Archimedes Death Ray

Werner Heuser writes "Ancient Greek and Roman historians recorded that during the siege of Syracuse in 212 BC, Archimedes (a notably smart person) constructed a burning glass to set the Roman warships, anchored within bow and arrow range, afire. The story has been much debated and oft dismissed as myth ... Intrigued by the idea and an intuitive belief that it could work, MIT's 2.009ers decided to apply the early product development 'sketch or soft modeling' process to the problem."

MIT numbering...

[by Anonymous Coward]

For the unitiated, 2.009 at MIT is a class in course 2 (mechanical engineering), called Product Engineering Processes.

Obligatory Coral link

[bcat24 (914105)]

The server seems really slow right now, try this [nyud.net].

Re:Obligatory Coral link

[cluckshot (658931)]

I don't suppose that reminding the crowd that Archamedes had quite a history building some pretty massive things and doing so using some pretty cute tricks with some really high math is in order. I am quite sure that Archamedes was aware of the solar reflection and other issues. It is my understanding that he used bronze mirrors of very large size that were essentially slightly parabolic with a focal range about 1 mile. I do know he possessed the math, and architectural skills to do this. This is typical of ratio projection used in buildings.

I do know the results in history of this man's work are pretty well established. He pretty much set about and did whatever he intended to do. As a scientist he was neither politically correct nor foolish. He was the best of his time and frankly would have been pretty good today.

The Mythbusters assumed that some things were too big to do. This would not have been a problem for a man who engineered the roofing of big Greek buildings.

Re:Obligatory Coral link

[modecx (130548)]

Not only do they make the assumption that their resources are better, which in all honesty is fair in almost all cases, but (in this instance) they make the grave assumption that they're smarter than Archimedes, or even normal, average people for that matter--and that's where they go wrong. I've lost count of the things they screw up that should be evident to many high school physics students. They're entertaining, and It's always fun to watch them blow stuff up, and that's their purpose, after all.

That's not a magnifying glass.

[by Anonymous Coward]

That's an Archimedes Death Ray, now banned from all commercial airline flights. Lame.

Earlier experiment like this

[Steve1952 (651150)]

This sort of demonstration has been done before. I remember reading an article in Time magazine in the 1960's or 70's that reported on one such earlier experiment. Many men held polished flat "shields" in the sun at the right angle, and confirmed that they could cause charring in a simulated boat target.

Solar Death Ray

[bobgoatcheese (455695)]

Not exactly the same concept, but the Solar Death Ray [solardeathray.com] always reminded me of this.

No tin foil

[complexmath (449417)]

as tin foil hadn't been invented yet, his enemies would have had no viable defense against this weapon. Devastating!

He was duped

[complexmath (449417)]

in 212 BC, Archimedes (a notably smart person) constructed a burning glass to set the Roman warships, anchored within bow and arrow range, afire.

If the enemy ships were anchored within bow and arrow range, I suspect that while Archimedes was fiddling with his mirrors, a few archers dipped their arrows in pitch and fired them at the fleet. Eventually, when Archimedes finished aiming his master weapon he was overjoyed to discover the fleet in flames. Archimedes reported his success to the king, and went down in history as the oldest recorded example of a horribly over-engineered solution to a simple problem.

Re:He was duped

[TGK (262438)]

It's worth pointing out that the availability of really useful materials for incendiary warfare was notably lacking in the ancient world at this time. Even the Romans, with their much more sophisticated war machine never managed to deploy fire based weapons of any magnitude.

Dr Lendon of the University of Virginia and a leading expert on combat in the ancient world is oft quoted in reference to the opening scenes of Gladiator as saying this:

"The opening battle is remarkably accurate for a Hollywood depiction of Roman warfare... if you think away the Napalm. The Romans didn't have anything more flammable than olive oil"

Flaming arrows, while they make good cinematography, weren't in the Greek arsenal at the time.

Re:MythBuster

[Shook18 (878947)]

And Mythbusters is LAW!

Re:MythBuster

[writermike (57327)]

For what it's worth, the MIT folks said they couldn't unequivocally rule it out. They didn't say it happened. One of the main points on Mythbusters was that it seemed like it might work, but the fleet would have had to remain essentially motionless for the wood to get hot enough for ignition. The MIT folks did nothing to answer that as they the mirrors and the "ship" were motionless until ignition.

You don't have to burn wood -- people will do.

[kale77in (703316)]

Igniting sails, or burning/blinding people is much easier than setting fire to wood (especially a hull that could be wet). I've always thought that the victory was due to the psychological effects of the weapon on morale more than the outright destruction of vessels.

Re:Mythbusters

[pete-classic (75983)]

I like mythbusters, but they missed the boat, so to speak, on this one.

I build a Death Ray [hutnick.com] and it works great.

-Peter

Re:Mythbusters

[by Anonymous Coward]

If you check out the application [discovery.com] to develop a better death ray experiment, you see that one of the criteria for participation is:

You must not be a candidate for elected public office, and if selected as a participant, you will not become a candidate for elected public office until 12 months after the initial broadcast of the last episode of the series in which you appear.

I'm wondering if their logic is "If you can build a death ray, you can't run for office, since it would give you an unfair advantage. Who the hell is going to vote against the guy with the death ray?"

Re:Mythbusters

[skiflyer (716312)]

In case you're serious, it's because of airtime laws and public elections. If they put this person on TV and their a political candidate, then they must also allow equal airtime to their opponents.

I like your idea better though.

Re:Mythbusters

[LnxAddct (679316)]

Not to argue that the mythbusters are always wrong, but they were wrong this time. Not only does the number of mirrors count, but they must be lined along a parabolic path, must be "perfectly" flat (in this case) and as the article stated, the point of focus changes at 36 feet per hour so you have to keep the mirrors "up to date". There are a lot of factors to take into account, and optical physics to solve. You can clearly see MIT's results, setting the ship on fire, and it was made out of wood stronger than what would have been used by the Romans. The ship hit over 1100 degrees and burnt pretty well. Moral of the story: Myth Buster's results no longer matter because a contradiction to them was proven to exist.
Regards,
Steve

Re:Mythbusters

[Wavicle (181176)]

Okay, if we're going to use this argument...

In the MIT experiment, the boat was arguably a very poor replica of a trireme. It was painted black to optimize the energy transfer (which in the end didn't matter). The target was not moving, only the sun. The target was not in water. Highly polished silver on a superflat surface would have been the closest thing that the ancient greeks could have had to simulate those mirrors, and if such a thing were possible, it would have been enormously expensive. The greeks would have had people holding the mirrors, not tables and stands.

At 100 feet, your each soldier's heartbeat would have defocused the weapon, even if he could otherwise hold perfectly still (which he couldn't). To protect the soldiers from archers, Archimedes' weapon would have to hold focus at a much greater distance.

All these things the MythBusters got much close to right and the MIT folks avoided.

Nobody is arguing that focusing the sun on something won't result in transfer of lots and lots of energy. That would be just silly (the web page says they wanted to see if it was at least possible - damn, they had to go to MIT to figure out a finite amount of energy will cause wood to burn?!). The question is could such a thing have been constructed and put into use by the Greeks. And that's something the MIT folks answered far less effectively.

Re:Mythbusters

[Wavicle (181176)]

The size of the focused target is way too big for light wave interference to have an effect. Parabolic mirrors are useful because if we take the sun to be a point source (which it isn't, but it's close enough) then all the rays from the sun will converge towards the mirrors focal point. It's the same principle as burning ants with a magnifying glass - if you put a 3 inch diameter patch of sun into a 1/4 inch diameter circle, you'll have a very, very intense spot of sunlight. Here we're using a mirror to focus the sun.

Re:Mythbusters

[Shamashmuddamiq (588220)]

With all due respect, I don't think the Mythbusters are as smart as Archimedes was. You shouldn't impugn someone just because they lived a long time ago.

Re:Mythbusters

[Rob the Bold (788862)]

Don't screw with Archimedes.

Re:Mythbusters

[scdeimos (632778)]

Not to argue that the mythbusters are always right, but they've disproved this in one of thier episodes.

Actually, they only disproved their own design and construction methods on this one. A properly-designed and -constructed working model was demonstrated on BBC Two's practical archeology programme, What The Ancients Did For Us [bbc.co.uk]

Re:Fire good!

[jericho4.0 (565125)]

Doughtfull at best. The Antikythera Mechanism [wikipedia.org] is probably only one of hudereds or thousands of devices that existed at the time, and many people could have been making, buying and useing similar items. Our knowledge of how the ancient Greeks (and others) actually lived is so fragmentary, and we tend to fill in all the blanks with the lowest common denominator answer, ie; we see no evidence of clockwork, therefore they had no clocks. Before the discovery of the Antikythera Mechanism, the suggestion that the Greeks had clockwork would have been met with scorn.

Yes, Archimedes was a very smart cookie, but he was surrounded by other smart cookies, who were also geting up to interesting things. IMO, ancient Greece was pretty much as technologicly advanced as 15th century Europe. Why we ended up having the industrial revolution, and the Greeks did not, becomes a very interesting question.

Re:Glass?

[rpj1288 (698823)]

A mirror can also prevent the server from burning up.

Maybe a combination of the 2

[MoreDruid (584251)]

Maybe he devised a combination of the two. A conical mirror to catch the sunrays and aim them, then a lens to bundle them even more.

I remember a Mythbuster episode where Adam & Jamie try to reproduce this myth/story. They were not able to set a boat hull on fire (they built a replica-piece of boat hull from that age). Stronger still they barely managed to get the temperature higher up... iirc it was only a few degrees higher in the focused center of the beam.