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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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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.
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I like mythbusters, but they missed the boat, so to speak, on this one.
I build a Death Ray and it works great.
-Peter
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
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.
Killfile(TGK)
No trees were killed in the creation of this post. However, many electrons were inconvenienced.
Read your link. Greek fire was invented in 673 AD.
I learned in boyscouts a very simple way to aim the reflection of the sun from a mirror at a distant object. You need a mirror that is reflective on both sides with a hole in it. Look through the hole at the target. There should be a spot of sunlight on the ground or your body from the sun shining through the hole in the mirror. Angle the mirror such that the reflection in the back of the mirror of this spot of light lines up with hole in the mirror. The suns rays will now be directed at the target. Many outdoor provisions companies sell small mirrors of this type for signalling purposes in emergencies.
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.