is a
conical mountain round which the sun (which is some forty miles in
diameter and at no great distance from the earth) revolves, passing
about the summit in summer, so that it is hidden from the earth for
a shorter time daily than in the winter, when it passes about the
base. Again, in such conditions as have been indicated, it is at least
intelligible that a responsible writer should accept a mountain 250
miles high, as is stated of Mount Pelion by Dicuil, an Irish monastic
scholar who completed his _De Mensura Orbis Terræ_ in 825. He, however,
was little else than a compiler, and in the manner of his kind made
an ill choice of sources. Among them, however, he refers to surveys
made by Julius Cæsar, Augustus, and one of the emperors Theodosius;
the originals thus referred to are unknown. To mention the various
Churchmen and others who, though in no sense geographers, were expected
to deal with the theories of the earth and the universe in connection
with their religious doctrines, would make but a tedious list.
The view of the sphericity of the earth was not wholly lost.
Certain expressions of the Venerable Bede (_c._ 672–735), even if
he did not specifically formulate the theory, were capable of that
construction, although in 741 we find Virgilius, the Irish bishop of
Salzburg, attacked by the Pope for his assertion of the existence of
antipodes (or at least an assertion that may bear that construction).
Nevertheless, these theories made headway, and from the eleventh
century they became more and more acceptable to leaders of learning.
Adam of Bremen accepted them; he is also an important figure in
other departments of geography. He flourished in the second half of
the eleventh century; his history is a specially valuable authority
for the Baltic lands and other parts of Scandinavia and Russia. Its
fourth book is a _Descriptio Insularum Aquilonis_, for which there was
no little material, for not only had holy men from Ireland visited
the Orkneys, Shetlands, Faeröe, and Iceland in the sixth and seventh
centuries, but the Norsemen had entered upon their period of colonizing
activity; besides Great Britain and Ireland they had reached Iceland
in 874, Greenland a century later, and Vinland in 1000; and this last,
that much-debated[3] landfall situated somewhere on the North American
coast south-west of Greenland, is first mentioned by Adam of Bremen. A
similar appreciation of north European geography had been shown by King
Alfred the Great, who in translating (and freely editing) earlier works
had introduced much of the knowledge acquired down to his own time.
[3] Not only so in modern times; at least one Scandinavian
geographer, of the end of the thirteenth century, was
prepared to recognize it as belonging to Africa.
[Illustration: Fig. 6.--Beatus’s Map.]
Monastic cartography did not keep pace with theory. The disputed
habitable land beyond the confines of the known world, and separated
from it by the impassable torrid zone (a classical conception),
appeared in maps of the seventh and eighth centuries. Apart from this
(and it came to be generally admitted) we have rectangular oblong maps
like that of Cosmas, and circular maps, out of which was evolved the
diagrammatic form of a =T= within an =O=, where the =T= represented
the Mediterranean, the Tanais, and the Nile, its upright showing the
westward extension of the sea, and the cross-stroke the two rivers,
to left and right respectively, so that the west was at the bottom
of the map. Europe lay within the left-hand angle of the =T=, Africa
in the right-hand angle; Asia was the half circle above it. The holy
city of Jerusalem lay “in the midst of the nations.” Some maps, again,
gave the earth an oval form. In all, the habitable earth was still
surrounded by ocean. In the far east sometimes appeared Paradise.
This feature and the unknown habitable world above mentioned were
both shown in the map of Beatus, a Spanish priest (_c._ 730–798), who
illustrated his _Commentaria in Apocalypsin_ with one of the earliest
known Christian maps of the world, several copies of which, dating from
the tenth to the thirteenth centuries, are preserved. In this map the
“known” habitable world appears as a dome-shaped mass with its flat
base to the south, forming the northern shore of a strait separating
it from the unknown southern land. The known world is broken for more
than half its breadth by the vast gulf of the Mediterranean, which
has two great arms reaching far northward; the Caspian Sea is a gulf
opening into the north-east part of the circumfluent ocean, in which
are set islands in an orderly ring all round the world; all sense of
direction in the flow of rivers is awry, and topographical accuracy is,
of course, entirely wanting.
What early Christianity lost by looking askance at classical theory
the Arabs, after the establishment of Muhammadan power in the seventh
century, in great measure gained, for they were free of scruple as
regarded the earlier learning, and eager for knowledge. Early in the
ninth century the Caliph Al-Mamun of Bagdad gave a strong impulse to
geographical and kindred studies. He caused translations to be made of
Ptolemy’s astronomical and geographical works, and of those of other
ancient authorities, among whom was Marinus of Tyre. Muhammad ben
Musa, librarian of Bagdad, compiled a _Description of the World_, or
gazetteer of place-names with their positions, on the Ptolemaic model.
Degrees were measured in Syria and Mesopotamia. Among Arab descriptive
works the first which survives is that of Suleiman, a merchant, who
made voyages to India and China in the middle of the ninth century. In
the first half of the following century Masudi travelled widely--to
India and Ceylon, probably to China, to Madagascar, to the Caspian,
and in Syria and Egypt. His work, the _Meadows of Gold and Mines of
Precious Stones_, is an example of the application of the results of
travel and personal observation to history; he was commonly compared
with Pliny. The Muhammadan demand for geographical works at this period
appears to have been great, from the fact that Abu Zaid’s work, written
about 921, was revised thirty years later by Istakhri, who travelled
all through the Muhammadan lands, in his _Book of Climates_ (or Zones);
and this was again revised and extended by Ibn Haukal in 977 in his
_Book of Roads and Kingdoms_.
A more important figure is Idrisi (_c._ 1099–1154), an Arab of Spanish
birth, who was probably educated at the great centre of learning,
Cordova. He travelled in North Africa and Asia Minor, and, settling
in Sicily, made a celestial sphere and a map of the world in silver
for King Roger II. Idrisi conceived a substitute for a projection by
dividing the inhabited world into seven climates or zones between the
equatorial line and the arctic region; each of these was divided into
eleven equal parts by perpendicular lines. The squares thus formed
were used (to the disregard of natural or political divisions) in a
description of the earth carried out by Idrisi for the king, which is
noteworthy as having been put together, at least in part, from the
reports of an organized system of observers, who were despatched at
Roger’s order to various countries. Arabian cartography, however, so
far as is known, was primitive. Yet the Arab astronomers made some
close meridianal determinations--an error of only three degrees between
Toledo and Bagdad, for example, and a calculation of the major axis of
the Mediterranean which was very near the truth.
Before leaving this period it is worth remarking how commercial
activity had not only developed within, but had circumscribed the
European area. The Arabs, penetrating eastward into Asia, came in
contact with traders from north and western Europe using a route which,
from the eighth century, passed “from India through Novgorod to the
Baltic; and Arab coins found in Sweden prove how closely the enterprise
of the Arabs and the Northmen intertwined” (H. R. Mill). Thus ways were
prepared for the advancement of geographical knowledge when the science
should emerge from its stagnation.