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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.
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).
Rank my idea: http://www.sinceslicedbread.com/node/531
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.
Indeed, as far as I know the Mythbusters have very little scientific or engineering background. One was a marine, a pet shop owner, and a Hollywood stunt coordinator, was he not? And I believe that the other was an actor. I would imagine that their other minions were also actors and actresses before coming onto the show. Do they have any real experience and credentials that would suggest they are worthy of critiquing the work of people from MIT?
Cyric Zndovzny at your service.
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.
It's not a dupe at all.
The original article is discussing MIT's attempt. This article is discussing Mythbuster's failed attempt.
Same experiment, two different experimenters.
Cyric Zndovzny at your service.
"I couldn't do it, therefore it cannot be done"? These guys need to go back to logic 101.
They where using 300 sq ft of mirrors to set fire to a boat. They actually set fire boat at 75ft, so I call it a PASS. At 150ft they got smoke.
Now we know that SQ of distance effects the power so at 75ft there was 4 times more light/heat hitting a sq in of boat.
So that would suggest that 1200 sq ft would be needed for a fire at 150ft. Or use a different mirror that can cause a tighter beam.
Wrong. This is not a dupe.
/. article]
/. article]
/. story is about the MIT experiment, the latter is about Myth Busters.
First, the Myth Busters claimed the story about Archimedes is a myth.
Second, some guys from MIT managed to reproduce the death ray. [->a
Third, the Myth Busters made another experiment as a rebuffal to MIT. [->this
The former
The creatures outside looked from Alt-Right to Antifa; but already it was impossible to say which was which.
Because San Francisco has a climate soooo similar to Mediteranean Syracuse!
"While conditions were nearly perfect Saturday -- clear skies and almost no wind -- Wallace said moisture in the old boat's wood prevented the vessel from catching fire. " So, if you were a boat floating in the ocean, there wouldn't be any moisture allowing the ship to still, maybe, catch on fire...?
Ryan - http://www.thecosmotron.com/
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.
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!
Point it at passing cars' windshields.
Click here or here.
Spreading rumours about Archimede's marvelous machines must have been a pretty good deterrent to invasion.
More general info >t ents.html
http://www.mcs.drexel.edu/~crorres/Archimedes/con
~jennifer.k~
> 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?
Like a great big low-tech laser pointer to shine in the pilot's eyes?
Sheesh, evil *and* a jerk. -- Jade
"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." The ants in my backyard don't agree. They say my magnifying glass absolutely excists.
that it was used in warfare. Would a enemy ship hang around not moving all day? I don't think so. And the mirrors way-back-when weren't as good as the ones used in this experiment, and the boat they burned wasnt wet from sea water. Think about that for a second.
public class null extends java applet { System.out.print ("Tabula Rasa"); }
Click here!
Ant(Dude) @ Quality Foraged Links (AQFL.net) & The Ant Farm (antfarm.ma.cx / antfarm.home.dhs.org).
They blinded them to death
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).
I can't do it, I can't comprehend how it could happen, therefore it is Magic!
Blar.
Is it a myth or just the toy we wish existed? Bigfoot is a myth, the 5sec rule is a myth, this is different, it's the toy we all wish we had, really, who wouldn't want a solar powered death ray?
F7 doesn't work, ignore spelling and grammar
Ok so maybe I don't know how to spell her name, but that Scottie on Mythbusters is hot.
Like Greek goddess hot.
If she was on the boat, it would have caught fire. Causing all of her clothing to be burned off.
Leaving her naked, tattooed goddess body bare to all, blinding the eyes of the MIT students who have no conception of what she could be.
I want to see more Myths about Scottie not being my one day loverslave.
-----
sorry. I don't know what came over me there.
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
While they are quite entertaining, they lack any scientific background at all and mostly 'wing it'.
Many of their 'failed' projects are in fact doable. But not without some real skills and knowledge in that particular field that they are working with at the time.
But still, its a cool show and fun to watch.
---- Booth was a patriot ----
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
...on British TV in the last few years. Granted the ship was 18" long, but she burned good.
"Ancient myth turns out to be a myth, film at XI"
From the old book: "...and owing to the thickness and smoothness of the mirror he ignited the air from this beam and kindled a great flame, the whole of which he directed upon the ships that lay at anchor..."
Was it merely a mirror device, or did he use a combustible fluid? The ancient description, if the wording translates accurately, seems to indicate that he set the air on fire, then directed that fire at the ships. The ancient Greeks certainly had no petroleum, but did they have access to other combustible fluids?
Find environmentally and socially responsible products on http://buy-right.net
Even slashdot is slpping... the rain just keeps on fallin'
Why don't they use a lift to place them in the path of the sunlight then bounce a laser off the mirrors to properly align them?
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.
The problem is they conducted the experiment in SF... Here in Fresno during the month of July, things just occasionally burst into flames on their own... no death ray required.... :)
td
hard core geek-ware
The deathray was used on sails. It torched them, preventing the ship a fast escape from shore. Besides - wood in water is hard to ignite -- its in a sea of coolant.
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.
Nah.... They use common sense which is sorely laking in this whole discussion. The problem is with the time. Even MIT proved that the time it takes for them to get the device working is far too long for it to be practical. I could sit on the ship and chuck rocks at the death ray and screw them up all day long. Even if the mirrors didn't break Im gaurenteed that they the mirror was now knocked out of focus. If I truely wanted to be mean I'd kill them with a bow and arrow and ensuring that the death ray would never work because no one would be there to focus it.
Ooo man the floppy drive is broken. No wait. The computer is just upside down.
This is about a rather old episode of MythBusters... I don't believe it should be considered news.
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."
slightly offtopic but could not resist: Whether the Mythbusters have much experience or indeed degrees in science and/or engineering does not matter; they bring interesting topics about science and engineering to your average TV-watching Joe Sixpack and/or kids, which is very honorable.
Different regions of California have very different climates, depending on their latitude, elevation, and proximity to the coast. Most of the state has a Mediterranean climate, with rainy winters and dry summers.
So, aside from actually going to the Med, California is one of the closest places you can test something like this within the US.
If however,a single experiment yields the result,then it shows that" It can be done".The failure of the successive experiments does not necessarily invalidate the success of the expt.Coz it has been done!
Why does yahoo do this
Yeah, but then the Romans would complain that the Greeks weren't abiding by the Geneva Conventions, and Archimedes would be tried as a war criminal.
One cannot properly repeat experiments if one does not have the basic knowledge necessary to comprehend what the experiment is about. It may be the case that the Mythbusters do not have the necessary background to truly understand the experiments they are performing. Neither did the people at MIT as odd as that sounds. They forgot the one variable that if taken out probably ensured the myth would have worked and that is water. They forgot to cover the ship was to ensure that it was moist. You try setting fire to something that is slightly wet.
Ooo man the floppy drive is broken. No wait. The computer is just upside down.
That comes out the day after I have the winning bid for the Archimedes Death Ray on eBay.
That's our life, the big wheel of shit. - The Fat Man, Blue Tango Salvage
Olive Oil. The Greeks had lots and lots of Olive oil.
[Fuck Beta]
o0t!
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.
No, seriously, consider that Greece lies in part of the world getting a lot of sunshine. If they want definitive result, they should match try it near the place Archimedes did it.
The result might be quite different. Especially if it seems to be borderline case.
The moon is not fully subjugated. I demand a second assault wave preceded by a massive nuclear bombardment.
Self-deprecating entertainers on television show featuring staged explosions and other juvenile stunts have declared an MIT student experiment invalid. Makes sense to me.
We all know that a bunch of kids at MIT, and the morons at Mythbusters (who have been repeatedly shown to routinely fuck up their experiments) are just the people to prove that the guy who was most likely the single most brilliant human being in history (given his engineering ability, the materials he had to work with, and the fact that he wasn't "standing on the shoulders of giants") was wrong. Why, next week, maybe Mythbusters and some elementary school kids will disprove Einstein's Theories of Relativity!
Big difference there, my chum.
"We're not saying it can't be done," Rees said. "We're just saying it's extremely impractical as a weapon of war."
Bend the rules, control the environment and get whatever result you want, as the MIT experiment demonstrated.
People don't even read the Slashdot articles anymore?
Well... Its not possible to set up moist wood on fire, but its very probable that the sails were set on fire using the death ray.
yeah, but this show aired at least 6 months ago
They got ,Archimedes, screwed
Better is the enemy of good enough. - Russian proverb.
"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!
There's a big difference between focusing 200 mirrors on a single spot for 3 hours on the roof of a building, and focusing on a single spot for 2 hours while the target is sailing on rolling seas.
It may be possible to do this under very controlled circumstances, but doing it in the midst of battle is completely different.
First off all the folks out there ranting about sail cloth...
As the story goes I'm assuming it was used from the shoreline against anchored Roman ships. To that effect you wouldn't have sails deployed on an anchored ship so you have one hell of a hard target to hit. Secondly we aren't talking about burning the QE2 here you have one hell of a small target bobbing up and down in a harbor to hit with that focused beam of light from as someone mentioned before a 300 sq ft. mirror that you have to keep focused on a point.
Basically my point is that this may be plausible, and may have been tried, its battle effectivness was probably nil.
Now as far as effectiveness on water in naval vs. naval combat.
Not many sails on a Quinquereme (or Trireme) would be deployed in combat because the main source of power would be the 300 (less on a trireme) or so oarsmen (at least as Polybius's numbers go).
Secondly the Greek tactic of the day would be to RAM the opponents ship bellow the waterline and pull back and let it sink.
Not much time on the MOVING vessel on the POSSIBLEY calm water (not to mention the disruption to the waters surface by 200+ ships each with a large number of oars) to focus 300sq ft. or so (as someone said earlier) of mirror on a sail an effective distance away. Let alone the fact you are trying to dodge other ships trying to ram you.
Finally this brings me to my last point of it probably wasn't to effective as a combat tool against Roman naval tactics which basically were as described by Polybius to come in close to the enemy ship with intent of boarding it and locking it in with the Roman ship to turn the great naval battle into one large land battle on a man made island. The advantage of Roman prowess in close quarters land battles, and the fact they were facing Greek naval men unskilled in hand to hand combat led them to victory against the Greek navy on a rare occasion. The whole point of the device to set fire tot he enemy ship would be little deterrent to someone who's entire tactics were to get off of his ship to begin with and on to yours.
Not to leave the Greeks out they were still the better seamen and the romans would be hard pressed to catch them in their more maneuverable ships. More likely the scenario was 1. roman ship moving sluggishly toward smaller swift Greek ship. 2. Greek ship speeds up and goes to ram Roman ship. 3. Greek ship rams roman ship and before they can pull away Romans board the Greek ship through a bunch of different methods and then a land like battle ensues between Greek oarsmen and a contingent of battle hardened well trained (sea sick) Roman Legionaries.
Anyways to fully test this you would need two Triremes or Quinqueremes or one of each manned by oarsmen, and then you would need them on relatively calm and probably warm waters with both or one approaching the other with intent on ramming/boarding.
Before all that though you would have to get in Mr. Peabody's way back machine to find out how to build a friggen Quinquereme or Trireme to Greek or Roman Standards.
Then you can mount your 300sq ft. mirror to it and try aiming it on water in a relatively small boat by todays standards moving with the power of a bunch of oars. Also, don't forget that you are scared to death of the big Roman ship loaded with pissed off legionaries who haven't been home in 5+ year or more to see their wives children and farms, and who probably haven't eaten very well or been paid in weeks. Not to mention the arrows, ballista bolts, and general long distance mayhem of the time period all trained on that big glowing this thats making the pissed off legionaries boat hot.
-special shout out to Prof. Dixon who forced me to read Polybius
-and I guess to those other bastard prof.s who bailed and left me stuck in ancient history courses this semester.
-Oh and of course my mom
-oh and that Kari (Keri?) chick is uber hot
- and never forget OSCAR!
Well, technically I suppose it would be a death pyramid, but I still wouldn't want to stick my hand in front of it. Fried a penny in under 30 seconds. Strangely enough, it wouldn't make so much as a mark on an old hard drive casing.
My apologies- I know i'm probably violating some sort of unwritten rule by linking to my own site. I don't mean to be flame bait. This Slashdot story inspired me, so my summer project was to build a death ray. Anyway, here it is.
I wonder if they took into consideration the difference in latitude and the global dimming factor. A recent study shows that less light is actually making it to the ground in modern times (5% reduction between 1960 and 1990).
That said, I personally believe that it is a myth - getting all the mirrors at the right place at the right time with the proper coordination just wouldn't happen.
Advice for my fellow geeks: before seeking out that threesome you dream of, you might see what a TWOsome is like first.
Everybody involved with this seems to be making an unwarranted assumption:
That something described by witnesses thousands of years ago as a mirror-like device was a mirror.
Note that it is described as being made of "bronze or glass".
And that it was "thick", and that this was put forth as part of the reason for its effectiveness.
Giant magnifying glass, anyone?
Or potentially a mirror/magnifying glass combination, allowing various rotations so that the user is able to direct highly concentrated rays of light towards whatever he wants.
Several years ago a team of British engineers and academics designed, tested and refined their attempt at recreating the ancient Greek flamethrower. Once happy with their recreation they decamped to Greece, mounted the device on a fishing boat and successfully tested it on a modern copy of one of the invading vessels.
The whole design through testing process was captured by documentary cameras and made into a film shown on either Discovery Channel UK or, IIRC, UKTV Documentary. If I find links I'll post a follow-up later.
Ever been to Greece? In the summer? I have and it's fricken hot 110-115 def F. I don't recall seeing clouds ever. This is in sharp contrast to S.F. where people are wearing windbreakers, and clouds are everywhere. To do the test justice they need to build a pine/cedar boat caulked with pine tar and try this in the Greek isles where it took place.
..........FULL STOP.
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.
there leaders are like ours have been for 25 years. That is, they may just make up things to make themselves sound good or to validate what they do, i.e. this may be a political myth.
Has anyone relized that many boats back then had a very large amount of sawdust and tar between the planks? I didn't see that on the test ship, and I'm sure it wasn't on the old boat in the boatyard. Also what about the effect of using rough timber which would leave more surface area open to heat up quicker. I think that the tests could have been a little more representetive of the times back then.
Walk with me or walk behind.
Just because people today can't reproduce it does not mean it did not happen. Since we don't know exactly how he did it back then.
Did they happen to have lots of polished shields? Do they know the weather or how hot it was back then?
There are tons of factors that can make it happen, tons of factors only he could figure in.
I RTFA but not the 175 posts:
An old wooden fishing boat is going to be covered in thick marine paint and as the article said it was water logged.
Ancient Roman boats were caulked along the planks with pitch and cloth (and lime?). The sails were most likely wool or cotton and probably treated to be water resistant. There is likely to be oil in quantity on at least some of the galleys. A good argument can be made that Roman ships were significantly more flammable than a (relatively) modern wood fishing boat.
I wouldn't put anything past Archimedes, as well.
Josh
gigantino.tv - Heavy but weighs nothing.
I don't follow the logic from 'students playing with mirrors in the fall sunshine in San Francisco got bored and went to Ghiradelli Square' to 'an ancient Greek army could never have accomplished this'.
These anti-spam words aren't human-readable, by the way.
First off, we've all played with - or at least watched someone else play with - magnifying glasses before, burning leaves or torturing ants, haven't we? This is the same idea. What happens when you do that is that the lens refracts the sun's rays so that they focus into a small point on the material where it gets very hot. If you leave it there for an hour or so (assuming there's enough sunlight and no wind) you could probably even burn, say, a notebook or something else that's flammable.
Now if you use a bigger lens, you can capture even more of the sun's rays, meaning that the material will get hotter quicker. Seeing as Archimedes probably used a lens AT LEAST 50-100x bigger, he probably could've roasted the whole anthill in the time it takes us to kill just one ant. Also, as the project's FAQ says, the ships probably would've been anchored while attacking, so Archimedes would've had all the time in the world to burn the ships - they weren't going anywhere, so he wouldn't have had to refocus the lens or anything - and he probably built quite a few of these machines and had maybe 10-20 Death Rays all focused on different ships and just checked up on each one every couple hours or so. Or made it so that all of them focused on the same point on the ship and therefore all worked together as one "super Death Ray" (imagine a Beowulf cluster of Death Rays! :) ).
Also, magnifying glasses have a lens for MAGNIFYING things, not burning them. Different lenses will refract the light in different ways, and I'm sure Archimedes not only knew this but also found a way to calculate EXACTLY what the ideal curve of the lens would be.
Second of all, things were different in Archimedes' time. I've read that the Earth may actually be slowly moving away from the sun - if that's the case, then maybe a couple thousand years ago the sun was closer. Maybe it gave off more energy, too - this also would've given Archimedes an advantage.
Third of all is, once again, the very bad assumption that we're smarter than Archimedes. I'm sure there are a few things Archimedes knew that we don't - maybe some things he knew that only he knew and he didn't tell anybody else. I could easily see why he wouldn't want to give away any secrets about the Death Ray - if you found a way to fry a boat like that, would YOU want to risk your enemies finding out how?
www.linuxpenguin.net
I agree with the comments above regarding burning the rigging--much more likely than burning the hull. Seems to me it would only have taken two or three swipes with the "death ray" to figure that out.
My idea though--altered slightly from that above--is that clothing burns even easier than thick canvas. So burn anyone that comes on the deck of the ship. The advantage of doing this would be that the Greeks could keep the roman ships in the end.
Yep, just as I predicted, MIT was wrong. You now I used to want to transferr their after I finished where I am now, but with stuff like this happening all the time Im not sure.
Clearly your are stupid. There is no other explanation.
"Archimedes (a notably smart person) constructed a burning glass to set the Roman warships, anchored within bow and arrow range, afire."
He was smart enough to make a death ray, but not smart enough to shoot flaming arrows?
Sure, just head out there and add more mirrors.
Who cares that the ships are only 150 feet away and shooting arrows at you?
Who cares that the difference between smouldering and flaming is more than a few degrees?
Who cares if the mirrors required are unwieldy and easily targeted?
And they didn't know Archimedes was one of the greatest inventors of all time at that time.
This test was rigged in a very positive direction. It had good mirrors, the ship was stationary and not defending itself. It still didn't work.
I think you're missing another form of skepticism here. This system is just impractical. We know this can be done with large enough mirrors and a good tracking/controlling system. That can be proven pretty easily. The question is, could the system be used and manipulated practically at that time?
The answer seems to be no.
http://lkml.org/lkml/2005/8/20/95
So, Greek shields were convex, which means the inside of the shields were concave. The myth is that the Greek soldiers polished the inside of their shields to use for the "Death Ray". Concave mirrors have the lovely property that they focus light. This seems like it is crucial to the whole myth, yet neither the Mythbusters nor MIT used concave mirrors.
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!
(/disclaimer: not a historian, failed history at school, no idea what time of year Archimedes was supposed to have done this...)
Now they need to stick some people in the boats, wave the concentrated sunlight on some hair and skin (not just wood,) see how it affects the real combat situation.
peace slashdottaz.. don't be comin' down wit de harsh moddin' mon
Hi
From the previous article they set one mirror and then uncovered each of the other mirrors individually to aim them.
The man who trades freedom for security does not deserve nor will he ever receive either. - Benjamin Franklin
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.
...construct and successfully test 'Aggie Solar Death Ray' on jet-skis, and ski-boats.
October 22, 2005
College Station, Texas (AP)
By Spock the Baptist (The Fishing Physicist)
This weekend members of the Texas A&M Bass Club struck a blow for bass fishermen everywhere, when they successfully tested a solar death ray based on the 'myth' of Archimedes' death ray. The 'Aggie Solar Death Ray' targeted three different models of jet-skis, and two models of ski-boats and summarily destroyed them.
Upon hearing of the highly successful test Ray Scott, and Forest Wood held a joint press conference to reveal that they had contracted with the "Bassin' Aggies" to market the device through Bass Pro Shops to bass anglers the world over. This was immediately followed by a ring endorsement of the National Outdoor Writers Guild in a press statement. The Guild statement concluded that the 'Aggie Ray' was the greatest advance in fishing in the past half century.
Numerious stock analysts rated all stock related to the new invention an enthustic 'put up your kids for collateral!' investment.
"Oh drat these computers, they're so naughty and so complex, I could pinch them." --Marvin the Martian
Am I the only one that doesn't care? There's been at least 3 slashdot articles on this. Enough already.
The Jamie and Adam do indeed have "engineering backgrounds". They do "engineering" for a living, as several people have pointed out by now.
If you could only take the time to at least check the facts before posting you would at least come across as somewhat reasonable, CyricZ. As it is now you are just spewing out posts at an alarming rate, and usually making completely obvious comments, or you are missing the point or spreading misinformation as in this case.
I had to say it. I've got plenty of karma, so I'll take my chance here in the hope that more people discover what kind of person Cyric is. Just look at the amount of comments he makes!
Clever signature text goes here.
There's poo everywhere!!!
Even if this thing did work, wouldn't a simple bucket of water completely nullify it's deadliness?
I would look at the concept and knwoing it was difficult I migh do something like put oil in the water and ligth the oil, using the scare tactic that I can set ships on fire if they come
Androk
The MIT kids did manage to burn some wood boat replica. Here's the video of successfully burning a model. It's an interview with the faculty member that setted up the experiment. It shows that it actually was possible, if not practical, to burn something using mirrors.
This was on the October 20th episode of Daily Planet a daily science news show on the Canadian Discovery channel. A show worth watching if I can say so myself. You can basically see it all a few days later on the web.
There is a simple way to aim mirrors that you learn about in Boy Scouts.
Use a double-sided mirror with a hole in the center of it. Get the mirror in approximately the right position so that you can see the target through the hole, and in the backside reflection you can see on the ground where the Sun shines through the hole.
Tilt the mirror so that the sunlit point on the ground is (in the backside reflection) at the location of the hole, and so that you are still looking at the target through the hole.
If you draw it, remembering how mirrors reflect equal angles incidence and reflection, you can see that this shines the sunlight right at your target.
Easier to draw than describe, and easier to do than draw.
In the show, they proved that you could light something on fire, but you would have to have real good aim, or you would have to be very close for it to set something on fire. The proved this on the show with that mirror array, they got in real close and bam the thing caught fire...
Now, if you read the MIT group's FAQ/Paper, they say "100 feet was the biggest space we had"
If a freaking naval battle ship of any kind was within 100 FT, whats the freaking point of the mirrors... that and wouldnt someone on the boat say, "WTF are they doing with those mirrors?" promptly followed by another person saying, "shoot them!" (you damn well know you would attack people holding mirrors 100 ft from your boat.)
MIT this has to be the second biggests Fuck up by MIT students, I forgot the first but it was way more retared. Damn kids dont even know how to plagiarize.
"1+1=3 when using large values of 1"
Dropping a dummy down an N-floor elevator to see if 'jumping' at the last second decreases the damage to the dummy, i.e., increases you chance of survival if you are ever caught in a falling elevator.
If you call this "making a guess at what might happen if they try X" , when X is so absurd, it's no longer science or education - it's entertainment.
If there was an airbag at the bottom of the shaft in that particular experiment, I'd charitably call it pseudoscience.
I wonder: if you are aiming at something that is suddenly getting extremely hot, won't that point on the boat also be incredibly bright? i.e. isn't there a serious risk to the person doing the aiming?
'Myth' is a word that is overused as a pejorative in the English language, describing something that it was never intended to describe. It's silly... when we can just use the word "misconception" or "lie" or "deception" or "falsehood," or a half dozen other words, but instead use the word "myth" because it sounds better. When someone uses the word in this fashion, they make light of the greatness of actual mythology.
I understand that the gentlemen on the show are knowledgeable or experienced, but do they have to be such asses all the time?
The Admin and the Engineer
Mythbusters attempt and fail to land on the moon, then issue the following press release:
.. the next time you're out in the backyard exercising your Second Amendment rights, the liberals will see it! These satellites are sensitive enough to tell the difference between a Colt .45 and a .38 Special! And when they detect you with a firearm, their computers cross-reference the address to figure out your name, and then an enormous database housed at Berkeley is updated with information about you.
It amazes me that so many allegedly "educated" people have fallen so quickly and so hard for a fraudulent fabrication of such laughable proportions. The very idea that a gigantic ball of rock happens to orbit our planet, showing itself in neat, four-week cycles -- with the same side facing us all the time -- is ludicrous. Furthermore, it is an insult to common sense and a damnable affront to intellectual honesty and integrity. That people actually believe it is evidence that the liberals have wrested the last vestiges of control of our public school system from decent, God-fearing Americans (as if any further evidence was needed! Daddy's Roommate? God Almighty!)
Documentaries such as Enemy of the State have accurately portrayed the elaborate, byzantine network of surveillance satellites that the liberals have sent into space to spy on law-abiding Americans. Equipped with technology developed by Handgun Control, Inc., these satellites have the ability to detect firearms from hundreds of kilometers up. That's right, neighbors
Of course, this all works fine during the day, but what about at night? Even the liberals can't control the rotation of the Earth to prevent nightfall from setting in (only Joshua was able to ask for that particular favor!) That's where the "moon" comes in. Powered by nuclear reactors, the "moon" is nothing more than an enormous balloon, emitting trillions of candlepower of gun-revealing light. Piloted by key members of the liberal community, the "moon" is strategically moved across the country, pointing out those who dare to make use of their God-given rights at night!
Yes, I know this probably sounds paranoid and preposterous, but consider this. Despite what the revisionist historians tell you, there is no mention of the "moon" anywhere in literature or historical documents -- anywhere -- before 1950. That is when it was initially launched. When President Josef Kennedy, at the State of the Union address, proclaimed "We choose to go to the moon", he may as well have said "We choose to go to the weather balloon." The subsequent faking of a "moon" landing on national TV was the first step in a long history of the erosion of our constitutional rights by leftists in this country. No longer can we hide from our government when the sun goes down.
Archimedes also had trained sharks with friggin mirrors on their heads.
*DrugCheese rants*
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.
Sorry, but saying that one failed experiment proves no one could do it isn't science, it's just sour grapes. All it proves is that it didn't work that time. Who knows, a few more mirrors, a little faster aiming, it coulda been a contender.
One change I'd like to see, the mirrors in Archimedes day were generally polished brass plates. He probably would have used polished brass shields Say, 2 1/2 feet diameter (a little less than a meter). Each would have been 'aimed' by the man holding it. They'd be a little convex which would blur the focus. The target would probably be the furled sails on the galley. The wood on the sides would be wet, harder to start. Decking or sails now, dry and easily flammable. So, varying from this test, some parts are easier and some parts are harder. For limits on this approach, there used to be a unit in France that could run a small blast furnace. Took hundreds of mirrors, but there is no practical limit. 20 years ago, the Department of Energy wanted to build a big power plant using this system. It scales nicely.
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.
Christ, you and lkeagle are powerfully confused about what's being claimed. The center of the sun is your point source of light because of symmetry. It's incredibly far away. Now draw lines from it all the way to the edges of your wee little mirror. These lines are nearly parallel. Why? The _mirror's_ arc from _the_sun_ is almost imperceptibly small. Not the sun's arc from the Earth.
We could be orbiting a giant-ass sun that occupies half the sky but whose center is still the same distance away as the current sun's - its _radial_ lines would still emanate from the same _center_ as before. Its apparent size in the sky is ****ing irrelevant.
Hasn't every CS major tried his hand at ray casting? I guess not.
Anyway, the completion of this saga: Your nearly parallel lines have reached the edges of this 1 square foot mirror all the way from the sun. Assuming the rays hit a face-up mirror (best case), they travel 0.00000001% further to reach the 100ft mark you've set. How much more do they widen?
original 1ft of separation + 1ft * 100ft / distance from sun ft.
try drawing the triangles.
my guess: this works out to a lot less than 3 ft. now diffusion? lkeagle might be talking about the edges of the mirror or the dust in the air or something very very subtle and smart. or he has no idea how to grasp the actual point that was made. please beat him accordingly.
The problem with that is that you need both sides of the mirror to be _perfectly_ parallel, or you'll aim slightly at the wrong angle. Give it a bit of variance, as in, not all mirrors are identically imperfect, and you have each soldier aiming at the completely different spot.
To put things in perspective, as late as the renaissance making something even reasonably flat was a major challenge. E.g., since we're talking mirrors, the room padded with mirrors (of a reasonable quality to not distort the king's image) at Louvre is one thing most people don't fully understand. It looks like "meh, so they just put a bunch of mirrors on the walls. Big deal." For that age, it was more expensive than plating those walls with solid gold plates.
Expecting some ancient greek smiths to hammer perfectly flat mirrors with perfectly parallel faces, is really a laughable concept.
A polar bear is a cartesian bear after a coordinate transform.
"That's why it's always worth having a few philosophers around the place. One minute it's all Is Truth Beauty and Is Beauty Truth, and Does A Falling Tree in the Forest Make A Sound if There's No one There to Hear It, and then just when you think they're going to start dribbling one of 'em says, Incidentally, putting a thirty-foot parabolic reflector on a high place to shoot the rays of the sun at an enemy's ships would be a very interesting demonstration of optical principles."
Just because we haven't been successful in reproducing the machine, doesn't mean it was a myth. It just means that it was poorly documented, or too heavily copyrighted with DRM for the original documentation to have been released into the public domain for us to dissiminate, or that we just don't know how to reproduce the exact circumstances that led to the event.
Thanks,
Leabre
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.
Lasers Controlled Games!
math for gunnk since he thinks the distance doesn't matter at all. Or math.
Lasers Controlled Games!
-Eric
SJW: Someone who has run out of real oppression, and has to fake it.
Hehehe. Flaming idiots, so to speak? I do have to agree that at 150 yards a volley of flaming arrows certainly does seem more reliable and practical.
No, they are not engineers by any means. Yeah, they build simple equipment for their experiments, but they're not engineers. They rarely focus on building systems that must work for years on end, for instance. They build, but they do not truly engineer.
Indeed, I see you have resorted to ad hominem attacks. I take that as an indication of my victory in this discussion.
Cyric Zndovzny at your service.
hint: aim at the sails/rigging. they were low mass & highly flamable.. their burning would have also rendered the ship's immobile (as well as frightening the sailors into jumping ship).
Unfortunately, the AP article disseminated around the world is short and loose on the facts of what happened in SF, thereby leading to a lot of undeserved blame for the outcome of the experiment on the MIT participants. Read about what really happened, in an account that the MythBusters agree is factual, in the test diary.
Things to note:
The MIT team's goal, as stated in the original essay, was to test the technical feasibility of a solar ray for igniting wood at approximately 100ft with a simple, inexpensive setup. The conclusion from this test is that it was inconclusive because of the unknown effects of different experimental parameters (what if the target was a real Roman ship, or at least more seaworthy? what if the bronze mirrors had all been of uniform quality? etc). Sure, given much more resources and time, a much larger scale test could be done, but calculations had indicated that the array would be sufficient for achieving the same result as the initial MIT test, and the costs of doing the experiment were already beyond what was anticipated. However, assumptions about the target that would be used were not correct, and probably significantly affected the result of the experiment.
All-in-all, my understanding is that the MythBusters-MIT collaboration was a fun one although the results were not decisive enough to change anyone's opinion about the technical feasibility of the myth. Everyone is entitled to their own opinion. The experiment should be viewed as a fun educational exercise, NOT hard-core scientific research. The press that was achieved from the initial class exercise was unanticipated. That is, there was NO effort made to promote the class exercise. Instead, news of it spread by word-of-mouth, on blogs, and eventually into the mainstream media. People shouldn't take everything they read about in the news seriously, and should read what was posted about the attempts to get the facts about what the real purpose was behind the experiment (that is, to conduct a fun exercise for a class, NOT to claim that it had never been done before since links to past accounts had been provided to the students, and NOT to claim that the exercise was cutting-edge research).
Disclaimer: I am not speaking for the MIT team that conducted this experiment and was not a member of that team.
Come on gunnk! Have you looked it over? Do you still think it doesn't matter? Have you checked my math?
Lasers Controlled Games!
I challenge you to respond! :) C'mon, I want to know why I am wrong! Or at least an admission that you are. One of us definitely is.
Lasers Controlled Games!
The morning after my post I realized that the sun does not simplify to a point source because if it did it would be visible as a point. Sorry it took me so long to acknowledge this, but the reason I had time to think about my Slashdot post in the first place was because Hurricane Wilma had just taken electricity away for the week.
.436 feet on the mirror. This means that a square of (.128 feet)^2 would still catch all of the rays sent by the sun directly through the mirror! It would require exceeding 229 feet before no point would receive full exposure from a square foot mirror.
.1 feet long will receive at least 92.5% of the sun's exposure.
Using your numbers:
100 feet away, the sun would occupy a disc of radius
The rigorous way to go about determining effective intensity would be to integrate over the area of the target, taking into account clipping of the sun's image through the mirror - which won't necessarily block a substantial portion of the sun's disc. Even at 229 feet, a square with sides
And I suspect that the edges of the sun don't shine on us with nearly the same intensity as the center does, but my eyes don't have the dynamic range for that. The less the relative strength of the edges, the more the sun resembles a point source and the more the results would approach my original over-simplification.
But that would be just a lucky coincidence. Sorry for my unjustified caustic tone and thanks for helping me see straight.