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MIT Students Show How the Inca Leapt Canyons
PCOL writes "When Conquistadors came to Peru from Spain in 1532, they were astonished to see Inca suspension bridges achieve clear spans of at least 150 feet at a time when the longest Roman bridge in Spain had a maximum span of 95 feet. The bridges swayed under the weight of traffic terrifying the Spanish and their horses, even though, as one Spaniard observed, they were almost as "sturdy as the street of Seville." To build the bridges, thick cables were pulled across a river with small ropes and attached to stone abutments on each side. Three of the big cables served as the floor of the bridge, two others served as handrails and pieces of wood were tied to the cable floor before the floor was strewn with branches to give firm footing for beasts of burden. Earlier this year students at MIT built a 70-foot fiber bridge in the style of the Incan Empire. The project used sisal twine from the Yucatan Peninsula and anchored it by wrapping it around massive concrete blocks. The weekend's burst of activity was preceded by 360 hours of rope-twisting as the 50 miles of sisal twine was turned into rope. Working together as a group was part of the exercise. "A third of the time was spent learning to work together," one of the students said. "But after a while, we were banging those cables out.""
Haha, talk about a late story at a completely random time. I was one of the leaders on the project, lots of late nights twisting twine together. If anyone has any questions feel free to ask.
You gotta find first gear in your giant robot car
People here seem to be missing the point - it isn't that this stuff isn't trivial compared to todays engineering, it is. But it's more revealing about the fact that non-western civilizations had an advanced grasp of the physics/science behind this stuff. They knew how to take advantage of rope tension. A bridge like this isn't so impressive today. It's easy to build. But to come up with the design is the hard part.
Don't even bother replying to those cretins. Slashdot needs a semantic analyzer to weed out the obvious gibberish.
The higher the technology, the sharper that two-edged sword.
"Here, Icxtuatl, hold this."
... aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaah!" {fwap!}
"Ok. Say, looks like you're building a bridge or som
The higher the technology, the sharper that two-edged sword.
Not on purpose as far as I remember, but when the rope reached a certain size it couldn't just be reeled up by hand anymore and we had to have two people act as a reel, twisting the rope around themselves as they walked down the hall. Eventually they'd be tied right up against each other with something like 70lb of rope around them.
You gotta find first gear in your giant robot car
Mmm... kinky. :)
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
According to Mayan glyphs found carved in stones near one of the bridges, Bolontiku, Ixzaluoh and Ac Yanto were in fact idiots. Ixzaluoh in particular, was believed to have had difficulty finding his ass, despite using both hands.
"I've got more toys than Teruhisa Kitahara."
The Aztecs were in and around the region of Mexico, the Incas were in South America roughly where Peru is today. The ones who had died out were the Maya, although there were several small tribes in Central America (Chorotega, Guatuso, etc) between the two mighty empires.
Seven puppies were harmed during the making of this post.
I was walking around campus one day and saw the cement pillars going up. They were BIG concrete boxes, about 4 stacked up taller than me and about 2-3 feet on a side. I'm not sure what happened to that concrete but it seemed wasteful to make _just_ rectangular prisms. No offense, especially since I'm a 'utility-focused' engineer, myself, but I did think-- wow, these are harsh. It might have been fun to paint, or sculpt them (before being set, or with plaster afterwards), with Incan designs or information about the construction process.
The rope bridge itself looked fun to walk on, but it had a sign saying no trespass. That sign was up the whole time the bridge was there, though it is possible people might have walked around the bridge for fun and jumped around to see how it swayed and bubbled. At that point the bridge might have been up a while and losing tension and so the sides of the shallow creek interfered with the hanging bridge aspect.
It's great to see thought provoking structures go up around campus. Rock on.
The descendants of the original bridge builders still do this each year at one of the original sites, using techniques handed down by previous generations. Photos here:
http://en.wikipedia.org/wiki/Inca_rope_bridge#Renewing_the_last_bridge
In the light of that, I have three questions:
Are you doing it again?
Do you need volunteers?
Are the rest of the volunteers likely to be hot, naked chicks?
I have to admit that if the answer to the third one is "no" I may not be very interested.
Chernobyl 'not a wildlife haven' - BBC News
Sadly for him, the the Mayans had not invented the flashlight or the map.
What sound do people on rollercoasters make? Hint: it's not Xbox 360.
Maybe describing it in a context that any Slashdotter would understand might help.
Aztecs:
I, for one, welcome our Mesoamerican, Cortez-hating, Virgin of Guadalupe-worshiping, human-sacrificing, maize-and-bean-growing, empire-building Mexica overlords.
Incas:
I, for one, welcome our pre-Columbian, sun-loving-with-bare-titicas, Conquistador-fighting, Machu-Picchu coca leaf-chewing, Andean-whistling and bridge-building overlords.
Back in 1997 NOVA did an episode, "Secrets of Lost Empires: Inca", where they went to Peru and filmed the natives building a grass suspension bridge in the traditional style. I'd recommend watching it if you want to see one of these things under construction, it really it amazing how they go from dry grass to a sturdy rope bridge.
Yep, hence the country 'Argentina'.
These aren't suspension bridges, as the comparison to the George Washington bridge in the article clearly shows. They are rope bridges.
The difference is that the walking surface is not suspended from the overhead cables. It is instead supported by tension in the ropes that compose it.
The critical difference from the MIT bridge and the monkey bridges many of us made in the scouts is that it was supported by concrete blocks instead of lashed wooden A-frames and stakes. And that the MIT students put a rather impressive number of hours into making and thoroughly vetting their own rope and design.
Can you be Even More Awesome?!
So the moral of the lesson is that ancient men weren't idiots.
"We tend to scoff at the beliefs of the ancients. But we can't scoff at them personally, to their faces, and this is what annoys me." - Jack Handey
-kgj
-kgj
The Maya hadn't died out. Quite the contrary, there were (and are) huge populations of Mayan people in Yucatan and Guatemala. They just weren't the dominant civilization at the time the Spanish arrived. There were probably about a million "Mayans" (exact numbers being impossible to come by for many reasons) while Central Mexico may have had as many as 25 million people (most estimates put it in the 10-15 million range).
No kidding. I've seen rope bridges before. I made like a finity of those at Scout Camp.
I cried real tears when Li Mu Bai died.
This happened years ago at IIT Madras, India http://www.civil.iitm.ac.in/events/paper-bridge.html
Trajan's bridge over the Danube (built between 103 and 105) was over a thousand meters long and 15 meters wides. Each individual arch that made up the bridge was over 35 meters long. Roman bridges in Spain that still exist extend over 800 meters. And then there are the various Byzantine bridges ...
Not to mention the two mile long pontoon bridge built by the Persians so that their foot soldiers and cavalry could cross the Hellespont prior to the battle of Thermompylae.
Sure, a 150 foot rope bridge is a neat design, but it doesn't really compare in scale of engineering to the bridges of the ancient world.
...but, can you get wireless internet in the middle of it?
Sleep your way to a whiter smile...date a dentist!