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  #1  
Old 10-23-2007, 10:57 AM
Don't fight the hypothetical Don't fight the hypothetical is offline
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Did Europeans believe that the world was flat in 1492?

I've always heard that was true. It's always surprised me that the Greeks knew the world was round yet but in the 15th century that information was lost. Didn't Columbus sail against contemporary thinking in that regard? But in the current zombie thread that's floating around in GQ, there's this:
Quote:
Colibri: "In the popular mind, Columbus was supposedly arguing that the world was round, while the wise men insisted it was flat. Actually the experts told him he couldn't reach Asia by sailing west because it was too far away , not because the idea wasn't right in theory."
So the experts knew but did the average Joe in 1492 think the world was flat or round?
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  #2  
Old 10-23-2007, 11:05 AM
CalMeacham CalMeacham is offline
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Experts certainly knew and, as Colibri pointed out, had a better idea of its proper size than Columbus.

Did the average guy know? Probably not. It wasn't something he'd be likely to encounter. As George Bernard Shaw pointed out, there's a compelling argument for its flatrness: "Look at it".

I'll bet general knowledge of the true shape of the earth (and of maps, the sizes and locations of countries, etc.) didn't start becoming "common knowledge" until general education became a regular thing, and then, it was only within certain groups. I'm always impressed by the general knowledge of the early settlers of Pluymouth and other parts of New England (probably elsewhere, toom, but I;'m not as well-read on Southern colonies), and I figure their forebears must have been as well informed. I'll bet that a lot of this was the result of small Protestant groups in the British Isles forming their own schools affiliated with the churches. So by the mid-16th century I'll bet this knowledge was beginning spread within groups there. Eventually it hit the general populace, but I don't know when that would be -- by the late 18th early 19th century, certainly.

How all this went elsewhere in the world I can't say. Did Jewish education extend beyond Torak and Talmud to general science and other subjects? That was widespread and not just for the well-off. Other groups have traditions of teaching, but I know little about them.
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Old 10-23-2007, 11:14 AM
brickbacon brickbacon is offline
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Quote:
Originally Posted by Don't fight the hypothetical
So the experts knew but did the average Joe in 1492 think the world was flat or round?
People knew the world was round . In fact, many say Washington Irving is partly responsible for perpetuating a myth. On last cite for all the doubters:

Quote:
This just canít be true, say my critics. After all, didnít the Church teach that the world was flat?

Actually, no. Essentially no one during the Middle Ages believed the world was flat. Of the many myths about the Middle Ages this one is perhaps the most widespread, and yet at the same time the most roundly and authoritatively debunked.

In fact, the evidence is so overwhelming that refuting this myth is like refuting the idea that the moon is made of cheese.
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Old 10-23-2007, 11:19 AM
Derleth Derleth is online now
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Quote:
Originally Posted by CalMeacham
As George Bernard Shaw pointed out, there's a compelling argument for its flatrness: "Look at it".
Which argument loses a lot of power if you live near the ocean and see ships disappearing from the bottom up and appearing from the top down. Or if you walk far enough from town all you can see is the church tower, or the tops of the highest hills.
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Old 10-23-2007, 11:44 AM
Freddy the Pig Freddy the Pig is offline
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Quote:
Originally Posted by Don't fight the hypothetical
I've always heard that was true.
Then you should read more books. Or even, one book about Columbus or the European Age of Exploration.

I don't mean that in a snarky way. If you believe that Columbus had to fight people who thought the world was flat, you have major gaps in your knowledge, and you'll enjoy learning more.
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Originally Posted by Don't fight the hypothetical
It's always surprised me that the Greeks knew the world was round yet but in the 15th century that information was lost.
Nothing was lost. When we say that "the Greeks knew the world was round", we mean that the writing of a few Greek thinkers has survived, in which those thinkers proved in a satisfactory manner that the world was round. We don't mean that every uneducated person in ancient Greece knew this, any more than every uneducated person knew it in medieval Europe.
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Originally Posted by Don't fight the hypothetical
Didn't Columbus sail against contemporary thinking in that regard?
The idea of long-distance sailing wasn't original with Columbus. By 1492, the Portuguese had been exploring Africa for 77 years, and had sailed around its southern point and nearly to India. They had ample opportunity to observe the Southern constellations and how the sky changed in appearance due to the sphericity of the Earth. None of this was new in 1492.
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Originally Posted by Don't fight the hypothetical
So the experts knew but did the average Joe in 1492 think the world was flat or round?
You've misquoted Colibri. He says that "experts" offered a better opinion than Columbus as to the size of the Earth, not that only experts knew the world was round. By 1492, every educated European knew the world was round. It wasn't a point of issue. We don't know about "average Joes", only because they were illiterate and didn't leave any records about what they knew.
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Old 10-23-2007, 12:47 PM
astorian astorian is offline
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And, for the record, while the Church got a lot of things wrong about the solar system, the shape of the Earth was never in question. Long before Columbus, St. Thomas Aquinas wrote

". . .it should be noted that the different ways of knowing (ratio cognoscibilis) give us different sciences. The astronomer and the natural philosopher both conclude that the world is round, but the astronomer does this through a mathematical middle that is abstracted from matter, whereas the natural philosopher considers a middle lodged in matter. Thus there is nothing to prevent another science from treating in the light of divine revelation what the philosophical disciplines treat as knowable in the light of human reasonĒ (Summa theologiae, Ia, q. 1, a., ad 2).


So, even the Church acknowledged that the Earth was round long before 1492.
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Old 10-23-2007, 12:58 PM
kellner kellner is offline
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The Nuremberg Chronicle was completed in 1493, just before any results of the Columbus voyages could be incorporated. It contains an overview of the history of the world as it was understood at the time. It isn't an academic geography text but closer to a popular science book. Nevertheless by the standards of the time it was a major book project aimed at an educated audience.

The text does not give the exact shape of the earth but it mentions the possibility that it is a sphere.
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The world is called a circumference because it is simply [~a round disc] or a sphere.
(a more literal version of the first shape would be something like "rotundly disced" - whatever exact shape that is supposed to be.)
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Old 10-23-2007, 01:03 PM
Napier Napier is offline
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I once read that Columbus's reputation and the story of his boldness was fluffed up by Washington Irving at the request of a consortium of Italian-American businessmen, who paid him for it, and that he invented the idea Columbus demonstrated the world was flat.

This does sound pretty whacky, so I'd appreciate hearing from anybody who has a better understanding of this and maybe could correct it.

In any case, there's an old painting of Columbus holding an octant (which is an earlier version of the sextant). Now, why would people have been building octants for navigation if the world was flat?
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Old 10-23-2007, 01:53 PM
tomndebb tomndebb is offline
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Quote:
Originally Posted by Napier
I once read that Columbus's reputation and the story of his boldness was fluffed up by Washington Irving at the request of a consortium of Italian-American businessmen, who paid him for it, and that he invented the idea Columbus demonstrated the world was flat.
i cannot state that this is impossible.

I can state that the number of "Italian businessmen" in the U.S. at the time the Irving was making up his tall tales was miniscule and the whole notion of propping up a "fellow countryman" would probably have had to wait another sixty or seventy years until the rush of Italian immigrants swelled to the point where xenophobes would have begun disparaging them, creating an audience for a popular hero with whom they could identify. (And this does not even address the point that there was no Italy for about 30 years after Irving wrote his Columbus biography: there was clearly a geographical Italy in the form of the boot-shaped peninsula, but in the 1830s, what would become the Nation of Italy was a scattered bunch of small kingdoms, often dominated by Austria or threatened by France.)


ETA: as Brickbacon's cites note, the primary interst in Irving when shaping his story appears to be simple anti-Catholic rhetoric.

Last edited by tomndebb; 10-23-2007 at 01:55 PM..
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Old 10-23-2007, 02:09 PM
Don't fight the hypothetical Don't fight the hypothetical is offline
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Quote:
Originally Posted by Freddy the Pig
You've misquoted Colibri. He says that "experts" offered a better opinion than Columbus as to the size of the Earth, not that only experts knew the world was round. By 1492, every educated European knew the world was round. It wasn't a point of issue. We don't know about "average Joes", only because they were illiterate and didn't leave any records about what they knew.
From Why did Columbus Think that He Discovered a Route to the Far East? (post #17), here is the entire quote:

"Columbus was truly the luckiest crackpot in history. His theory about the location of Asia relative to Europe was completely wrong, and the real geographical experts knew it. In the popular mind, Columbus was supposedly arguing that the world was round, while the wise men insisted it was flat. Actually the experts told him he couldn't reach Asia by sailing west because it was too far away , not because the idea wasn't right in theory." (bolding mine)

If I misquoted Colibri I apologize but I don't believe I did.
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Old 10-23-2007, 02:25 PM
sqweels sqweels is offline
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This is interesting because I recently got into an MB debate with a fundie who insisted that Colombus got the idea that the world was round from the Bible (which at one point refers to the "circle" of the world), and that the scientists of the day were hung up on "flat-earth theory". Therefore the Bible is reliable and science is not.

When I posted the following quote from Wikipedia...

Quote:
Following Washington Irving's myth-filled 1828 biography of Columbus, Americans commonly believed Columbus had difficulty obtaining support for his plan because Europeans thought the Earth was flat.[8] In fact, few at the time of Columbusís voyage, and virtually no sailors or navigators, believed this.[9] Most agreed that the Earth was a sphere. This had been the general opinion of ancient Greek science... Knowledge of the Earth's spherical nature was not limited to scientists: for instance, Dante's Divine Comedy is based on a spherical Earth. Columbus put forth arguments based on the circumference of the sphere. Most scholars accepted Ptolemy's claim the terrestrial landmass (for Europeans of the time, comprising Eurasia and Africa) occupied 180 degrees of the terrestrial sphere, leaving 180 degrees of water/
...she quite predictably argued that it was all a liberal media hoax.
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Old 10-23-2007, 03:20 PM
Arnold Winkelried Arnold Winkelried is offline
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This is probably a stupid question, but I'll venture to ask anyway.

When experts were telling Columbus he couldn't take enough supplies for his trip, did they mean food or drink?
If it was food, why couldn't the sailors catch enough fish during the trip to supplement their supplies enough to complete the trip? Drag a net behind the boat and haul it up twice a day.
If it was drink, I imagine it would be hard to distill enough salt water during your trip for everybody on board.

Last edited by Arnold Winkelried; 10-23-2007 at 03:21 PM..
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Old 10-23-2007, 03:23 PM
dangermom dangermom is offline
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Sqweels, does she think that C. S. Lewis is a horrible liberal? Because he wrote a book that describes it very nicely. It's called The discarded image and is one of my favorite books. Also people are tired of me shilling for it on every thread about the earth.
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Old 10-23-2007, 03:32 PM
scotandrsn scotandrsn is offline
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I would venture to say that since Dante's Divine Comedy of the 1300s took place in a round-earth Universe and was one of the most widely-known literary works for a couple centuries afterward, I would say that every single literate person, and a fair number of illiterates, were probably aware of that the Earth was round.
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Old 10-23-2007, 03:55 PM
filmyak filmyak is offline
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No cites, sorry, but a book I read in college (where I first learned that the "flat earth" story was a bunch of bull... sigh, American education sucks) went into some detail about this. From what I remember, Columbus compiled various theories as to how large the circumference of the earth actually was.

Knowing he'd never get funding to sail west to the Indies if the world was too large, he threw out the larger (and, it turns out, more accurate estimates) and used only the smaller (incorrect) estimates to help make his case that the journey could actually be accomplished.
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Old 10-23-2007, 04:09 PM
Colibri Colibri is online now
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Quote:
Originally Posted by Arnold Winkelried
This is probably a stupid question, but I'll venture to ask anyway.

When experts were telling Columbus he couldn't take enough supplies for his trip, did they mean food or drink?
If it was food, why couldn't the sailors catch enough fish during the trip to supplement their supplies enough to complete the trip? Drag a net behind the boat and haul it up twice a day.
If it was drink, I imagine it would be hard to distill enough salt water during your trip for everybody on board.
The productivity of the ocean way out away from land is pretty low. While you can haul up fish in coastal waters where nutrients are high, in mid ocean nutrients in the water are very low, and thus so is planktonic productivity and so also fish. You couldn't rely on catching enough fish to feed the whole crew every day. Besides, the crew would get sick of it and mutiny.

Food preservation methods were poor. Ships would stow hardtack, flour, salted meat and fish, dried peas, and so on. But in the permanently damp sea atmosphere this even this stuff would go bad eventually. Barrels of salt meat would spring a leak and be ruined.

Likewise ships would have casks of water, but these might also leak. You could collect some water by catching rain in sails, but remember the sails would also be full of salt from spray and this would not be too palatable. And it would be a big risk to rely on rain indefinitely.

As for distilling enough water, where are you going to get enough firewood to keep a fire going? Even if you could maintain an operating still on a tossing ship.



Other risks were not well known at the time of Columbus because no voyage had ever gone out of sight of land for so long. One of these was scurvy due to the lack of vitamin C. Also, in tropical waters shipworms quickly ate away ship's hulls so they had to be beached and re-caulked periodically. You couldn't do this at sea. In fact, on Columbus's last voyage all his ships became so wormy on his return from Panama he had to make land in Jamaica, then only inhabited by Indians, rather than Hispaniola where the colony was. He was shipwrecked there for more than a year before he was rescued.

Last edited by Colibri; 10-23-2007 at 04:12 PM..
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Old 10-23-2007, 04:29 PM
Chronos Chronos is offline
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It's not so much that folks ever thought the world was flat, as that some folks just didn't care about the question at all. In the Middle Ages, if you asked an educated fellow what the shape of the world was, he'd tell you it was a sphere. But if you asked an uneducated fellow, he wouldn't say "flat"; he'd say "I dunno", and go back to his plowing. It's only the modern ridicule associated with believing in a flat Earth that puts it into the consciousness of modern uneducated folks, but many people are still ignorant of other, equally basic, facts of astronomy.
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Old 10-23-2007, 04:45 PM
Arnold Winkelried Arnold Winkelried is offline
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Thanks for the great info, Colibri, but I fell compelled to comment on one of your statements here.
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Originally Posted by Colibri
Other risks were not well known at the time of Columbus because no voyage had ever gone out of sight of land for so long.
*cough* Polynesians? *cough* I knew that they had colonized the Pacific Islands far before the Europeans ventured across the Atlantic, but I didn't know exactly when, so I did a quick Google search and found this:
http://sscl.berkeley.edu/~oal/background/polyhist.htm
Western Polynesia (Tonga, Samoa etc.) colonized around 1000 BCE
Eastern Polynesia (Cook Islands, Marquesas, Hawaii, Easter Island, New Zealand) colonized from 500 BCE to 1000 AD

I grant that the Polynesian sailors didn't go over to Spain and tell Ferdinand II and Isabella their secrets, but what did they know that the Europeans didn't? Is it because they had smaller crews?
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Old 10-23-2007, 05:31 PM
Colibri Colibri is online now
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Quote:
Originally Posted by Arnold Winkelried
I grant that the Polynesian sailors didn't go over to Spain and tell Ferdinand II and Isabella their secrets, but what did they know that the Europeans didn't? Is it because they had smaller crews?
No, it's because the distances between most island groups is much much smaller than across the Atlantic.

If you look at a map, you will see that most of the island groups are only a few hundred miles apart at most:

http://www.supertravelnet.com/map/1/61_0_3.jpg

The Polynesians mostly didn't have to make very big jumps. Some more distant groups were probably colonized initially by chance rather than deliberate exploratory voyages. And wave patterns and the flight of birds could give clues to the existance of islands far beyond the horizon. But the greatest voyages were something like less than a third that of Columbus.

The Atlantic where Columbus crossed is a good 3000 miles across. It is of course is a bit narrower between Brazil and Africa but nobody knew that.

Recent research also suggest that the Polynesians weren't quite as good as had been thought:

http://www.abc.net.au/science/news/stories/s1726137.htm

ETA: I should say that when I said no voyage had gone out of land for so long I meant no European voyage. Polynesians may have been at sea for longer periods on occasion, but rarely if ever deliberately. As you surmise, smaller crews would find it easier to subsist on fish but water would still be a problem.

Last edited by Colibri; 10-23-2007 at 05:35 PM..
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Old 10-23-2007, 11:06 PM
Colibri Colibri is online now
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Just a followup on the difficulty of making a large ocean crossing in Columbus's time. Magellan was the first to complete the voyage to Asia that Columbus had planned. It took the expedition 98 days to sail from the Straits of Magellan in southern South America to Guam, a distance of about 8000 miles. They somehow missed almost all the islands that dotted the Pacific on the way, hitting only two small atolls with no good anchorages. They lost 30 men to scurvy en route, and many were on the edge of starvation by the time they arrived. Magellan had a much more accurate idea of where the "Indies" were than Columbus, but he underestimated the distance as well. Even though they were better equipped than Columbus, they almost didn't make it.
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Old 10-24-2007, 12:15 AM
DrDeth DrDeth is offline
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Quote:
Originally Posted by Arnold Winkelried
This is probably a stupid question, but I'll venture to ask anyway.

When experts were telling Columbus he couldn't take enough supplies for his trip, did they mean food or drink?
If it was food, why couldn't the sailors catch enough fish during the trip to supplement their supplies enough to complete the trip? Drag a net behind the boat and haul it up twice a day.
If it was drink, I imagine it would be hard to distill enough salt water during your trip for everybody on board.
Fresh water was a big problem, and so was scurvy.

On a 15th century sailing ship, pretty much they didn't distill any water. Even if they had the technology, they couldn't carry enough fuel.
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Old 10-24-2007, 06:54 AM
MarcusF MarcusF is offline
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Quote:
Originally posted by Don't fight the hypothetical:
So the experts knew but did the average Joe in 1492 think the world was flat or round?
Going back to the OP I think the problem is defining "the average Joe".

As others have already alluded to there was a much sharper divide between the "educated" and the "uneducated" and the proportion of those with a decent eductation would have varied from place to place. I don't know about Genoa or Castile but in England schools were being founded in the 15th century - available free or at low cost to all local boys - but the big increase in grammer schools wasn't until the 16th century so the "educated" man would have been pretty rare in the years before Columbus sailed.
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Old 10-24-2007, 07:13 AM
Contrapuntal Contrapuntal is offline
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FWIW, some average Joes today are not convinced that the world is round.

http://www.youtube.com/watch?v=ZgF3pu9085w
YouTube video with sound.
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Old 10-24-2007, 09:11 AM
Xema Xema is offline
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Quote:
Originally Posted by Arnold Winkelried
When experts were telling Columbus he couldn't take enough supplies for his trip, did they mean food or drink?
As others have noted, they meant both. It was a considerable challenge to keep a crew healthy on a long voyage. The necessary knowledge wasn't gained until the late 18th century - and Capt. Cook's empirical understanding of how to prevent scurvy was slow to catch on.

There was no practical distallation of seawater on sailing ships - this had to wait for steam power.
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Old 10-24-2007, 11:27 AM
Napier Napier is offline
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If the question is asked, instead, "How sharply curved is the Earth", then it's pretty difficult to answer that it has a nonzero curvature, based on the kinds of local observations I can think of doing.

That bit about ships visually disappearing downward as they sail away - when is that true? Whenever I see ships on the ocean, as they get further away they become indistinct. It's not always apparent which of several horizontal lines and gradations is the horizon. Of course, the effect should happen geometrically, but as a real visual effect how many people here can say they've witnessed it?
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Old 10-24-2007, 11:58 AM
Xema Xema is offline
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Quote:
Originally Posted by Napier
That bit about ships visually disappearing downward as they sail away - when is that true? Whenever I see ships on the ocean, as they get further away they become indistinct. It's not always apparent which of several horizontal lines and gradations is the horizon. Of course, the effect should happen geometrically, but as a real visual effect how many people here can say they've witnessed it?
I've seen it thousands of times - it's essentially always apparent when the visibility is decent. Sailors routinely speak of a ship being "hull down" - you can see the upper part, but not the hull.
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Old 10-24-2007, 02:01 PM
Colibri Colibri is online now
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Quote:
Originally Posted by Napier
If the question is asked, instead, "How sharply curved is the Earth", then it's pretty difficult to answer that it has a nonzero curvature, based on the kinds of local observations I can think of doing.

That bit about ships visually disappearing downward as they sail away - when is that true? Whenever I see ships on the ocean, as they get further away they become indistinct. It's not always apparent which of several horizontal lines and gradations is the horizon. Of course, the effect should happen geometrically, but as a real visual effect how many people here can say they've witnessed it?
I've seen it many times, as I am sure have many other people who have spent any time on the sea. It is not just ships, of course - when you are approaching land from the sea, if there are any hills or mountains you will see the peaks first. This is quite obvious. I'm sure that in Columbus's time mariners at least would know that the Earth was curved, if not a globe.
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Old 10-24-2007, 02:11 PM
Gfactor Gfactor is offline
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Here is a picture of a globe, from right around 1492: http://www.henry-davis.com/MAPS/LMwebpages/258.html

The accompanying monograph notes:
Quote:
Globes in his age, and even earlier, were by no means unknown. Giovanni Campano (fl. 1261-64), a distinguished mathematician of Novara, wrote a Tractus de Sphera solida, in which he describes the manufacture of globes of wood or metal. Toscanelli, when writing his famous letter in 1474 (Slide #252), refers to a globe as being the best adapted for demonstrating the erroneous hypothesis as to the small distance which he supposed to separate the west of Europe from eastern Asia. Columbus, too, had a globe on board his vessel upon which was depicted Cipangu [Japan], and which may have been the work of his brother Bartholomew, who, according to Las Casas, produced charts as well as globes. But only two globes of a date anterior to the discovery of the New World have survived, namely this one in Nuremberg, and a smaller one at the DepŰt des planches et cartes de la marine, Paris
http://www.henry-davis.com/MAPS/LMwebpages/258mono.html
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Old 10-24-2007, 02:26 PM
Xema Xema is offline
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Quote:
Originally Posted by Napier
If the question is asked, instead, "How sharply curved is the Earth", then it's pretty difficult to answer that it has a nonzero curvature, based on the kinds of local observations I can think of doing.
Well, there's the fact that at a given latitude you get essentially the same view of the stars no matter what your longitude - the only difference being the time at which a certain view is available. Unless you postulate that those stars are really close (which has its own problems), it's hard to see how this could be true with zero curvature.
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Old 10-24-2007, 02:41 PM
matt_mcl matt_mcl is offline
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Quote:
Originally Posted by Napier
That bit about ships visually disappearing downward as they sail away - when is that true? Whenever I see ships on the ocean, as they get further away they become indistinct. It's not always apparent which of several horizontal lines and gradations is the horizon. Of course, the effect should happen geometrically, but as a real visual effect how many people here can say they've witnessed it?
You may be thinking of modern ships where the upper part of the superstructure is not substantially different in shape from the lower part, so it's hard to tell how much of the ship you're actually seeing. The effect would be more noticeable in a sailing ship with a tall mast or masts, which would remain visible after the hull disappears.
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Old 10-24-2007, 02:55 PM
SlowMindThinking SlowMindThinking is offline
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From what I've read, you should cut Columbus some slack. Agreed, pretty much everyone involved thought the world was round. The natural philosophers, or whatever they were called at the time, knew the dimensions pretty well.

But, Columbus was one of the greatest sailors ever. He based his estimate for the size of the earth on debris washed up along the coasts of Europe and Africa. His reasoning was impeccable. "Given this much unknown biological stuff, land isn't so far an expedition can't get there." IIRC, his estimate for the distance he had to sail wasn't too far off. He sold Isabelle on taking a chance on the distance, because of his evidence and reasoning. (He was also a great dead reckoner, but that is an aside.)

Of course, damn if I can remember where I read this.
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Old 10-24-2007, 03:09 PM
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IIRC Portugese explorers heading south along the coast Africa hit the point where the (northern) pole star disappeared below the horizon and the lack of that point hindered exploration. At any rate the non-visibility of Polaris and the northernmost stars in 1471 when the Portugese explorers crossed the equator would have most likely clued them in any case.
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Old 10-24-2007, 03:20 PM
Colibri Colibri is online now
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Quote:
Originally Posted by SlowMindThinking
IIRC, his estimate for the distance he had to sail wasn't too far off. He sold Isabelle on taking a chance on the distance, because of his evidence and reasoning.
His estimate of the distance to be traveled was way way off. He thought the distance from western Europe to Asia heading west was less than 3,000 miles, when it is actually about 11,000 miles. That's a pretty damn big error. It was only the fact that the Americas were where he calculated Asia to be that his expedition didn't end up an utter disaster or coming back without result.
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Old 10-24-2007, 03:58 PM
Don't fight the hypothetical Don't fight the hypothetical is offline
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Thanks for the link, Gfactor.
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Old 10-24-2007, 04:44 PM
Gfactor Gfactor is offline
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No problem. I'm currently working on a Columbus-related staff report. I had to look it up for that anyway.
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Old 10-24-2007, 04:54 PM
Arnold Winkelried Arnold Winkelried is offline
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Quote:
Originally Posted by Colibri
His estimate of the distance to be traveled was way way off. He thought the distance from western Europe to Asia heading west was less than 3,000 miles, when it is actually about 11,000 miles. That's a pretty damn big error. It was only the fact that the Americas were where he calculated Asia to be that his expedition didn't end up an utter disaster or coming back without result.
I thought that the point of SlowMindThinking's post was that Columbus was betting that there was a landmass not so far away. Columbus' mistake was thinking that the landmass was Asia when in fact it was the Americas. So he was wrong on the continent but lucky in his deduction, from the debris washed on European and African shores, that another landmass was not so far away. Now, if his deduction had a rational basis, that I don't know.
(This is of course assuming that what SlowMindThinking is saying has a historical basis.)
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Old 10-24-2007, 04:56 PM
Arnold Winkelried Arnold Winkelried is offline
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Originally Posted by Gfactor
No problem. I'm currently working on a Columbus-related staff report. I had to look it up for that anyway.
Link doesn't work. I keep on trying to rotate the globe with my mouse pointer but it won't budge.
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Old 10-24-2007, 05:02 PM
Arnold Winkelried Arnold Winkelried is offline
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Quote:
Originally Posted by Colibri
No, it's because the distances between most island groups is much much smaller than across the Atlantic.

If you look at a map, you will see that most of the island groups are only a few hundred miles apart at most:

http://www.supertravelnet.com/map/1/61_0_3.jpg

The Polynesians mostly didn't have to make very big jumps. Some more distant groups were probably colonized initially by chance rather than deliberate exploratory voyages. And wave patterns and the flight of birds could give clues to the existance of islands far beyond the horizon. But the greatest voyages were something like less than a third that of Columbus.
Thanks Colibri. Of course it's obvious when you point it out. One last question though - the Polynesians were travelling a third of the distance Columbus did, but were they travelling as fast? I imagine that Columbus' ships would travel faster than a Polynesian ship from 1000 AD. What were the Polynesian ships? Catamaran-type ships (I seem to recall reading that somewhere) or just big canoes?

This page (evgschool.org) says that Columbus' ships covered approximately 150 miles a day. I couldn't easily find an estimate for the speed of the Polynesian vessels.
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Old 10-24-2007, 05:06 PM
Gfactor Gfactor is offline
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Quote:
Originally Posted by Arnold Winkelried
Link doesn't work. I keep on trying to rotate the globe with my mouse pointer but it won't budge.
Rotate your monitor.
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Old 10-24-2007, 07:32 PM
Blake Blake is offline
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Originally Posted by Arnold Winkelried
the Polynesians were travelling a third of the distance Columbus did, but were they travelling as fast?
It would depend a lot on conditions, but on average they were probably travelling somewhat faster. The large ocean-going outriggers had much smaller sails than European ships but much a much shallower draw, so under conditions of light winds they would have moved faster. As wind speed increased the European ships would have gained the advantage. Outriggers also have a massive advantage sailing close to the wind, so if the voyage is running against prevailing winds the outrigger wil travel much faster.

Cook wrote of his one of his contacts with Polynesians that their large outriggers were quite literally sailing rings around him by alternating between just sails with the wind and supplmenting with oars against it.

Quote:
What were the Polynesian ships? Catamaran-type ships (I seem to recall reading that somewhere) or just big canoes?
Both, the vessels for long voyages were almost always outrigger canoes. They weren't strictly catamarans since they had only a single hull, but one or two logs were attached to that hull via poles to produce a very stable outrigger. Cloth was then stretched between the hull and the outriggers to provide extra storage space.

By using only a single hull to minimise contact with the water outriggers are much faster than catamarans of the same size.

Quote:
This page (evgschool.org) says that Columbus' ships covered approximately 150 miles a day. I couldn't easily find an estimate for the speed of the Polynesian vessels.
"Voyaging canoes in the Caroline Islands have reportedly made long passages at average speeds of as much as eleven knots and larger Marshallese canoes have been clocked at 16 knots. "

So at 11 knots that's about 303 miles/day if that speed can be maintained constantly, and about 150 miles/day if only sailing for 12 hours/day. The actual figure is presumably somewhere in between if we assume a high speed is maintained during daylight hours and a more sedate pace at night. Certainly comparable to Columbus' speeds.
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Old 10-24-2007, 08:43 PM
Walloon Walloon is offline
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Quote:
Originally Posted by Colibri
His estimate of the distance to be traveled was way way off. He thought the distance from western Europe to Asia heading west was less than 3,000 miles, when it is actually about 11,000 miles.
Could his error have been deliberate, to increase the apparent possibility and success of the voyage to his sponsors?
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Old 10-24-2007, 09:53 PM
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Quote:
Originally Posted by Walloon
Could his error have been deliberate, to increase the apparent possibility and success of the voyage to his sponsors?
No, unless you count deluding himself. As has been noted elsewhere, Columbus was a dyed-in-the-wool crackpot. He cherry-picked data to convince himself the voyage was possible. It is clear from his own log of the voyage that he expected to find land where he had calculated it to be - on September 25 he was in the vicinity where he thought a couple of islands should lie, and there was a false alarm that they were sighted. (In fact there were several such in the last weeks of the voyage.) In fact, Columbus deliberately falsified the information on distance he gave the crew, including the other captains, so they would not become too afraid and mutiny (which they nearly did anyway.)
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Old 10-24-2007, 10:26 PM
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Quote:
Originally Posted by Arnold Winkelried
I thought that the point of SlowMindThinking's post was that Columbus was betting that there was a landmass not so far away. Columbus' mistake was thinking that the landmass was Asia when in fact it was the Americas. So he was wrong on the continent but lucky in his deduction, from the debris washed on European and African shores, that another landmass was not so far away. Now, if his deduction had a rational basis, that I don't know.
(This is of course assuming that what SlowMindThinking is saying has a historical basis.)
Well, yes, to some extent. Apparently carved bits of driftwood and "sea beans" (the seeds of a tropical liana) sometimes washed up in the Azores, and this is one of the hints Columbus used to convince himself land was not too far away to the west. But this wouldn't allow him to predict very well just how far it was.
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Old 10-25-2007, 10:37 AM
SlowMindThinking SlowMindThinking is offline
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Quote:
Originally Posted by Colibri
His estimate of the distance to be traveled was way way off. He thought the distance from western Europe to Asia heading west was less than 3,000 miles, when it is actually about 11,000 miles. That's a pretty damn big error. It was only the fact that the Americas were where he calculated Asia to be that his expedition didn't end up an utter disaster or coming back without result.
I did not mean his estimate of the distance to Asia. I meant his estimate of the distance to land. Yeah, he thought the land was Asia. It doesn't seem to have occurred to anyone that there was land between Asia and Europe that was not known to either.
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Old 10-25-2007, 10:48 AM
SlowMindThinking SlowMindThinking is offline
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Originally Posted by Colibri
Well, yes, to some extent. Apparently carved bits of driftwood and "sea beans" (the seeds of a tropical liana) sometimes washed up in the Azores, and this is one of the hints Columbus used to convince himself land was not too far away to the west. But this wouldn't allow him to predict very well just how far it was.
My understanding was that he based his estimate on the quantities of various forms of debris. The weak part of all this is, of course, where did I read this? Given what I read, it was most likely an article in Scientific American, possibly in the Smithsonian , which my mom still got for a few years after my dad died, or American History, which my dad got. I suppose it could have been a National Geographic lying around somewhere. In any case, it was years ago, perhaps in 1992. Without dredging it up, it is hard to determine if the author wasn't a crackpot, himself.
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Old 10-25-2007, 12:40 PM
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Driftwood and other evidence from the Azores is mentioned in Samuel Eliot Morrison's biography Admiral of the Ocean Sea. However, he does not mention that Columbus made any estimate of actual distance because of this. Even if he had, there could hardly have been any real basis for it.
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