ArticlePDF Available

Eratosthenes’ map of the oecumene

Authors:

Abstract and Figures

Eratosthenes (circa 276 B.C.–194 B.C.) is considered a famous scientist of ancient Greece. He was a mathematician and geographer. Born in Cyrene, now Shahhat (Libya), he was appointed to teach the son of the Egyptian King Ptolemy III Euergetes. In 240 B.C., he became the third chief librarian the Great Library of Alexandria. Eratosthenes laid basics for mathematical geography. He was the first to calculate precisely in an original way the Earth meridian's length between Syene and Alexandria. For this purpose he used perpendicular projection of the sun rays during summer solstice (06.22) near the town Syene, now Aswan. His estimation of the length of the Earth's radius (6300 km) is close to present estimation (6371 km). He calculated that a year possesses 365.25 days. He also emphasized the significance of maps as the most important thing in geography. Eratosthenes was the first one to use the term “geographem” to describe the Earth. In this way he legitimized the term of geography. He also put into system geographical information from various sources in order to obtain a map of the world as precise as possible.
Content may be subject to copyright.
81
Copyright © 2012 Vilnius Gediminas Technical University (VGTU) Press Technika
http://www.tandfonline.com/TGAC
GEODESY AND CARTOGRAPHY
ISSN 2029-6991 print / ISSN 2029-7009 online
2012 Volume 382: 8185
doi:10.3846/20296991.2012.695332
UDK 528.9
ERATOSTHENES’ MAP OF THE OECUMENE
Viktoras Lukoševičius1, Tomas Duksa2
1Technology Faculty, Šiauliai University, Vilniaus g. 141, LT-76353 Šiauliai, Lithuania
2Lithuanian Cartographic Society, M. K. Čiurlionio g. 21/27, LT-03101 Vilnius, Lithuania
E-mails: 1vikluko@kava.lt (corresponding author); 2t.duksa@gmail.com
Received 26 April 2012; accepted 21 June 2012
Abstract. Eratosthenes (circa 276 B.C.–194 B.C.) is considered a famous scientist of ancient Greece. He was a
mathematician and geographer. Born in Cyrene, now Shahhat (Libya), he was appointed to teach the son of the
Egyptian King Ptolemy III Euergetes. In 240 B.C., he became the third chief librarian the Great Library of Alexan-
dria. Eratosthenes laid basics for mathematical geography. He was the rst to calculate precisely in an original way
the Earth meridian’s length between Syene and Alexandria. For this purpose he used perpendicular projection of
the sun rays during summer solstice (06.22) near the town Syene, now Aswan. His estimation of the length of the
Earth’s radius (6300 km) is close to present estimation (6371 km). He calculated that a year possesses 365.25 days.
He also emphasized the signicance of maps as the most important thing in geography. Eratosthenes was the rst
one to use the term “geographem” to describe the Earth. In this way he legitimized the term of geography. He also
put into system geographical information from various sources in order to obtain a map of the world as precise as
possible.
Keywords: ancient geography, Eratosthenes, maps design, stadia, meridian, parallel, Balts.
1. Introduction
It was Alexandria which took the leading position in science
from Athens since the middle of the third century before
Christ. In 332 B.C. Alexandria was founded in the former
Egyptian settlement Rhacotis by Alexander Macedonian;
the town was named in the founder’s honour. e town
served as a placement of Alexander the Great sarcopha-
gus. During the reign of Ptolemaic dynasty (305–30 B.C.)
Alexandria was the capital city of Egypt and since 200 B.C.
the town was the capital of Hellenistic world of science
with famous museums, university and library. Scien-
tists here were highly appreciated. In 280 B.C. a special
town for the scientists called Mouseion (patronized by
the Muses) was established: it included science academy
with half a million manuscripts in the library and astro-
nomic observatory. e library of Alexandria is consid-
ered to be the oldest in the world and includes treasury of
civilization, the centre of science, art, dierent religions,
languages and cultures. Here well-known philosophers
and scientists were working, Euclid, the founder of the
fundamentals of geometry and Archimedes, developer of
the fundamentals of hydrostatics (Archimedes law). Cir-
ca 100 A.D. the Old Testament was translated into Greek
and called Septuagint (Teeple 2002).
Alexandria was also famous for one of the Seven
Wonders of the World – the Pharos Lighthouse, which
according to veried data was 134 meters high. It was
erected in 280 B.C. during the reign of Ptolemy II. It was
the rst lighthouse in the world and nearly the only one
on Earth as it had copper mirrors, reecting re ames.
e lighthouse made of white marble had 3 cascades; its
peak was decorated with a bronze sculpture, its light be-
ing visible 50 km away. In 14th c. i.e. in 1303 and 1323
it suered from the earthquakes and was ruined. So, it
resulted in standing for about 1500 years. At that time
the lighthouse was one of the highest buildings on Earth
surpassed only by the pyramids of Giza (Fig. 1). Its im-
age was used on the coins of those times. e majority of
towns, founded by Alexander Macedonian disappeared,
however Alexandria has remained up to the present. e
lighthouse was completely destroyed in 1480 by Egyptian
sultan of Mamelukes Quaitbay, who used the ruins of the
lighthouse to build defensive forts of Alexandria.
Great mathematicians of Alexandria were generally
interested in geometry and astronomy. e movement
of stars and the Sun was used for positioning the Earth.
Alexandria had the most famous school of geographers,
among them were known for their works Aristarchus
(310–250 B.C.), the founder of the theory of analogy,
Hipparchus (160–125 B.C.), the founder of astrolabe,
Strabon (Strabo) (60 B.C.–20 A.D.), the author of “His-
tory” and “Geography” and Cl. Ptolemy (100–178 A.D.),
predecessor of the Renaissance of cartography (Kudaba
1980).
REVIEW
82 V. Lukoševičius, T. Duksa. Eratosthenes’ map of the oecumene
2. Dicaearchus’ map
Eratosthenes chose for essential improvement the most
precise known map of oecumene (inhabited territories)
devised by Aristotle’s pupil Dicaearchus of Messina (345–
285 B.C.) (Fig. 2). Dicaearchus having used geographical
discoveries and taking into account the descriptions by
the traveller Pytheas named in his map Europe, Libya
(Libye), Arabia (Arabes), Persia (Perse), India (Indiens)
and Sri Lanka (Tapr o b a n e ). Besides the Atlantic Ocean
(Atlantique) he also named the Black Sea (Pont Euxin),
the Caspian Sea (M. Hyreanienne), the Mediterranean
Sea (Mer Interieure), the Red Sea (G. Arabique) and the
Arabian Sea (Mer Erythree). e map also included best
known rivers, such as the Nile (Nil), the Indus (Indus),
the Ganges (Ganges), the Syr Darya (Jaxartes), and the
Amu Darya (Oxus). e map also named and marked
towns, nowadays considered as historical, such as Gades
(Cadiz), Carthage, Memphis, Ty r (Saida), ebes, Ba-
bilone (Babylon), and Suses (Susa). According to geog-
raphy historians, the map presents quite precisely West
European coastline as well as both geographical position
and islands conguration of the British Islands (Samas
1997).
Dicaearchus was the rst one to use mean paral-
lel and mean meridian in his map. He drew them across
Rhode Island in the Mediterranean Sea. e Island at
that time was considered to be Helios, the Suns God
cult centre. e Island was chosen most likely because of
the Rhodes Colossus (e Sun’s God Helios’s 36 m high
sculpture, created in the second century B.C.), which was
famous as one of the wonders of the world.
3. Eratosthenes’ map
e information about the maps, devised by Erato-
sthenes, reached the modern world only due to the writ-
ings of Strabon (68 B.C.–19 A.D.) and Cleomen. Erato-
sthenes handed the Royal palace of Egypt a world map
which had been devised trying to keep the selected scale
using rectangular projection, where the world had been
pressed to the point so that its parallels and meridians
made perpendicular angles (Harwood 2008).
Eratosthenes, as well as previous geographers, drew
a right line, called diaphragm, across the Strait of Gi-
braltar, the Strait of Messina, Rhode Island and Taurus
Mountains up to the very end of the oecumene in the
East (Chomskis 1979). Eratosthenes, treating Rhode Is-
land as the crossroads of mean parallel and mean merid-
ian, in his map additionally drew 10 parallels and 11 me-
ridians across the local objects, set by measurements. In
this way he received a geographical grid. It later served
as a basis to use cylindrical cartographical projection.
Both parallels and meridians have their own names aer
the corresponding local objects. Next to the grid there
are line values in stadia (1 stadium is about 0.152 km).
ey stretch from the equator and from the very west-
ern meridian in the Ethiopian Ocean (Ocean Ethiopien).
In Dicaearchus’ of Messina map the same ocean is called
Atlantic Ocean (Atlantique). e map has a notice in the
SW corner that every degree starting from the equator
consists of 700 stadia.
Eratosthenes’s map, devised in 220 B.C., depicts the
centre of civilization of that time (the Mediterranean
Sea) including available geographical knowledges of that
Fig. 1. Pic. of Alexandria lighthouse by Magdalena van de Passe
REVIEW
Geodesy and Cartography, 2012, 38(2): 81–85 83
period about the settled areas of the world. e map cov-
ers Europe and a part of Asia up to the Indian Ocean the
Bay of Bengal (Mer Orientale) and Sri Lanka (Tap r o b a n e )
(included), in the South it includes the Ethiopian Ocean
(Ocean Ethiopien), Northern and Central Africa with
pointed names of Libya, Ethiopia and Nubia, limiting it-
self to the Arabian Sea (Mer Erythree) (Fig. 3).
e stretch of the map according to the mentioned
values of marginal parallels and meridians is a rectangle
of 12 000×6000 km. e researchers of Eratosthenes map
claim that he had marked quite many locations based on
astronomical measurement.
It is possible to give a present geographical name to
every name of Eratosthenes map grid with the exception
of ules meridian. We may only guess it might be the
present Iceland. is island was described by a Greek trav-
eller and geographer Pytheas of Massalia (320–285 B.C.)
as the one to the North from the British Islands at a dis-
tance of 6-day travelling; aer one more additional day
you will see the frozen Cronian Sea. e sun sets here
only for 2 or 3 hours. Later exponents of ule Island
guess that Pytheas himself had never visited the island;
he only managed to collect the data about this Northern
island or coastline. According to F. Nansen it could have
been Iceland or Norway.
Fig. 2. Mappa mundi by Dicaearchus (from Rumsey Map Collection 2009)
Fig. 3. Mappa mundi by Eratosthenes
REVIEW
84 V. Lukoševičius, T. Duksa. Eratosthenes’ map of the oecumene
Even more dispute was received regarding an over-
land unlimited area in the North nearby marked as
Baltia. Pytheas in his description conrms that on his
way home he sailed through a wide channel and reached
an island, rich in amber, which was supposedly collect-
ed by local inhabitants for fuel. It is a question whether
Pytheas really visited or not the Baltic coastline, he may
have just heard of it; but this is the rst time name Baltia
was mentioned. On the basis of this fact, the linguist
Nesselmann (1811–1881) suggested calling the inhab-
itants of the Baltic coastline (Latvians, Lithuanians and
Prussians) by a common name as the Balts (Statkutė de
Rosales 2009).
4. Geographical net of Eratosthenes’ map
e content of the map is limited that period of time by
the farthest known meridians and parallels of the Earth
with their named values in stadia. Western meridian with
zero stadium was selected without identifying it with any
concrete local object; the meridian was drawn in the
ocean next to the coastline of West Europe and Africa.
e eastern outside meridian with 80 000 stadia is
made behind the Hindustan Peninsula and Ceylon Is-
land ignoring the mapping of farther Asian territory. It is
necessary to state that the Hindustan Peninsula is unre-
alistically pulled east, so its deformity captures attention
the most. e majority of inside meridians are identi-
ed with not very precisely concretized objects (Bouches
Table 1. Parallels of the Eratosthenes’ map
Names of parallels Present map names Values of parallels in
stadia and degrees
Present values of
parallels
Note
De ule Iceland 46 400–66°18’ 66°00’ North of Iceland
Du Borysthene Dnieper entry 34 900–49°52’ 46° 35’ Parallel was also called by the
name of Olbia (Gedgaudas 1994),
Ukraine at present
De Byzance Istanbul 32 200–46°00’ 41°00’ Byzantium – capital of the Eastern
Roman Empire next to the entran-
ce to Bosporus
DʼAmisus Samsun 29 900–42°42’ 41°17’ Settlement in the North of Turkey
next to the Black Sea
De Gades Cadiz Nondigital parallel 36°32’ Cadiz – town in the SW part of
Spain and gulf with the same
name
De Rhodes Rhode Island 25 000–35°43’ 36°00’ Greece
De Babylone Vanished city of
Babylon
23 200–33°08’ 33°10’ Historical city (Kindersley 2005),
today Iraq
DʼAlexandrie Alexandria 21 800–31°08’ 31°12’ Egypt
De Syene Aswan 16 800–24°00’ 24°05’ Aswan is also known as the name
of the dam, Egypt
De Meroe Meroe 11 800–16º52’ 16°56’ Place of pyramids in Upper Nubia
near the Nile, towards North from
Khartoum next to Kabushiya
settlement (Sudan)
de Nil – the Nile entry, p. Caspiennes – the Gates of the
Caspian Sea, Bouches de Indus – the Indus entry, Bouches
du Gange – the Ganges entry). As the deltas of the great
rivers in the map created more than two thousand years
ago could have been notably dierent, the precision of
marked meridians is not analyzed in the article. Regard-
ing the deformity of the map in the East meridian, lined
across C. Coliaque Cape has got inaccurate marking in
stadia. Nowadays this Cape of Hindustan Peninsula is
called Cape Komari (Comorin) (Kindersley 2005).
Northern outside parallel with 46 400 stadia mark-
ing crosses in the North ule Island, while the bottom
outside parallel in the South with 8000 stadia marking
crosses the Ethiopian Ocean (Ocean Ethiopien), the Nile
(Nil) source, the Arabian Sea (Mer Erythree) and nal-
ly crosses Ceylon (Taprobane) Island. A surprising fact
here is that the top parallel of ule with its marking
quite precisely repeats the northern geographic co-ordi-
nate of Iceland. However, the same cannot be said about
the southern co-ordinate connected with Ceylon Island
where the map deformity is noticeable.
A famous ancient Greece astronomer Hipparchus of
Nicaea (160–125 B.C.) while criticizing the map of Era-
tosthenes developed a few geometrical methods of globe
meridians and parallels projection onto a plane and
coined “geographic co-ordinates” notion to talk about
dierent the Earth surface points, and also showed the
method how to set them.
REVIEW
Geodesy and Cartography, 2012, 38(2): 81–85 85
5. Conclusions
1. e table comparing the Eratosthenes map paral-
lel values of Alexandria, Syene (Aswan), Babylon
and Meroe with parallel values of present settle-
ments proves the dierences to be minor and the
measurements, conducted by Eratosthenes at that
time, are suciently precise (see Table 1).
2. e map named Borysthene (the Dnieper) paral-
lel which in 372 A.D. in cartography was called
as Olbia (Gedgaudas 1994) aer the name of in-
ternational port above the Dnieper entry of that
period. It proves the importance of the port of
Amber Road.
3. Inscription BALTIA in mapping for the rst time
in the history of cartography was used in the map
of Eratosthenes.
4. While compiling the map, Eratosthenes did not
have enough geographical information regarding
the oecumene’s eastern part, so this part of map
includes the biggest error.
References
Chomskis, V. 1979. Kartograja. Vilnius: Mokslas. 336 p.
Gedgaudas, Č. 1994. Tikrosios Lietuvos beieškant. Kaunas: Auš-
ra. 359 p.
Harwood, J. 2008. Pasaulis žemėlapiuose. Mūsų knyga. 192 p.
Kindersley, D. 2005. Conicise. Atlas of the world. DK, London,
New York, Munich, Melbourne, Delhi. 350 p.
Kudaba, Č. 1980. Geogranės kelionės ir atradimai. Vilnius:
Mokslas. 294 p.
Rumsey, D. 2009. Internetinė kartogranė svetainė. Available
from Internet: www.davidrumsey.com/about/articles/about
Samas, A. 1997. Žemėlapiai ir jų kūrėjai. Vilnius: Mokslo ir en-
ciklopedijų leidybos institutas. 197 p.
Statkutė de Rosales, J. 2009. Senasis aisčių giminės metraštis.
Česlovo Kudabos labdaros fondas, Kaunas. 275 p.
Teeple, J. B. 2002. Timelines word of history. London. 666 p.
Viktoras LUKOŠEVIČIUS. Doctor, Prof. Dept of Civil Engi-
neering Technology, Šiauliai University, Ph +370 41 595843,
Fax +370 41 595832.
A graduate of Kaunas Polytechnic Institute (now Kaunas
University of Technology), geodetic engineer, 1962. Doctorʼs
degree at Institute of Surveying, Aerial Photography and Car-
tography, Moscow, 1966. Publications: 2 books, over 70 rese-
arch articles; participant of conferences in USA, Brasil, Sweden,
Norway, Russia. Fellowship Winner, NATO and Italy National
Science Competition, 1996. Member of Association for the
Advancement of Baltic Studies.
Research interests: history of geodesy and cartography.
Tomas DUKSA. Geographer, Lithuanian Cartographic Society,
Ph +370 52398297, +370 52470760.
A graduate from Vilnius University, cartographer, 1972.
Publications: over 10 scientic articles, a participant of confe-
rences held in Poland, Czech Republic, Latvia, Estonia, Belorus
and Russia.
Research interests: history of cartography.
REVIEW
ResearchGate has not been able to resolve any citations for this publication.
Kartografija. Vilnius: Mokslas
  • V Chomskis
Chomskis, V. 1979. Kartografija. Vilnius: Mokslas. 336 p.
Tikrosios Lietuvos beieškant. Kaunas: Auš-ra
  • Č Gedgaudas
Gedgaudas, Č. 1994. Tikrosios Lietuvos beieškant. Kaunas: Auš-ra. 359 p.
Geografinės kelionės ir atradimai. Vilnius: Mokslas
  • Č Kudaba
Kudaba, Č. 1980. Geografinės kelionės ir atradimai. Vilnius: Mokslas. 294 p.
Internetinė kartografinė svetainė
  • D Rumsey
Rumsey, D. 2009. Internetinė kartografinė svetainė. Available from Internet: www.davidrumsey.com/about/articles/about
Žemėlapiai ir jų kūrėjai. Vilnius: Mokslo ir enciklopedijų leidybos institutas
  • A Samas
Samas, A. 1997. Žemėlapiai ir jų kūrėjai. Vilnius: Mokslo ir enciklopedijų leidybos institutas. 197 p.
Senasis aisčių giminės metraštis, 275Kaunas: Česlovo Kudabos labdaros fondas
  • J Statkutė De Rosales
Timelines word of history
  • J B Teeple
Teeple, J. B. 2002. Timelines word of history. London. 666 p.
Pasaulis žemėlapiuose. Mūsų knyga
  • J Harwood
Harwood, J. 2008. Pasaulis žemėlapiuose. Mūsų knyga. 192 p.
Available from Internet: www.davidrumsey.com/about/articles/about
  • D Rumsey
  • D Kindersley
Kindersley, D. 2005. Conicise. Atlas of the world. DK, London, New York, Munich, Melbourne, Delhi. 350 p.