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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."
For the unitiated, 2.009 at MIT is a class in course 2 (mechanical engineering), called Product Engineering Processes.
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And Mythbusters is LAW!
The Tech Terminal
That's an Archimedes Death Ray, now banned from all commercial airline flights. Lame.
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.
Not exactly the same concept, but the Solar Death Ray always reminded me of this.
How's my typing? Call 1-800-eta-shut
I like mythbusters, but they missed the boat, so to speak, on this one.
I build a Death Ray and it works great.
-Peter
as tin foil hadn't been invented yet, his enemies would have had no viable defense against this weapon. Devastating!
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?"
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
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.
...just my 2 gil.
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.
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.
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.
"A language that doesn't affect the way you think about programming, is not worth knowing" - Alan Perlis
A mirror can also prevent the server from burning up.
Marvin knew: "Think of a number, any number..."
They run these unscientific experiments (most involving explosions or decaying corpses) and then "conclusively bust" myths. Some experiments are fun and interesting, but most don't deserve the hard conclusions they assign.
It's really annoying when people take accept their "proofs" as proofs.
I'm confused, I thought adding a lot of mirrors stopped things from catching fire around here.
Since the Greeks had gears and ropes, it would have been possible to build a mechanism whereby one person could rotate many mirrors. I'm not saying it would have been easy, or even that it was done this way, only that they had all of the required technology to do it.
A second possibility would have been similar to the sighting mechanism used very successfully by the Dambusters in their attacks in World War II on German dams. They needed to know when they were at a certain height above the water, level, and at a certain distance from the dams. They achieved this by angling the searchlights to cross over at the right height and strike the dam at the right distance. To know if they were level, they used pieces of wood at different distances, which would line up when the aircraft was level.
To line the mirrors up with the ship, you'd need to know when the light from the sun would strike the ship at the right height. Angle of incidence equals angle of reflection, so as the sun moves through the sky, you'd need to shift the mirrors both horizontally and vertically to keep the light on the right spot.
If you had a hole in the mirror and stood behind it, you could swivel the mirror to face the ship. Since the ship would be at water level and the mirror would probably have been much higher, the mirror would have to have pointed at the tallest mast. It would be the only thing visible. To ensure all mirrors pointed the right way, each mirror would need behind it a stick that needed to line up with the mast, but set at an angle such that each mirror would line up differently along a crude parabolic curve. Shouldn't have been hard, with the Greek knowledge of geometry, which they were exceptionally good at.
If the action was brief enough and at the right time of day and at a predictable distance, the vertical angle would be unimportant. If it had to be ready for ANY time of day OR at ANY distance, then you'd need to have the poles on which the mirrors were attached themselves movable.
If you mounted the pole on one end of a see-saw, then added weights to the other end, you would be able to adjust the vertical angle of the mirror to whatever was required. The line of the see-saw would be parallel to the normal of the mirror. You can tilt the mirror such that the reflected light will intersect the ship at the same point that the line along the see-saw intersects the ship. This would guarantee all mirrors get identical vertical alignment.
We now have a guaranteed way of aligning a great many mirrors onto an identical point on a ship at any distance at any time of day, using nothing more than geometry, alignments and pivots. Again, this is NOT to say that this is how it was done - we don't know HOW it was done, or even IF it was done. What this is saying is that the arguments against have largely been based on sophistication, but that the required level of sophistication was certainly achievable had anyone wanted to achieve it.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Read your link. Greek fire was invented in 673 AD.
I can only assume you were misinformed or made the wrong assumption about the show. Perhaps you are missing out on what Mythbusters is about. It's this funny little thing called "entertainment".
It is not an "Educational" program. It's about 2 guys who used to do FX work for Hollywood using their skills with "getting close" to the right thing trying to see if they can replicate urban legends.
The funny thing is, you probably missed the episodes where they revisit old myths they worked on. If the show receives enough requests from the audience or they decide they didn't do something justice, they give it another go. They did the "chicken gun" myth a couple times because they kept doubting their setup. I didn't get to catch the final conclusion, but I would say that by the time they were done, they had tried everything available to them to see what would happen.
Other examples of where they've done things incredibly right include hanging a pig carcass from a hook on a pivot and shooting it with various guns to prove that no, taking a gunshot does not make you fly back and do cartwheels, and using a ballistics gel dummy (with a pig backbone to simulate the human one) to determine if you could be injured by a ceiling fan (even the high-powered ones didn't do much until they sharpened the blades).
Yes, most people who have shot guns would understand that Hollywood fakes it, but for the average Joe who just watches movies and TV, with no physics background, it was probably something neat to see.
Yes, they blow stuff up. They put a crash test dummy through hell. Yes, they keep fuck-ups on the film, because that makes the show more approachable to the target audience- it isn't a dry, we-just-provide-the-facts-ma'am-only-the-facts show. It is supposed to feel like you and you buddies could be right there with them. You know what, though? It's entertaining. And for a channel that brings us 5 variations on "hey, we're going to destroy a room in your house by letting a half-assed decorator come in and ruin your happiness", it's a damn good show.
Many of their conclusions are valid. They've shown that pissing on the "live" rail of a 3-rail train system will not shock you (urine stream is too fragmented by the time it hits the rail for electricity to travel), exactly how many bug bombs you would have to set off in a room with an ignition source before the gas was concentrated enough to explode, and that you cannot get sucked into the intake on one of those firefighting helicopters while wearing scuba gear, only to be dumped into the fire and die.