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Archimedes Death Ray in San Francisco
Monkey-Man2000 writes "Following the recent demonstration by MIT students that Archimedes' death ray could have been used to burn Roman ships, the producers of the Discovery Channel's Myth Busters invited the MIT team to San Francisco to try their death ray on an 80-year old fishing boat. This time, even with perfect weather, they were unable to set the boat afire. From the article, "Peter Rees, executive producer of "Myth Busters," said the experiment at the Hunters Point Shipyard showed that Archimedes' death ray was most likely a myth.""
...if they had properly powered it with cold nuclear fission.
Sheesh, evil *and* a jerk. -- Jade
Looks like getting someone's pants on fire was not the pastime in Archimedes's day.
The height of conceit: having an orgasm and calling out your own name.
Why are they trying to burn the wood, when it seems like the rigging should be easier to torch and just as debilitating?
7 November 2006: The day Americans realized corruption and incompetence weren't addressing 11 September 2001
Couldn't they have just burned the sail and let it burn down the rest of the ship? As I know, cloth burns much better then wood ;)
Life is not for the lazy.
Having failed to do the experiments once and declare the thing as "most likely a myth"! Even today, many, if not most, of the experiments are non-replicable. Well, for most cases they are probably myths or hoaxes, but some of them are genuinely very hard to replicate. The reason can range from precision requirements to hazy details. The latter is the usual suspect, which, I believe, applies in this case as well.
--
Error 500: Internal sig error
This thread needs more pictures of Kari...
...wait, wrong website. :-P
I take it as a sign that if Syracuse had the entire MIT instead of one Archimedes, we would not be hearing the story at all. Go Greeks.
So... it sometimes works, but is generally not reliable enough for anyone to bother reusing it. The Greeks lost that battle, too -- if the death ray worked well, they could have just burned everything (at least until the evening came).
The story sounds plausible. Archimedes invented something that managed to set one or two ships on fire (and most likely the fire was extinguished in no time), but was unable to have any strategic meaning.
The creatures outside looked from Alt-Right to Antifa; but already it was impossible to say which was which.
mythbusters just did it wrong. http://www.solardeathray.com/
Accept any challenge, No matter the odds.
I wonder if Roman ships may have been innately more flammable than that 80 year old boat. The use of tar or pitch to seal rough-hewn planks on the sides of the Roman ships would have made them more susceptible to fire. Any oiled cloth would also have made these ancient boats more flammable.
Two wrongs don't make a right, but three lefts do.
"I couldn't do it, therefore it cannot be done"? These guys need to go back to logic 101.
"Hyneman has a degree in Russian language and literature. He has had a variety of careers, including scuba diver, wilderness survival expert, boat captain, linguist, pet shop owner, animal wrangler, machinist and chef."
"Adam Savage: Before becoming a TV host, he spent 10 years as an artisan in special effects, specifically modelmaking for companies such as Industrial Light and Magic, Warner Bros. and Disney. He worked on such films as Star Wars Episodes I and II, The Matrix sequels, Bicentennial Man, A.I., Space Cowboys, and others.
He has also been an animator, graphic designer, carpenter, set designer, toy designer, rigger, and has many sculptures on display in museums across the country."
http://en.wikipedia.org/wiki/Adam_Savage
http://en.wikipedia.org/wiki/Jamie_Hyneman
As others have mentioned, we don't know what the Roman boats were exactly made of. Was it pine? Balsa? And the tar/pitch used to seal them is very flammable.
The time of day is important; the amount of solar energy hitting the mirrors is highest at noon.
They could have lit the sails, which is good enough when you're trying to set fire to a wooden boat.
Modern boats have paint and all sorts of other goodness on them, which is reflective.
This boat that they tried this experiment on was 80 years old. What does years of sitting in water do to the wood, in terms of flammability? We don't know. How old were the ships that Archimedes set on fire? We don't know.
Now we know that SQ of distance effects the power
No, dissipation of light in air is negligible on such distances, so the power itself is roughly constant. The effect of distance is all in targetting inaccuracies -- having a number of soldiers pinpoint a distant object exactly is not really feasible.
The creatures outside looked from Alt-Right to Antifa; but already it was impossible to say which was which.
Freshmen from MIT used some scrawny wood not representative of the thickness of an actual vessel of that age. Thinner wood burns more readily, eh? The myth doesn't mave much more math to it than a good highschool education would impart. Are you pissed because your tuition is so expensive?
Blar.
The anti-personnel aspects of the Archimedes Heatray were probably more important.
Imagine being a rower and this intolerable heat builds up on your back.
Or a steersman or bowman? Sighting in the glare?
Burning the rigging would be a plus, but disabling the enemy crew would be better. In fact it would be the equivalent of a neutron bomb, leaving the boats to be used by the Greeks at a later date whilst killing off the enemy!
There's more than one way to skin a cat!
Spreading rumours about Archimede's marvelous machines must have been a pretty good deterrent to invasion.
Remember that 7-Up commercial from a couple'a years back? The one that features a 7-Up machine on treads that rolled around and fired cans of soda at people?
Jamie built that.
His company, M5 Industries Inc., specializes in robotic designs for visual effects. He's got a lot of experience building, you know, robots. He's designed or been involved in designing things that are required to do a huge variety of bizarre and wacky things - from the aforementioned surly soda-firing vending machine robot to a motorized shoe-cycle to a articulated giant hand (as seen in the film Monkeybone).
And, to remind those of you who watched Battlebots when it was on:
He built Blendo.
So, yes, he's got engineering experience. He's got a lot of engineering experience. And, yes, special and visual effects work *does* require a lot of skill and talent - and the ability to judge whether something is practicable in the field.
(I'd also recommend that you look at the career of one James "The Amazing" Randi before commenting further. Take an especially close look at how often people claim that a stage magician shouldn't be trying to debunk so-called "real" paranormal events.)
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Ant(Dude) @ Quality Foraged Links (AQFL.net) & The Ant Farm (antfarm.ma.cx / antfarm.home.dhs.org).
As a picky guy, I noticed a space. It is "MythBusters". See the official Web site. No space! Also, no Mythbusters.
Ant(Dude) @ Quality Foraged Links (AQFL.net) & The Ant Farm (antfarm.ma.cx / antfarm.home.dhs.org).
The fact is that the mythbusters guys often engage in poorly constructed 'experiments' which a scientifically literate person would recognize as being inadequate for the purposes in question. Many of their efforts are laughably incomplete or rely on misunderstandings of the phenomena that contibute to whatever they're testing.
No gods, no demons, and no masters. Secular Humanism!
Early Roman navys were often temporary entities although there were also permanent squadrons even during the later empire. By then it seems their main function was to combat pirates and smugglers since the Romans had by then eliminated all serious naval challengers. A large standing navy only reappeared during the very late imperial and Byzantine period when various barbarian and large moslem naval forces reappered as the Western and then the Eastern Roman Empire collapsed. The temporary fleets, built on campaign or to deal with some sudden maratime threat, were often built of unseasoned or low quality wood and intended to last no more than a few of campaigning seasons before they were either scrapped as unseaworthty or had been lost to bad weather. While it is probably possible to torch a Roman war galley at ancor on a calm cloudless day using some sort of mirror array I don't think such a weapon would have scored more than a couple of sucesses at best and it would have been practically useless against a fast moving and maneuvering target. It would have been most useful against relatively immobile targets such as floating siege towers or catapults that would have been mounted on platforms made by lashing several galleys together. If anything the psychological effect of this 'death ray' would have been far greater than the practical destructive effect, sort of like the effect that rockets had the first time Chinese armies deployed them in combat. At first they probably scared the hell out of the barbarians but after a short while barbarians got wise to the fact that unless they were really big and carried exploding warheads Chinese rockets were not terribly destructive and made sure their forces knew it and that the horses were acclimatized to the alien noises the rockets made. I would not expect a force that achieved the very high degree of professionalism the Roman army did to have been impressed by this sort of a weapon for very long even if the weapon worked under ideal conditions.
Only to idiots, are orders laws.
-- Henning von Tresckow
We cannot build something that compares to the size and accuracy of the pyramids in Egypt, using only the materials and tools they had available at the time. Although we know for a fact they managed it somehow.
Just because we can't replicate it, doesn't mean it can't be done.
C17H21NO4
In those times, it must have been something quite scary.
Let's see, you're on a boat, going into battle. Everybody's naturally quite nervous already. And suddenly there's this really awful light that sets fire the sail, sets somebody's hair on fire, burns another one's face, blinds several people... The Greeks would probably not get it perfectly right on the first try, but could in the process manage to freak everybody out even before getting any practical results.
I bet that even without burning anything you could cause enough confusion with just blinding and burning people to make everybody on the boat think that the sky is falling. Nobody would want to dare look towards the light, so it could make things quite complicated.
Hi.... It's my first post here..... I really like this site! Now.... The other thing to remember is that at the time of Archimedes, good quality glass was not discovered yet - most mirrors at the time were made from malachite. Such a mirror would not have reflected nearly the amount of light that a modern glass mirror would have done. Good quality glass did not come into Rome until about 250 years after Archimedes. I actually looked into this pretty carefully for my book "The Light of Alexandria" - http://www.lightofalexandria.com/ . Some of the other inventions that Archimedes made for the defense of Syracuse were pretty amazing, though........ JM
Why are they trying to burn the wood, when it seems like the rigging should be easier to torch and just as debilitating?
Gives new meaning to the phrase "rigged test", eh?
As the other link hints of, generally battle ships of those days depended on manual rowing far more than sails during battle because sails were not that fast back then.
But an alternative explanation is the Archimedes' techniques could have been used to blind and confuse the occupants during battle. Not nearly as dramatic, but still possibly a way to get an edge. The myth of torching could have grown out of that.
Table-ized A.I.
After attempting and failing to reconstruct the pyramid of Cheops, experimenters conclude that "the fabled Pyramids of Egypt are likely just a myth, there's no way they could have built such a huge pile of stone slabs when we with our mighty technologies cannot do so today."
What exactly is your idea of "a lot farther north"?
Both San Francisco and Syracuse (Italy) are both between 37 and 38 degrees north latitude.
Perhaps they should call themselves the "Mythtesters", rather than the "Mythbusters". The process they use does not lend itself to definite conclusions. They merely test the plausibility of such myths. As such, I don't think they should make the claim that they "bust" the myths.
Cyric Zndovzny at your service.
5 second rule? What are you a barbarian? Where I come from it's 3 seconds. 5 seconds is just insane.
Arbitrary sig
"If you investigate paranormal events with the mindset that it's all fake, then you're just as bad as the `true believers' you're trying to discredit. Scientific exploration of anything requires an open mind."
Oops! Mind the deep philosophical waters there. Now you've splashed truth all over yourself; let's try to dry you out a bit.
The history of the philosophy of science (a mouthful were there ever one) is complicated, and I think that it's fair to say that there's no widespread agreement on the exact details of what science is. A popular view, however, is that it proceeds in three parts. First, a hypothesis is developed. The hypothesis should be precise, predictive, useful, and falsifiable. Second, the most rigorous possible attempts are made to falsify the hypothesis. Third, as attempts at refutation fail, the hypothesis gradually becomes an accepted theory, meaning that others will build new hypotheses atop it. Of course, the theory could still be falsified at any time; if so, a new hypothesis is created by adjusting or discarding current theory, consequences of the change upon other hypotheses and theories are evaluated, and the process begins again.
A variant of this process particularly popular in modern science is known as "statistical hypothesis testing". The basic idea is to reject the "null hypothesis" that no effect of some action exists by statistically testing the data. "Failure to reject the null hypothesis" triggers rejection of the contrary hypothesis that an effect exists.
By these definitions of what science is, it really only "requires an open mind" in the hypothesis formation stage. In the hypothesis testing stage, it requires the exact opposite: intense efforts to falsify ("debunk") the hypothesis. In this view, Randi is quite credibly a scientist, and real scientists debunk things all the time.
There. Looks like that was dry enough to do for you. March on!
This is why you don't put your faith in freshmen (or 1/3 of the stuff in medical journals, but that's a separate issue).
Fair enough but the MIT team did achieve ignition using fixed mirror placements and just 127 flat 1 square foot mirrors.
The 'freshmen' failed because there was no visual reference point for aiming. When 100 other 'bright spots' are aiming at the same target you, there is no way of telling which bright spot is yours so it's impossible to make the proper adjustments to focus your beam onto the target.
So, the only real constraint is providing a means of manually aiming the mirror properly. I'm not an optics expert...but if there's a way to design a sighting device, perhaps like a sextant, then the myth of 3000 soldiers with 5'-square bronze shields incinerating a ship could easily be true.
(1 square foot)X127=127(MIT achieved ignition with this, roughly 1100 F)
vs.
(5 square feet)X3000=15,000(Grecian army w/ bronze shields)
That's a massive magnification factor of about 120X. 120X the ignition luminance(cd/m2) could vaporize the target instead of igniting it.
The government has a defect: it's potentially democratic. Corporations have no defect: they're pure tyrannies. -Chomsky
When completed in 1978, the National Solar Thermal Test Facility cost just over $21 million. The NSTTF is an array of 222 focusable mirrors, or heliostats, covering 8 acres (7 football fields), located on the grounds of Sandia National Laboratory at the edge of Albuquerque, New Mexico.
The mirrors (facets) are focused onto a receiver or target mounted on a tower. The NSTTF tower is 200 feet tall, and its 8-foot-thick foundation is 50 feet below ground. The mirrors can direct up to 5 megawatts of solar radiation onto the receiver or other experimental objects. An uncooled object placed in the beam can be quickly raised to temperatures of over 4000 degrees F.
The mirrors are mounted on individual frames that are tipped up and down and rotated east to west by small motors much like those used in electric clocks. The motors are controlled by a computer which determines how to position each heliostat so that its reflection hits the receiver at any time of the day and any day of the year. The mirrors are made of two layers of glass with reflective silver between the glass layers. The quality of the glass is like that in your windows at home. The silver in one heliostat (25 mirrors-in one frame) weighs only about 1 ounce. Rain, snow, and other natural forms of moisture actually help keep the mirrors clean by washing away accumulated dust. Hail and dust storms have not harmed the mirrors. Only hail over 1 inch in diameter is likely to break the mirrors.
Atleast they do use some science, and do apply reason in most, if not all myths they deal with.
Anyway, they just create a TV show, and I find their scientific curiousity and readiness to try out things appealing. and that they are not full of any deep religeous/mythological sh**.
Experience in building stuff and making things work take them high above most couch scientists and technoblabbers anyway.
My first thought back when watching the originalepisode was pretty simple: Hold something (preferably colored glass) infront of your mirror. Your bright dot will be the colored one. Bonus points for a unique stained glass design you can use so multiple people can aim at once, but once you start coloring them you can fix your aim and move on to the next guy within 30seconds.
Pain lasts, kid. Its how you know you're alive. Sometimes I think this growing up thing is just pain management-TheMaxx
Such as? I think Mythbusters is one of the best science-related programs on tv today. No not because all of the shows are done with an exacting precision and logical rigorousness reminiscent of the Cavendish lab, but rather because it shows the core of the scientific method IN ACTION. They have an idea that needs testing, they make a guess at what might happen if they try X, they build an experiment to actually try X, then they run the experiment and draw some conclutions from the results. I can not recall a more apt application of the Baconian method ever being shown on any TV show (save for perhaps Bill Nye or Mr. Wizard or something). Who cares if thier guesses about how precisely the experiment should be set up are wrong, that's (a HUGE) part of science! At the end of the show they usually even discuss where thier experiments could've gone wrong or what might be done better if they tried it again. What more could you ask for in a tv show?! I think it is an especially excellent show for kids to watch. Numerous scientific principals are explained in an accessable and interesting manner (bouyancy, properties of heat and light, mechanical levers and mech. advantage, electrical circuts, flamability of vapours vs. liquids, properties of density, inertia, and on and on). The show can do a great job of keeping them simultaneously entertained with the odd explosion but also teaching the rigorous and logical thought processes necessary for the foundation of a scientific mindset. I really can't say enough good about it.
- "Hear that?! The percolations are imminent! Cease your ingress!"
The MythBusters *frequently* come into experiments with preconceptions. Have you ever watched the show?
Furthermore, I suspect you miss the point. The point is that people often don't understand the appropriate skill-set required to test particular claims. In Randi's case, because a significant portion of what he's been asked to test involves fraud and trickery (Uri Geller's amazing spoon-bending sleight-of-hand, Peter Popoff's Holy Radio Transmitter, the kids who can change the color of a match in a matchbox, but only if you turn your back and don't tape the matchbox shut) the skill-set of a stage magician applies. In the MythBusters' case, much of what they're asked to do involves recreating (or creating) particular oddball scenarios in front of a camera, and, since the profession of practical visual effects artist can best be described as "recreating or creating particular oddball scenarios in front of a camera," that skill-set applies.
In other words, you don't need to be an optical engineer with eighteen patents and tenure at MIT to be able to point a lot of mirrors at something. You do have to, however, be able to point a lot of mirrors at something.
Randi doesn't even pretend to be unbiased.
Why should he be? No one has ever managed to offer up a single shred of empirical evidence that magical powers are real. Oh, excuse me: the vogue 21st century term is "psychic", I guess so you don't sound so much like a stupid twat when you claim that magic is real and that you can, indeed, cast spells.
There's no reason to treat magic as a heretofore unexplored branch of science since no one, anywhere, has ever managed to do anything magic as evidence that the paranormal exists. People who claim to have these powers are either fooling themselves, fooling other people, or doing both.
Given the complete and utter lack of this evidence, Randi's approach is perfectly reasonable. Especially since Randi has a perfect, 100% track record of debunking this crap as what it is: delusion and con artistry.
Max
My god carries a hammer. Your god died nailed to a tree. Any questions?
http://en.wikipedia.org/wiki/Global_dimming says that the earth has dimmed 'only' 5% globally since the 50's. Nice try, don't forget to turn in your geek badge on the way out!
I'd also like to see somebody try to take my badge for not cross-checking my wikipedia results with some other source. Go on, have at you!
The US is considerably further north than where this would have originally have been used. "The Med" is so much closer to the equator that the sun's rays hit it much more directly and thus will generate more heat/power. Plus during this time of year in the S.F. Bay area, it's relatively cool getting down to as low as 45 degrees. Plus the sun is at a much greater angle than if it were during the summer. On top of that, there's a constant cool breeze blowing off the water which will pretty much cool anything off extremely quickly. You can expect an extremely rapid cool down on just about anything in these conditions and it takes much more heat to accomplish the same job.
I don't mean to belittle anything that's been done thus far, but the bay area is a cold place when along the waterfront...even during the summer. Mark Twain once said the coldest winter he ever endured was the summer he spent in San Francisco. Since combustion is directly related to heat, and the amount of "power" generated from the sun's energy would be considerably greater if you get a more direct path, it would seem to me that it's possible to do this in the right conditions.
Besides, I don't really hold too much stock in the Myth Busters anyway. They aren't scientists, they're special effects guys, and I've seen several myth's they've busted that I've seen happen.
And, really, we are talking about Archimedes here. If there was one guy in the whole Ancient world who could successfully pull something like this, it would be him. I for one believe that he actually did it.
your awesome logic and irrefutable arguments have completely convinced me sir. thank you for setting me straight. i wish all slashdot posts were as well reasoned and concise as yours.
Actually no, it is not 120x it is more like 24x. You'r 5ft square shield would produce a "bright spot" that is 5ft square, not 1ft square, so you would actually have 3000 spots that cover 5ft square (assuming the shield is almost perfectly flat). So your magnification actually becomes 3000/127 = ~24
Every shield I have ever seen is actually convex in shape, which would actually disperse the light being reflected. Granted, you could reverse the shield to make it concave, which would concentrate the light. However this would make the range at which the light could be concentrated in any significant amount very limited - so if you wanted to burn a ship, it would have to be at within a specific range to achieve any sort of concentration.
Add this statement of yours:
The 'freshmen' failed because there was no visual reference point for aiming. When 100 other 'bright spots' are aiming at the same target you, there is no way of telling which bright spot is yours so it's impossible to make the proper adjustments to focus your beam onto the target.
Plus the fact that even the best polished bronze would be less efficient than a modern mirror, and the death ray probably just made the Romans see alot of pink dots for a while (or gave them a good tan).
If there's any truth to the story, then what probably happened was they all lined up their shield, blinding the crew, and some archers got a couple of good shots in with flaming arrows.
dnuof eruc rof aixelsid
Grant Imahara has a background in electrical engineering. I believe he is the only one with an engineering background. Most of the members of the show worked on Hollywood blockbusters and approach busting the myth, not in purely scientific method, but something close to it. Something like what you would do in middle school. Which is why the show is popular among non technical people as well as the techinial people.
The Mit people saw the original show and tried to do it their way. That is why Mythbusters people invited them to San Francisco, to show the differences between the Mit people and the Mythbusters. It's not critiquing, Mythbusters unlike any TV show I know respond to criticisms to their techniques and follow up on them, and I think that's a good thing.
MIT seems to have done well in this year's Head of the Charles Regatta. Reports of opposing crew shells bursting into flames have been dismissed by experts as "pure myth", but spectators were annoyed to find that all of the good viewing locations on the Harvard Bridge were occupied for the duration of the event by MIT mechanical engineering students.
It does decrease with the square of the distance from the source, but the source is the sun, not the mirror. Adding a few hundred feet to that distance will do very little change, even when squared.
The sun takes up .5 degrees in the sky. The light hitting the mirror from the "top" of the sun is not coming in parallel to the light from the "bottom" of the sun. There is an angle of .5 degrees. If the mirror were a point then at 100 feet the dispersion (in feet) would be approx. d= 100 * tan (.5) which is .87 feet. Now move to a 1 sq ft mirror. The top of this mirror is going to reflect light from the top of the sun down by .25 degress and light from the bottom of the sun up .25 degrees. Similar logic applies to the bottom of the mirror. So the light from the top at 100 feet is off of parallel by 100*tan(.25) or .436 feet and same for the bottom. This gives a height of 1.87 feet. Now do the same for the sides of the mirror and you get 1.87 for the sides so square it to get 3.49 square feet. Now the light in the central square foot is going to be more intense, but you are getting dispersion at 100 feet due to the angle of the sky that the sun occupies. BTW, the MIT site agrees with my math if you care to look it up.
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