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World View what is the world like


World View what is the world like... Ancient and Medieval Maps ... This style of map of the world was the routine way to show the world. ... – PowerPoint PPT presentation

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Title: World View what is the world like

World View what is the world like Ancient and
Medieval Maps Renaissance and the Age of
Exploration Early Modern Maps Modern Views of
the World
After St Augustine made the study of religion the
major focus of human thought, the early church
adopted the literal interpretation of the Bible
as the source for geographical information.
This was summed up by a monk, Cosmas
Indicopleus , who around 547 CE wrote a treatise
called Topographia Christiana which suggests that
the world is a flat surface with a sky above, and
above the sky, heaven. Jerusalem was the center
of the world, and the Garden of Eden off to the
east. The sun revolved around a mountain to the
north and was much smaller than the Earth. This
rejected the knowledge of the Greeks who had
agreed that the Earth was round (Aristotle had
written that the shadow of the Earth on the Moon
was rounded, so the Earth must be a sphere) and
who had made quite accurate measurements of the
circumference of the Earth as equivalent to
25,000 miles. But Aristotle and the other Greeks
were seriously wrong about some other ideas of
geography. They divided the Earth into zones, and
said that the Equatorial zone was too hot for
human life, and the far north and south too cold.
So only the northern regions from Egypt up to the
northern forests were suitable for life. They
also said that Asia must extend far to the east
and that there would be no land between the
eastern end of Asia and the western end of
Europe. Also, they clearly said that the Earth
was immobile in space, and was the center of the
universe, with the planets and stars revolving
around it.
c.html A neat animation that shows how the
Ptolemaic astronomers explained the motions of
the sun and planets this would be a geocentric
world system.
htm A link to a translation of Cosmas
Indicopleus 547 CE account of the shape of the
world The Deity, having thus in the order of
nature, as the scripture declares, suspended the
earth upon nothing, when it had reached the
bottom of space laid its foundations upon its own
stability so that it should not be moved for
Not really a medieval picture, but from a book
written in 1888 about what medieval people
A medieval European map of the world. The world
is divided into three sections. North is at the
left. The three sections are named for the three
sons of Noah as recorded in the Bible (Genesis
918) who were Shem (father of the Semitic
people) , Ham (father of the Hamitic or African
people) and Japheth (father of the Europeans.)
The Orient is at the top and the Occident
(West) is at the bottom. The meridien or southern
part of the world is at the right. The world
is divided by the Mediterranean and the large sea
(consisting of what we would call the Danube
River, the Caspian Sea, the Euxine or Black sea,
the Nile and Red Sea extending to the Ocean Sea
which surrounds the entire world. This style of
map of the world was the routine way to show the
world. Maps of this kind are called T and O
maps. A Crusader starting off from, say, the
Tower of London, on his way to Jerusalem would
have probably had no more map than this.
Even after the early navigators had learned more
about the world, the traditional maps were still
produced. The T and O map on the right was
printed in 1493. It divides the world by the
Mediterannean and the Danube separating Europe
and Asia, while the Nile separates Asia and
Africa. The map at left, of about 1100 CE, now
in the Library of the Vatican, shows Jerusalem at
the center of the Earth, with the Garden of Adam
and Eve marked where the Bible places it
eastward in Eden (Genesis 2,3).
The Hereford Mappa Mundi -------------------------
----- A T and 0 map of about 1300 CE on display
in Hereford Cathedral in England. Drawn on a
single sheet of vellum, It is well over 1 meter
square. Jerusalem is at the centre of the
circle, East is on top, showing the Garden of
Eden in a circle at the edge of the world. Great
Britain and Ireland are at the north-western
border (bottom left). Medieval scholars knew
that the Earth was spherical, but they believed
that the extreme northern and southern parts of
the world were uninhabitable, so those did not
need to be shown. The large river on the far
right is the Nile, Which flows into the
Mediterannean. The Don river flows into the
Mediterannean from the left.
The Ebstorf map a T and O map of 1234 CE made
by Gervase of Tilbury, an English scholar and
diplomat who served various courts in Europe and
was able to visit many scholars and centers of
scholarship. He wrote a compendium of stories
which he collected as he travelled, many of which
are out and out folklore. This map was destroyed
during WW II.
While many were still ignorant of the shape of
the world, at the same time, the serious
navigators were making maps that were closer and
closer to the real shape of the world. The
Spanish and Portuguese especially were exploring
the trade routes to the East. This map shows a
rather good depiction of Asia Minor (Turkey) with
the Black Sea shown quite accurately , and the
Caspian Sea correctly shown as landlocked. Also,
Egypt with the Nile, the Red Sea, a somewhat
distorted Arabia, India, and then a confused SE
Asia with the mythical island of Tapobana.
This map was drawn about 1470 1490 based on
the descriptions of the world given by Claudius
Ptolemaeus (Roman lived about 90 CE to 170 CE),
called Ptolemy. Columbus would have used this
map, or others very similar to it to plan his
According to historian Matt Rosenberg, not much
is known about the life of the Roman scholar
Claudius Ptolemaeus who is more commonly known as
Ptolemy. However, he was estimated to have lived
from approximately 90 to 170 CE and he worked in
the library at Alexandria from 127 to 150. He is
known for his three scholarly works the Almagest
- which focused on astronomy and geometry, the
Tetrabiblos - which focused on astrology, and,
most importantly, Geography - which advanced
geographic knowledge. Geography consisted of
eight volumes. The first discussed the problems
of representing a spherical earth on a flat sheet
of paper (remember, ancient Greek and Roman
scholars knew the earth was round) and provided
information about map projections. The second
through seventh volumes of the work were a
gazetteer of sorts, as a collection of eight
thousand places around the world. This gazetteer
was remarkable for Ptolemy invented latitude and
longitude - he was the first to place a grid
system on a map and use the same grid system for
the entire planet. His collection of place names
and their coordinates reveals the geographic
knowledge of the Roman empire in the second
century. The final volume of Geography was
Ptolemy's atlas - featuring maps that utilized
his grid system and maps that placed north at the
top of the map, a cartographic convention that
Ptolemy created. Unfortunately, his gazetteer and
maps contained a great number of errors due to
the simple fact that Ptolemy was forced to rely
upon the best estimates of merchant travelers
(who were incapable of accurately measuring
longitude at the time). Like much knowledge
of the ancient era, the awesome work of Ptolemy
was lost for over a thousand years after it was
first published. Finally, in the early fifteenth
century his work was rediscovered and translated
into Latin, the language of the educated
populace. Geography gained rapid popularity and
there were more than forty editions printed from
the fifteenth through sixteenth centuries. For
hundreds of years, unscrupulous cartographers of
the middle ages printed a variety of atlases with
the name Ptolemy on them, to provide credentials
for their books. (Matt Rosenberg)
Eratosthenes Measures the World in Ancient Egypt
-- 200 BC Eratosthenes was born in the Greek city
of Cyrene in Libya in 276 BC, educated in Athens,
and died in the Greek City of Alexandria in Egypt
in 194 BC. Remember that Alexander the Great, a
Macedonian Greek, conquered Egypt and around
330.B.C he founded a new city there which he
modestly named after himself, Alexandria. One of
his generals took over Egypt when Alexander died.
Then for 300 years the general's descendants were
rulers of Egypt and were called "Hellenic" (Greek
for "Greeks"). There was a long series of Greek
rulers who were mainly called Ptolemy if they
were male or Cleopatra (Greek for "Father's
Glory") if they were female. This line continued
right down to the famous Cleopatra who fooled
around with Julius Caesar - she was actually
Cleopatra Theo Philopater (the VII) and her
father was Ptolemy XII Auletes. But that was a
lot later, she became queen in 51 B.C. About 245
B.C. Eratosthenes was brought from Athens to
Alexandria by the Hellenic (Greek) Pharoah
Ptolemy II Euergetes to be the tutor for the
Pharoah's son. A few years later he became the
3rd Head Librarian of the Great Library, the
Mouseian (Library of the Muses), which had been
built by the previous Greek Pharoahs Ptolemy I
and Ptolemy II Philadelphus to house copies of
the works of the Greek writer Aristotle and other
scrolls. He probably got the Alexandria job
because the 2nd head librarian, Callimachus, had
been one of his teachers in Athens. Nothing like
a good "networking" connection! Historical
accounts from the ancient historian Strabo and
several later authors tell us that Eratosthenes
made a very good estimate of the actual size of
the earth by the following method one day as he
was researching in the library he found a book
that said, on the longest day of the year the
reflection of the sun could be seen at the bottom
of a deep well in the city of Syene, in southern
Egypt. This is an important observation. It means
that in Syene the sun had to be directly overhead
on that day of the year. But, he knew that on
Midsummer Day the sun at Alexandria did cast a
small shadow. That is, the sun was nearly, but
not quite, directly overhead -- about a 7 degree
angle. If the earth was flat, this would not be
possible. The earth had to be curved and the
distance from Alexandria to Syene had to
represent 7/360ths of the total. OK, if it is
about 500 miles between the two cities, then
500/7 x 360 about 25,700 miles around the earth
-- that is, by simple geometry he could calculate
the angles and the whole distance around the
earth. He didn't have an accurate clock,
astronomical instruments or measuring devices,
but still, since the actual distance is now
measured as a little less than 25, 000 miles he
did pretty well for 200 B.C.!
Columbus? But what about Columbus? Didn't he
"prove the world was round? Ha! As you know,
the idea that in 1492 educated people thought the
earth was flat is silly. The story of Columbus
arguing with people about whether the Earth was
round or flat was probably made up around the
year 1800 by the American author Washington
Irving for a book he was writing about Columbus.
The real argument with Columbus was not whether
the earth was round, but whether it was possible
to sail far enough to get around it -- to sail to
China. The Spaniards wanted to get to China and
the Orient in order to trade for spices, silk and
other valuable goods as Europeans had been doing
for centuries. But, in the late 1400s they could
not sail through the Mediteranean. At that time
the Turks and other Muslim rulers had blocked the
trade routes. In 1454 the Turks captured the
major Christian city of Constantinople (Istanbul)
and cut off trade almost completely. Europeans
were desperate for the Asian spices, and there
was a fortune to be made by anyone who could get
them. Portuguese sailors were trying to get to
China and India by working their way eastward
around Africa, but Columbus wanted to sail
directly westward to reach China. What was the
argument? Columbus said he could sail west to
China. The Spanish court geographers said it was
impossible. The disagreement was not about
whether the Earth was flat -- only ignorant
peasants believed that! The argument was about
how far it was to China. Every trader knew that
it was approximately 9,000 to 10,000 miles
eastward from Europe to China by the ancient
trade routes -- those roads had been travelled
for centuries. And, the geographers knew that the
Earth was about 25,000 miles around, so that
meant that sailing westward to China could be a
15,000 mile trip or more. No one, including
Columbus, believed that their ships could sail
that far without stopping for repairs and
supplies. And, that's why the King of Spain was
so reluctant to give Columbus any ships or
sailors. Once Columbus set sail, no one expected
to see him alive again! In the end the King just
gave Columbus some old ships that weren't worth
much, and prisoners from the local jail for
sailors -- no one would miss them. What was
Columbus' big idea? Columbus claimed that the
distance around the world was only about 18,000
miles at most -- he was depending on the estimate
made by the ancient scholar Ptolemy whose
calculations translate to about 18,600 miles in
modern terms. That meant that in Columbus'
calculations, the distance to China by sea was
only 7,000 to 8,000 miles rather than 15,000.
That was still a very long sail, further than any
European ship had ever sailed out of sight of
land. But, it was a lot shorter than going all
the way around Africa to China. He thought that
with luck he might make it, and he was courageous
enough to take a chance. Unfortunately for
Columbus, the King's court geographers were
almost exactly right and he was dead wrong. It is
over 13,000 miles westward from Spain to China.
His leaky ships would never have made it all the
way! But fortunately for Columbus, when he had
sailed less than 4000 miles and his ships were
starting to have problems, America got in the way
and saved him from being drowned. He was foolish
and wrong, but he was also brave and determined.
Without his persistence, the Americas might not
have been discovered for hundreds of years
more.... the United States would probably never
have existed. World history would have been
totally different! So, was he a hero or not? p.s.
Like many famous historical figures, our image of
Columbus is quite distorted. The accounts of his
appearance written by people who actually knew
him all agree that he had red hair and a fair,
ruddy complexion. He was Italian, but from the
North of Italy, not Sicily. (see the classic
biography, Admiral of the Ocean Sea by S.E.
This map was draw just about 50 years after the
Ptolemy map shown in the previous slides was
This map of the Americas was drawn by the
brilliant Dutch mapmaker Ortelius who was active
mainly between about 1587 to 1612.
Longitude The failure to be able to accurately
calculate longitude was a major problem for
navigators up to the end of the 1700s. Without
calculations of longitude the sailors mostly had
to creep along the shoreline, never venturing far
out to sea, for fear of losing their bearings.
Those who wanted to trade over long distances
were seriously constrained by the lack of proper
methods for finding their way on the ocean.
Among the earliest scholars to try to address
the issue of navigation was an Englishman who
became a kind of math tutor to Phillipa, the
granddaughter of King Edward III of England.
Later when she was married to the King of
Portugal she remembered her lessons and taught
them to her son Henry. Henry caught the
navigation bug from his mother and started a
school for navigation in Portugal. Though he
never went on long voyages himself, his support
for the courageous Portuguese explorers earned
him the title of Prince Henry the Navigator.
His mothers old tutor Geoffrey Chaucer! The
Portuguese explorers kept detailed records of
their voyages. How long they sailed, how strong
the wind was, everything that they could easily
observe. These records, called rutters were
considered trade secrets and pilots of the ships
would go to great lengths to protect them from
falling into the hands of rivals and enemies.
Still, they could not keep exactly correct
records as long as they could not calculate the
longitude. We will consider this problem further
later on.
An English map printed in 1800 after the
introduction of Harrisons clocks.
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