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Old 11-15-2008, 04:04 AM
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Did early explorers really worry that they might fall off the edge of the world?


You sometimes hear that European explorers in the 1400s or so were especially brave as they didn't even know if, in setting off across the ocean, they might drop off the edge of the world.. Was the belief that one could fall off the world ever very widespread, or have people more or less known for millennia that we live on a globe and can exist all over it without falling off if you are not "on the top" ?
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Old 11-15-2008, 04:43 AM
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My understanding is it was one of those things people had been theorizing for a long time, and most educated people already believed the earth to be round by the 1400s. But of course during that time, education was relatively scarce and there were still plenty of others squawking a lot of misinformation (hmm...) so basically some did, and some didn't.

Here's a cite that puts the first round-earth theories around 500 BCE.
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Old 11-15-2008, 05:28 AM
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You'd have to figure that the most enlightened thinkers of the time were only 99% sure that there was no edge out there, not having proven that fact empirically. Which would make them plenty brave, by my standard.

The contemporary analogy is the atomic scientists who couldn't be absolutely certain than a nuclear detonation wouldn't somehow set off all the atoms in the world to blow up in a chain reaction. I remember reading how late (1930s at least) some scientists were striving to show other scientists how this wouldn't happen, and it seems only logical that there were a few hardcore conservative thinkers who still found this a frightening possibility well into practical development of the first nuclear explosions.

There's a big difference between being 99% sure that something would end your life and being 100% sure. If you hand me a gun and tell me that there's one chance in a hundred it's loaded, I'm absolutely not going to fire it at my head, but if I've looked into the chambers and convinced myself that it's empty, I'll fire it anywhere I please.
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Old 11-15-2008, 06:33 AM
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They knew that the world was round. The classic example given is Columbus who bucked the conventional wisdom, not by insisting that the world was round, but by insisting that the earth's circumference was substantially smaller than most academics believed (The academics of his age were more correct than he was, which is why the West Indies were where he thought Indonesia would be.

Even if they didn't know that the world was round, the sailors and officers on their ships had probably figured it out after watching the land drop below the horizon on outbound voyages. Also, fishermen from Northern Europe had been fishing the Grand Banks for generations, landing in Nova Scotia occasionally. They had probably at least heard that there was land out there. Columbus, for example, may have gone on a fishing voyage to the Grand Banks (Sorry, but I don't have time to find links right now.)
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Old 11-15-2008, 06:34 AM
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They were 100% sure. Since the time of the Greeks it had been known that the earth was round. Our ancestors had eyes and common sense. Don't forget that the 'edge of the earth' would be the horizon, a mere 20 miles distant. Anyone watching a ship slowly sink from sight would have evidence enough of the earth's curvature.
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Old 11-15-2008, 06:56 AM
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The way I was taught it (a) agrees with what has been said for coastal cultures, like the Greeks, but (b) there was uncertainty about how far down one could sail without going off the edge. As I understand it, this is why Magellan's crew underwent a mutiny - for fear of sailing too far down and falling off the edge. (The idea of "gravity" hadn't caught on quite yet, I guess.)
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Old 11-15-2008, 08:24 AM
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Under "flat earth" Wikipedia suggests:
The common misconception that people before the age of exploration believed that Earth was flat entered the popular imagination after Washington Irving's publication of The Life and Voyages of Christopher Columbus in 1828. This belief is even repeated in some widely read textbooks. Previous editions of Thomas Bailey's The American Pageant stated that "The superstitious sailors [of Columbus' crew] ... grew increasingly mutinous...because they were fearful of sailing over the edge of the world"; however, no such historical account is known.[68] Actually, sailors were probably among the first to know of the curvature of Earth from everyday observations, for example seeing how mountains vanish below the horizon on sailing far from shore.

-- always assuming, of course, that Wikipedia can be trusted But it sounds plausible that it could have been a later myth based on assumptions that people were ignorant in those days. Would be interesting to know if it is in fact true that there is no documentation from the time to suggest such a fear on anyone's behalf

Anyway, thanks for the thoughts so far
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Old 11-15-2008, 08:42 AM
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Possibly attacking the question with a bit too much logic, but...

"If there's an edge of the ocean, then the water must constantly be falling off it in some gigantic cataract. Is there really enough rain falling on the ocean to keep the high water mark from dropping and dropping until the ocean is nearly all gone?"
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Old 11-15-2008, 09:37 AM
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Note that roundness and falling off the Earth were not completely distinct issues to the ancients. The Greeks had considered the idea of people living in the antipodes who hung upside down from tree branches. (Although "antipodes" means "feet opposite", so someone had a clue.) Ergo, some sailors may have thought that if you sailed far enough you might have slipped off the side of a round Earth.

There was no clear cut concept of gravity. Elements sought their own natural level. So the oceans may not have also flowed off due to the "fact" that water just didn't do that.
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Old 11-15-2008, 09:47 AM
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Originally Posted by aldiboronti View Post
They were 100% sure. Since the time of the Greeks it had been known that the earth was round. Our ancestors had eyes and common sense. Don't forget that the 'edge of the earth' would be the horizon, a mere 20 miles distant. Anyone watching a ship slowly sink from sight would have evidence enough of the earth's curvature.
I'm not sure how you'd be 100% sure of that.

The only thing I'd be willing tp accept, to settle the OP, would be some ancient documents that were absolutely contemptful of anyone who considered the possibility of being able to sail around the world. The kind of contempt that evolutionary biologists now have for creationist biologists would probably fall short of that absolute sense of haughty superiority that I'm requiring for 100% certainty. So: cite?
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Old 11-15-2008, 10:08 AM
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...some sailors may have thought that if you sailed far enough you might have slipped off the side of a round Earth.
I doubt it. Wouldn't that require the sea surface to slope away more and more as you got further away from the top of the Earth? Sailors, above all, would know that doesn't happen. The sea is always level.
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Old 11-15-2008, 10:58 AM
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But it sounds plausible that it could have been a later myth based on assumptions that people were ignorant in those days. Would be interesting to know if it is in fact true that there is no documentation from the time to suggest such a fear on anyone's behalf
Columbus did face a mutiny by his crew on October 10, but all his account says is:

"Here the people could stand it no longer, complained of the long voyage; but the Admiral cheered them as best he could, holding out good hope of the advantages they might have..."

Later accounts suggest that Columbus promised to turn back if they did not sight land in two or three days.

As far as I am aware, there was no suggestion that the crew was fearful of sailing off the edge of the world. They were apprehensive about being farther from shore than any other Europeans had ever been before, and worried by the extreme length of the voyage by contemporary standards; but they didn't see falling off the edge as a possibility.

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(b) there was uncertainty about how far down one could sail without going off the edge. As I understand it, this is why Magellan's crew underwent a mutiny - for fear of sailing too far down and falling off the edge. (The idea of "gravity" hadn't caught on quite yet, I guess.)
Magellan was also faced with a mutiny during the winter he spent in Patagonia, but it was for politcal and personal reasons, and had nothing to do with fear of falling off the edge.
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Old 11-15-2008, 11:02 AM
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I thought it was more a fear of the open sea stemming from the fact that the sophisticated equipment that enabled navigation away from visible land was pretty new.

Prior to the age of exploration, most sailing involved hugging coastlines, always being fairly close to land and frequent port calls. The first time you spend three months with nothing to look at but a huge flat expanse of ocean and no idea when you'll see land again, I could see being very afraid.
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Old 11-15-2008, 11:37 AM
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I doubt it. Wouldn't that require the sea surface to slope away more and more as you got further away from the top of the Earth? Sailors, above all, would know that doesn't happen. The sea is always level.
The laws of Physics as we know them weren't known back then. The small expanse of ocean that sailors generally travelled may not have suggested a global concept of level. God could always make things seem level until ... aaaayyh.
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Old 11-15-2008, 12:23 PM
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Possibly attacking the question with a bit too much logic, but...

"If there's an edge of the ocean, then the water must constantly be falling off it in some gigantic cataract. Is there really enough rain falling on the ocean to keep the high water mark from dropping and dropping until the ocean is nearly all gone?"
Not necessarily. Think of a tray full of water to the brim. There is an edge and you could fall of it (if you were the right size) but it is not emptying. Rain on it would cause it to overflow and create the traditional cataract effect of cartoons, but not empty it.
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but I digress

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Old 11-15-2008, 12:56 PM
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The laws of Physics as we know them weren't known back then. The small expanse of ocean that sailors generally travelled may not have suggested a global concept of level. God could always make things seem level until ... aaaayyh.
Educated persons knew the Earth to be round - Erathostenes and some of the other old boys had deduced not just that, but also the size of the earth, with pretty good accuracy.

Ptolemy even listed (not very practical) ways to compute longitude and latitude from observations. In the 15th century, if you bothered to think about it at all, you knew the earth to be round.

Columbus' challenge to the conventional wisdom of the time was his idea of the size of the Earth - and he was wrong.
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Old 11-15-2008, 01:00 PM
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The evidence of the horizon doesn't prove that the world is round, only that it's convex.
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Old 11-15-2008, 01:44 PM
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The contemporary analogy is the atomic scientists who couldn't be absolutely certain than a nuclear detonation wouldn't somehow set off all the atoms in the world to blow up in a chain reaction. I remember reading how late (1930s at least) some scientists were striving to show other scientists how this wouldn't happen, and it seems only logical that there were a few hardcore conservative thinkers who still found this a frightening possibility well into practical development of the first nuclear explosions.
Which atomic scientists were those? All of the ones working on the Manhattan project knew that wasn't possible, and I can't imagine that there were very many atomic scientists at the time who weren't working on the Project.

And no, they couldn't have been 100% certain that they wouldn't fall off the Earth, but then, we can't be 100% certain that we won't fall off the Earth, either. For all we know, there's a spot 122.7 miles east by northeast off the coast of the Azores where gravity works backwards for 17 minutes on every third Tuesday. But there's some level of certainty which is good enough for our daily lives.
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Old 11-15-2008, 01:58 PM
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Possibly attacking the question with a bit too much logic, but...

"If there's an edge of the ocean, then the water must constantly be falling off it in some gigantic cataract. Is there really enough rain falling on the ocean to keep the high water mark from dropping and dropping until the ocean is nearly all gone?"
It works for Terry Pratchett .

Also, Balthisar makes a good point.
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Old 11-15-2008, 02:19 PM
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Spiny Norman: You quoted my post but then discussed a whole other thing. Quoting the wrong person?
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Old 11-15-2008, 06:36 PM
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Columbus' challenge to the conventional wisdom of the time was his idea of the size of the Earth - and he was wrong.
Does anyone know why Columbus insisted the earth was smaller than generally agreed upon by the knowledgeable?
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Old 11-15-2008, 06:47 PM
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Does anyone know why Columbus insisted the earth was smaller than generally agreed upon by the knowledgeable?
Yes, because he was a crank with a pet theory.

Columbus theorized that it would be possible to reach Asia by sailing west. However, if the calculations of most people were correct, the distance was too far to be feasible to cover in the sailing vessels of that day. Columbus cherry-picked the available data to arrive at the conclusion that Asia was much much wider than most people believed, and that the circumference of the Earth was much smaller. This would make the distance to be sailed much shorter than it actually was, and possible to cover in the ships of the time. Coincidently, Columbus's calculated distance to Asia was just about the distance to the Americas.
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Old 11-15-2008, 07:14 PM
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Which atomic scientists were those? All of the ones working on the Manhattan project knew that wasn't possible.
"...the nuclear physicists [at Los Alamos on July 13, 1945]...knew they were taking a giant step into the unknown. The warnings to the 509th [Composite Groupof the 313th Wing of the 21st Bombing Command of the 20th Air Force, i.e. the Enola Gay's group] about lightning had not been fanciful. It was the one inponderable in equations. A stray bolt from an electrical storm could atomize all of them, and since the outer limits of a chain reaction were unknown, conceivably the entire planet might be destroyed. The weight of scientific opinion was against it, but no one could be sure."

--William Manchester, THE GLORY AND THE DREAM: A NARRATIVE HISTORY OF AMERICA, 1932-1972. Little Brown: Boston. 1974, pp. 376-7.
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Old 11-15-2008, 07:22 PM
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Manchester's source for this paragraph seems to be Karl T. Compton's article in the December, 1946 Atlantic Monthly. "If the Atomic Bomb Had Not Been Used."
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Old 11-15-2008, 07:31 PM
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There's also this:

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"The sphericity of the earth is proved by the evidence of ... lunar eclipses," Aristotle says. "For whereas in the monthly phases of the moon the segments are of all sorts--straight, gibbous [convex], crescent--in eclipses the dividing line is always rounded. Consequently, if the eclipse is due to the interposition of the earth, the rounded line results from its spherical shape"
Not sure if "proved" is the same as "100% certain" -- but it's probably pretty close for someone like Aristotle.
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Old 11-15-2008, 08:25 PM
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By 300 A.D., not only was the size of the Earth known pretty accurately, the size and distance of the sun and the moon had estimates that weren't that far off. If the Greeks of 300 A. D. had had reasonably accurate naked-eye measuring equipment, they would have known the size and distance of the sun and moon pretty accurately. Even with lousy measuring instruments, they did halfway well:

http://en.wikipedia.org/wiki/Aristar..._and_Distances

The fact that the Earth, moon, and sun are spheres was thus not only known, but that fact was used in further calculations.
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Old 11-15-2008, 11:49 PM
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"...the nuclear physicists [at Los Alamos on July 13, 1945]...knew they were taking a giant step into the unknown. The warnings to the 509th [Composite Groupof the 313th Wing of the 21st Bombing Command of the 20th Air Force, i.e. the Enola Gay's group] about lightning had not been fanciful. It was the one inponderable in equations. A stray bolt from an electrical storm could atomize all of them, and since the outer limits of a chain reaction were unknown, conceivably the entire planet might be destroyed. The weight of scientific opinion was against it, but no one could be sure."
It looks like this is warning that a lightning strike might trigger the bomb before it was released, and I don't know enough about the devices to say whether that's true. But there was already one tested at Trinity before they sent the bomber crews to Hiroshima and Nagasaki, and if there were any lingering doubt, that should have dispelled it.
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Old 11-16-2008, 07:35 AM
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It looks like this is warning that a lightning strike might trigger the bomb before it was released, and I don't know enough about the devices to say whether that's true. But there was already one tested at Trinity before they sent the bomber crews to Hiroshima and Nagasaki, and if there were any lingering doubt, that should have dispelled it.
I think the date I was referencing was the date of the test at Trinity, when the lingering doubts (that lingered IOW up until July 12, 1945) still lingered, which was my (or Manchester's) point: Until the thing had been done, there was always that shred of doubt.
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Old 11-16-2008, 07:44 AM
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Paintings of Columbus and other sailors of his day often show them holding octants (similar to sextants), navigation instruments that were somewhat emblematic of the sailing profession. These instruments measure location on the earth by measuring the elevation of astronomical bodies above the horizon. They should only work if the earth is round.

But I don't think it's obvious from the disappearance of tall items at the horizon as you move away from them that the earth is round (or more accurately convex, you're right). The times I have looked for this, things always disappear in an increasingly hazy and indistinct horizon while they are also getting smaller overall. I've never been able to tell that the lower parts of objects were actually disappearing from view, as opposed to shrinking towards but never dipping below an ideal horizon. I think this proof of the convexity of the earth is too hard to observe unambiguously to be useful.
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Old 11-16-2008, 08:02 AM
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I think the date I was referencing was the date of the test at Trinity, when the lingering doubts (that lingered IOW up until July 12, 1945) still lingered, which was my (or Manchester's) point: Until the thing had been done, there was always that shred of doubt.

Yes, Trinity was 7/13/1945. The point about lightning is incidental--the more germane point here is that there remained a question even in Manhattan Project physicists' minds that the A-bomb could set off a chain reaction that would destroy the planet. Even if only one or two of them (and Manchester implies that there were more) had doubts and fears, that's well below 100% certainty that a chain reaction would not occur.

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Old 11-16-2008, 09:22 AM
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Manchester's source for this paragraph seems to be Karl T. Compton's article in the December, 1946 Atlantic Monthly. "If the Atomic Bomb Had Not Been Used."
Compton's article is online. He was not at the Trinity test and the piece says nothing about lightning or the risk of a runaway chain reaction.
I haven't read The Glory and the Dream, but the quoted passage seems a bit garbled. There was a thunderstorm the night before the Trinity test that led to worries about the tower being hit, but the real concern there was either a partial detonation or, more likely, the surrounding electrical equipment being fried, either of which would wreck the test. However, the 509th wasn't running the test - and, offhand, I'm not even sure any of its members were present. (Various participants at Trinity did go on to join them on Tinian, but they were members of Los Alamos on secondment.)

There had been a debate amongst the physicists about a bomb triggering a runaway chain reaction in the atmosphere several years earlier, but Hans Bethe quickly showed that this outcome was exceedingly unlikely. Various people revisited the issue thereafter, but without overturning this basic conclusion. There is then some muttering in the hours before the test, but this is as much black humour as anything else.
It's true that nobody could be certain there was absolutely no risk, but there was agreement that it was acceptably minimal. It's sometimes been suggested, including by Richard Rhodes, that Robert Serber was significantly concerned the night before, but he explicitly claimed in his memoirs Peace & War (Columbia, 1998, p91) that his remarks at the time were jokes and that he thought there was no risk.

Manchester's remarks thus seem a garbled and exaggerated version of what actually happened - hardly an unknown occurance in that sort of popular history writing.

Furthermore, none of this should be confused with the popular perception in the Thirties that "splitting the atom" was somehow likely to end the world.
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Old 11-16-2008, 09:41 AM
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It's true that nobody could be certain there was absolutely no risk, but there was agreement that it was acceptably minimal.
I think "acceptably minimal" = "less than 100% certain," and my point is that if you're only 99% sure that you're not starting something that will destroy the planet immediately, you've got a pretty large set of balls. To get back to the OP, if you've got that same level of confidence that you're not going to sail off the edge of the planet into an endless abyss, I'll give you points for being the first one to try it. As I read Chronos's assertions of 100% confidence, it was a completely settled issue, and the only problem was technological, not whether the outcome was achievable.

I actually think the confidence level in both was less than 99% and the results have added to people's assessment of their confidence before the fact, but even 99% takes considerable guts.

Thanks for the link--I've always wanted to read Compton's article.
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Old 11-16-2008, 09:46 AM
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But I don't think it's obvious from the disappearance of tall items at the horizon as you move away from them that the earth is round (or more accurately convex, you're right). The times I have looked for this, things always disappear in an increasingly hazy and indistinct horizon while they are also getting smaller overall. I've never been able to tell that the lower parts of objects were actually disappearing from view, as opposed to shrinking towards but never dipping below an ideal horizon. I think this proof of the convexity of the earth is too hard to observe unambiguously to be useful.
Next time you're at the beach on a clear day, look at the ships (esp large ships or sailing ships). On the sea, it's really very obvious, and anyone who was familiar with ships at the time could have made the observation if he'd bothered to look.
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Old 11-16-2008, 10:00 AM
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And Manchester wasn't suggesting that the 509th was present at Trinity--just that they'd been given warning to avoid lightning storms on their test runs.
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Old 11-16-2008, 01:10 PM
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I didn't assert 100% confidence, because in science, there is no such thing. I can't be 100% confident that I won't accidentally destroy the world by scratching my nose. Despite a lack of 100% confidence, however, there is nonetheless a level of confidence beyond which one may say that one is certain of something. By the time of the Trinity test, all of the scientists involved were at that level of confidence.
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Old 11-16-2008, 01:16 PM
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Paintings of Columbus and other sailors of his day often show them holding octants (similar to sextants), navigation instruments that were somewhat emblematic of the sailing profession.
I have never seen such a painting but if any exist they are inaccurate as the octant was invented a couple of centuries after Columbus. In Columbus' time they used astrolabes and latitude could be determined by measuring the height of Polaris or by measuring the height of the sun above the horizon at the meridian crossing because tables of declination were already well known.
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Old 11-16-2008, 02:28 PM
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I have never seen such a painting but if any exist they are inaccurate as the octant was invented a couple of centuries after Columbus. In Columbus' time they used astrolabes and latitude could be determined by measuring the height of Polaris or by measuring the height of the sun above the horizon at the meridian crossing because tables of declination were already well known.
Columbus himself apparently never used even the astrolabe. His journal indicates he was unable to use his astrolabe on his first voyage, and there is no evidence he took one on any of his subsequent voyages. According to Morison in Admiral of the Ocean Sea (p. 184), "The common quadrant ... was the only instrument of celestial navigation that Columbus ever employed."
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Old 11-16-2008, 03:43 PM
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I can't be 100% confident that I won't accidentally destroy the world by scratching my nose.
You mean you'd do it deliberately?
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Old 11-16-2008, 03:49 PM
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Aren't quadrants, octants, and sextants all forms of astrolabe? In any event, the use of any of them to determine latitude requires the assumption that the Earth is round.
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Old 11-16-2008, 04:18 PM
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>Next time you're at the beach on a clear day, look at the ships (esp large ships or sailing ships). On the sea, it's really very obvious, and anyone who was familiar with ships at the time could have made the observation if he'd bothered to look.

I HAVE done this. That's why I posted what I have observed. I don't know how good your eyes are and how clear the horizons you've seen are, but I spend a week on the Outer Banks every summer and have had a few other visits to various Eastern and Western US beaches, and I swear it's never been clear that sailboats and other tall things moving toward or away from me are appearing or disappearing from the horizon up. I can't tell that there's a hull or a lower sail no longer visible while I can still tell there is an upper sail visible. Of course, I understand that that is what somebody ought to see if the air is clear enough (and if the gradient in air density is gradual enough, but that's another story). The point here is that, for at least some frequent observers, the sailboat disappearing from the bottom up is not clear.

And I've looked often and hard enough at water horizons to have seen a green flash once, and to have seen the sun rise over the Pacific twice (near Santa Barbara where the coast curves inward enough to allow this).
  #41  
Old 11-17-2008, 02:02 PM
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Quote:
Originally Posted by Chronos View Post
Aren't quadrants, octants, and sextants all forms of astrolabe?
No. A quadrant is an entirely different instrument.
Quote:
In any event, the use of any of them to determine latitude requires the assumption that the Earth is round.
True. There was zero doubt at that time among educated people that the world was round. Zero.

The question was the size and geographic distribution. The size was also known with a certain aproximation. The latitude difference between known geographical points was known with a reasonable accuracy and so the length of the degree was also known with a certain (rough) accuracy. Some would go with higher figures and some with lower. Columbus, like many people, not being immune to adjusting the facts to suit his purposes, proposed a very small world.

Another variable was the distance between Spain and Japan by way of the Middle East. No one knew with any certainty how many degrees of longitude that might cover and Columbus proposed high figures so that the remainder, the distance from Spain to japan going west would be small.

How much of that he really believed and how much of that was market8ing we do not know. probably there was a combination of all of it. He hd probably heard stories about land having been sighted to the NW Atlantic. Whether that was true or myth we do not know but he was probably influenced by it. He then tweaked the figures of longitude so they would fit his pre-concieved notion of where this land might be. And he assumed this land was Japan because no one had ever heard of anything else. He devised a selling plan which worked because it sold but we don't know how much he really believed.

Note that he also constantly lied to his crews about the distance being made good so that they believed they were not as far from Spain as they really were and so they believed they were closer and easier to get back home.

One thing is clear and that is tha Columbus knew very well the currents and winds of the Atlantic and navigated mainly by dead reckoning rather than by astronav.

But, yes, everyone knew the earth was round and no one really had any fear of falling off the edge. Their fears were much more real: in those times life at sea was tremendously unsafe and many who went never came back. But life inland was also very hard and people took risks that were unthinkable today.
Well into the 20th century life at sea was *very* risky and men were often lost overboard without much thought. Read any 19th century story about sailships and you will see what I mean.

In the National Geographic Magazine, in the February 1931 issue, there is an article by Alan Villiers titled "Rounding Cape Horn in a Windjammer". You can find it online.
Quote:
On the 38th day Walker was killed at his work in the rigging. It was very simple. Just one of those ordinary everyday accidents that nine hundred times kill nobody and on the 901st wreak vengeance on some innocent for their previous failings.
...
We were setting the fore upper topgallant sail,
...
When it was halfway up, the second mate saw that a gasket was foul on the weather clew. The sail would not hoist properly. He yelled aloft to Walker, through the rain, to go out on the lower topgallant yard to clear the gasket. Walker went and cleared it. He called down to us that everything was clear. We began to heave again. The halyards carried away and the yard came tumbling down.

It fell on Walker, beneath it, and killed him there.

We did not know that he was dead when we rushed up the mast and found him unconscious between the yards. We thought he was merely senseless. There was no sign of wound, save for some blood oozing slowly from his mouth.

It never occurred to us that he was dead; we were too much concerned with bringing him to and getting him to the deck that we might see the extent of his injuries and what we could do about them. I tried to bring him to with cold water that had been brought from the deck. I did not know how hopeless it was. We wanted to restore him to his senses in order that he might help us with the difficult task of getting him, from high on that swaying mast, to the deck. It was not easy to bring a senseless body down that slippery and pitching rigging.

But he did not come to. We rigged a gantline and lowered him down, gently, carefully.

When we got to the bottom, Captain Svensson took one look.

"He is dead," he said.
In 1893 the Spanish sailship "Nautilus" was sailing around the world when a sailor fell from the rigging and lost his life when he hit the deck.

In "Two Years Before the Mast" Dana writes:
Quote:
Monday, Nov. 19th. This was a black day in our calendar. At seven o'clock in the morning, it being our watch below, we were aroused from a sound sleep by the cry of "All hands ahoy! a man overboard!" This unwonted cry sent a thrill through the heart of every one, and hurrying on deck we found the vessel hove flat aback, with all her studding-sails set; for the boy who was at the helm left it to throw something overboard, and the carpenter, who was an old sailor, knowing that the wind was light, put the helm down and hove her aback. The watch on deck were lowering away the quarter-boat, and I got on deck just in time to heave myself into her as she was leaving the side; but it was not until out upon the wide Pacific, in our little boat, that I knew whom we had lost. It was George Ballmer, a young English sailor, who was prized by the officers as an active lad and willing seaman, and by the crew as a lively, hearty fellow, and a good shipmate. He was going aloft to fit a strap round the main top-mast-head, for ringtail halyards, and had the strap and block, a coil of halyards and a marline-spike about his neck. He fell from the starboard futtock shrouds, and not knowing how to swim, and being heavily dressed, with all those things round his neck, he probably sank immediately. We pulled astern, in the direction in which he fell, and though we knew that there was no hope of saving him, yet no one wished to speak of returning, and we rowed about for nearly an hour, without the hope of doing anything, but unwilling to acknowledge to ourselves that we must give him up. At length we turned the boat's head and made towards the vessel.

Death is at all times solemn, but never so much so as at sea. A man dies on shore; his body remains with his friends, and "the mourners go about the streets;" but when a man falls overboard at sea and is lost, there is a suddenness in the event, and a difficulty in realizing it, which give to it an air of awful mystery. A man dies on shore--you follow his body to the grave, and a stone marks the spot. You are often prepared for the event. There is always something which helps you to realize it when it happens, and to recall it when it has passed. A man is shot down by your side in battle, and the mangled body remains an object, and a real evidence; but at sea, the man is near you-- at your side--you hear his voice, and in an instant he is gone, and nothing but a vacancy shows his loss. Then, too, at sea--to use a homely but expressive phrase--you miss a man so much. A dozen men are shut up together in a little bark, upon the wide, wide sea, and for months and months see no forms and hear no voices but their own, and one is taken suddenly from among them, and they miss him at every turn. It is like losing a limb. There are no new faces or new scenes to fill up the gap. There is always an empty berth in the forecastle, and one man wanting when the small night watch is mustered. There is one less to take the wheel, and one less to lay out with you upon the yard. You miss his form, and the sound of his voice, for habit had made them almost necessary to you, and each of your senses feels the loss.

All these things make such a death peculiarly solemn, and the effect of it remains upon the crew for some time. There is more kindness shown by the officers to the crew, and by the crew to one another. There is more quietness and seriousness. The oath and the loud laugh are gone. The officers are more watchful, and the crew go more carefully aloft. The lost man is seldom mentioned, or is dismissed with a sailor's rude eulogy--"Well, poor George is gone! His cruise is up soon! He knew his work, and did his duty, and was a good shipmate." Then usually follows some allusion to another world, for sailors are almost all believers; but their notions and opinions are unfixed and at loose ends. They say,--"God won't be hard upon the poor fellow," and seldom get beyond the common phrase which seems to imply that their sufferings and hard treatment here will excuse them hereafter,--"To work hard, live hard, die hard, and go to hell after all, would be hard indeed!" Our cook, a simple-hearted old African, who had been through a good deal in his day, and was rather seriously inclined, always going to church twice a day when on shore, and reading his Bible on a Sunday in the galley, talked to the crew about spending their Sabbaths badly, and told them that they might go as suddenly as George had, and be as little prepared.

Yet a sailor's life is at best, but a mixture of a little good with much evil, and a little pleasure with much pain. The beautiful is linked with the revolting, the sublime with the commonplace, and the solemn with the ludicrous.

We had hardly returned on board with our sad report, before an auction was held of the poor man's clothes. The captain had first, however, called all hands aft and asked them if they were satisfied that everything had been done to save the man, and if they thought there was any use in remaining there longer. The crew all said that it was in vain, for the man did not know how to swim, and was very heavily dressed. So we then filled away and kept her off to her course.

The laws regulating navigation make the captain answerable for the effects of a sailor who dies during the voyage, and it is either a law or a universal custom, established for convenience, that the captain should immediately hold an auction of his things, in which they are bid off by the sailors, and the sums which they give are deducted from their wages at the end of the voyage. In this way the trouble and risk of keeping his things through the voyage are avoided, and the clothes are usually sold for more than they would be worth on shore. Accordingly, we had no sooner got the ship before the wind, than his chest was brought up upon the forecastle, and the sale began. The jackets and trowsers in which we had seen him dressed but a few days before, were exposed and bid off while the life was hardly out of his body, and his chest was taken aft and used as a store-chest, so that there was nothing left which could be called his. Sailors have an unwillingness to wear a dead man's clothes during the same voyage, and they seldom do so unless they are in absolute want.
These things were part of everyday life and they were accepted as such. Only in very modern times do we expect complete safety. And this only in more advanced countries. There are still many hundreds of thousands who would assume the risk of drowning or otherwise dying in exchange for a small chance of reaching a developed country where they will have better life prospects. Many are dying every day in this pursuit.
  #42  
Old 11-17-2008, 02:14 PM
sailor is offline
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Quote:
Originally Posted by Chronos View Post
Aren't quadrants, octants, and sextants all forms of astrolabe?
To expand a bit on this. A quadrant is an early instrument as is the astrolabe and they both work by direct sight.

An octant is a much later reflection instrument and the sextant is a modified for of octant (the octant covers 90º and the sextant 120º).

Froma wikipedia page to which I contributed long time ago
Quote:
http://en.wikipedia.org/wiki/Navigational_instrument

Celestial navigation instruments - These instruments are used primarily to measure the elevation or altitude of a celestial object:

Back staff, the best known of which is the Davis' quadrant. It could measure the altitude of the sun without having the navigator directly observe the sun.

Cross staff, an older instrument long out of use.

Kamal Very simple instrument used primarily by Arabian navigators. It consists of a small board with a knotted piece of twine through the center. The observer holds one of the knots in his mouth and extends the board away so that the edges make a constant angle with his eyes.

Mariner's astrolabe Derived from the astrolabe, it was developed in late 15th century and found use in the 16th to 17th centuries. It was replaced by the back staff and later by the octant and sextant.

Quadrant A very simple instrument which used a plumb bob.



These instruments are also used to measure the angular distance between objects:

Octant, invented in 1731. The first widely-accepted instrument that could measure an angle without being strongly affected by movement.

Sextant, derived from the octant in 1757, eventually made all previous instruments used for the same purpose obsolete.

Bearing instruments
Pelorus used to determine bearings relative to the ship's heading of landmarks, other ships, etc.


Compasses
Bearing compass used to determine magnetic bearings of landmarks, other ships or celestial bodies.

Magnetic compass used to determine the magnetic heading of the ship


Timekeeping
Marine chronometer used to determine time at the prime meridian with great precision which is necessary when reducing sights in celestial navigation

Nocturnal used to determine apparent local time by viewing the Polaris and its surrounding stars.

Ring dial or astronomical ring used to measure the height of a celestial body above the horizon. It could be used to find the altitude of the sun or determine local time. It let sunlight shine through a small orifice on the rim of the instrument. The point of light striking the far side of the instrument gave the altitude or tell time.

All those mentioned were the traditional instruments used until well into the second half of the 20th century. After WWII electronic aids to navigation developed very rapidly and, to a great extent, replaced more traditional tools. Electronic speed and depth finders have totally replaced their older counterparts. Radar has become widespread even in small boats. Some Electronic aids to navigation like Loran have already become obsolete themselves and have been replaced by GPS
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