Transcript Exploration

Europe Reaches Out
The Age of Exploration
Entire populations and cultures
have been transplanted in recent
centuries
59 million inhabitants of Great Britain
• 270 million English-speakers in U.S.
• 30 million in S. Africa
• 28 million in Canada
• 18 million in Australia.
39 million inhabitants in Spain
• 250 million Spanish speakers in Latin
America
• Largest Spanish city is Mexico City (half the
population of all of Spain)
10 million inhabitants in Portugal
• 160 million Portuguese speakers in Brazil
• Largest Portuguese city is Sao Paulo (more
inhabitants than Portugal)
• Largest French city is still Paris
• But the second largest is
Montreal.
 16 million inhabitants in Holland, 10 million
Afrikaans speakers in S. Africa.
 There are 5 million Jews in Israel, 5 million
in the U.S.
 The second largest Polish city is Chicago.
 30 million blacks in the U.S. (only 6
countries in Africa have greater population)
The Impulse Toward Exploration
• Tantalizingly brief gap between several
medieval events and the European Age of
Exploration
• China closed itself to outsiders in 1368
• China's great voyages to Asia and Africa ended
in 1431
• Last ship to Norse colony in Greenland sailed in
1406
• Columbus sailed in 1492.
Factors in Exploration
 Accidental discovery.
 Desire to bypass Moslem world.
 Disruptions of overland routes (somewhat
overrated).
 Intra-European rivalry.
 Curiosity.
Major Events in Exploration
 African coast-route to India.
 Trans Atlantic voyages.
 Northwest and Northeast Passage.
 Pacific voyages.
 Circumnavigations
Circumnavigating the Globe
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Ferdinand Magellan (Spain) 1519-22
Sir Francis Drake (England) 1577-80
Sir Thomas Cavendish (England) 1586-88
Simon de Cordes (Holland) 1598-1600
Oliver Van Noort (Holland) 1598-1601
George Spilberg (Holland) 1614-17
James LeMaire and William Cornelius
Schouten (Holland) 1615-17
Some Observations
• Most of these voyages were for military
purposes (harassing the Spanish) rather than
discovery
• This pattern is very similar to the early days
of space exploration
• Not until the mid-1700’s were there
circumnavigations largely aimed at
exploration
• Drake and his fellow pirates would now be
called state-sponsored terrorists
A Geographical Oddity
• The easiest way to sail around the world is
from west to east, with the wind
• Almost all early voyages were from east to
west around South America
• Objective: secrecy in entering the Pacific
• Spanish tried and failed to establish
settlements at the Straits of Magellan
(weather poor, can’t raise crops, etc.)
A Geographical Oddity
The First Two (Three) -Time
Circumnavigator
• William Dampier (between 1679 and 1711)
seems to have been the first to circumnavigate
more than once (three times)
• Odds of surviving a circumnavigation were
very poor in early voyages
• The prevention of scurvy was not discovered
until around 1800
The First Two -Time Circumnavigating
Ship
• The Dolphin (1764-66 and 1766-68) was the
first ship to circumnavigate the globe twice
• It took almost 250 years after Magellan for
shipbuilding technology to be able to build
a ship capable of surviving two voyages
The First Commercial Round-theWorld Traveler
• By the 1600’s a globe-girdling network of
European trade routes was in place
• It was rarely necessary to circle the globe
• There were only about 25 circumnavigations
to 1800
• Giovanni Carreri (1693-98) sailed to Mexico,
crossed overland, then booked passage
across the Pacific and back to Europe
Why Did They Do It?
• Why did people risk their lives in tiny boats
to trade halfway around the world?
• Nowadays: bulk cargo. Ship more valuable
than cargo, but cost recovered by many
voyages (Exxon Valdez: 10 million gallons =
$10 million)
• 1600’s: cargo far more valuable than ship
• “My ship came in” - one good voyage could
set you up for life.
Strange ideas were not so strange
• Does it seem bizarre that Cartier could sail
up the St. Lawrence hoping to reach China?
 There was no clear idea how rivers were
fed or what made them flow.
• The coastline of Europe is one of the most
complex in the world.
• The one thing Europeans were not
prepared for was long regular coastlines
without geographical oddities!
Innovations that aided exploration
 Stern-post rudder
 Lateen and square sails in combination
 Compass
 Discovery of Trade Winds
Innovations derived from exploration
 New foodstuffs: coffee, tea, potatoes,
tomatoes, chocolate, squash, maize.
• Improvements in shipbuilding, charting,
navigation.
• General stimulus to discovery.
The Compass Crisis
• Compasses often pointed quite far from true
north
• Queen Elizabeth offered a prize to anyone
who could solve the problem
• The court physician, William Gilbert, in 1600
published De Magnete
De Magnete, 1600
• Considered the first great work on
magnetism
• Gilbert deduced the overall form of
magnetic fields and concluded that the
Earth had two magnetic poles
• Earth's magnetic field varies in space and
time. It changes measurably in a human
lifetime
Why Compasses Don’t Point True
North
• North Magnetic Pole is
not at the geographic
pole
• Declination in Wisconsin
is nearly zero
• Declination in Maine is 20
degrees West
• Declination in Seattle is
20 degrees East
Latitude and
Longitude
Latitude (N-S) is easy
to determine by
observing the stars
Latitude and Longitude
Longitude (E-W) cannot
be determined by simple
observation
– In a night, every
observer at a given
latitude sees the same
stars
– What differs is when
they see the stars
– The key to longitude
determination is time
Longitude = Accurate Time
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Circumference of Earth =25,000 miles, so:
One hour = 1040 miles at the equator
One minute = 17 miles at the equator
One second = 0.3 miles at the equator
Clock has to be accurate to seconds over a
span of months, on a rolling ship, in all
weather and climate.
Astronomical Methods
• Eclipses of Moon: Everyone who sees the Moon sees
the same thing
• Too rare for most purposes
• Eclipses of Jupiter’s moons: frequent but hard to
observe
• Method never panned out
An Unexpected Spinoff
• The Dutch astronomer Roemer found eclipses
ran early or late
• Discrepancy = time for light to cross Earth’s
orbit
• First evidence that light had a measurable
speed
The Final Solution - A Good Clock
• One of the great technological stimuli of all
time
• John Harrison, 1761
• Need high-quality steel for springs
• Need accurate tools to make gears and
other parts
• With good steel and accurate machine
tools, what else can you make?
Anything at All
The Other Immigrants
• Rats and ships are synonymous
• Dogs (for companionship) and pigs (for food)
were common passengers on early voyages
• Rats, dogs and pigs wreaked havoc on many
island ecosystems
• Horses were reintroduced to the Americas by the
Spanish and were utilized by Indians far outside
the zone of immediate contact
• The most significant travelers were microscopic
Pre-Contact America
• Pre-contact population of Americas once
estimated at perhaps 5-10 million
• Estimates based on
– Observed population at time of contact
– Stereotype that Indians could not sustain a
complex society
• Early estimates now known to be at least 10 times
too small
• May have been more people in the Americas than
Western Europe
Conquest of the Americas
• Europeans greatly outnumbered
• Weapons advantage potentially offset by
numbers
• European mortality high from disease
• Spanish had been expelling Arabs for 700
years
• No reason to expect native societies to
collapse upon conquest
• Not the slam dunk we sometimes think
The Micro-Immigrants
• Indians isolated from Old World disease
pool
• Introduced diseases: smallpox, chicken pox,
measles, cholera, malaria
• Effects extended far beyond contact areas
• Overall mortality may have been 80%+
• Why didn’t diseases travel other way as
well? (Syphilis?)
The Course of One Epidemic
Two Important Points about Disease
in the New World
• First Europeans did not know they
were carrying contagious diseases
• Europeans did not know that Indians
lacked immunity to European diseases
• Would things have been different if
they had known? Maybe not, but you
can’t judge people for what they might
have done