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14.03.2016 admin
As they head into the shadows, not quite knowing where the tunnel will lead, the sudden darkness and the drop in temperature startle their senses.
A giant metal wheel sits in the middle of the platform, and the visitors each grasp a handle that juts out from its smooth edges. It sounds like science fiction, but this is the real vision for the 10 000-Year Clock, a monument-size mechanical clock designed to measure time for 10 millennia.
This clock, the flagship project of Hillis's Long Now Foundation, is a wonder of mechanical engineering. For an engineer who had built his career on making fast machines, Hillis found this story of forethought striking.
He took his idea to a private mailing list that included future-minded thinkers such as Stewart Brand, founder of the WELL (the Whole Earth 'Lectronic Link) online community, and electronic musician Brian Eno.
Bezos, who got his undergraduate degree in electrical engineering and computer science from Princeton, was also drawn to the project by the sheer geeky quality of the thing. For inspiration, the team looked backward—to enduring ancient monuments like the Egyptian pyramids and Stonehenge.
Even after the intrepid explorers of the future reach the site, the drama of their journey would continue to unfold as they enter the mountain, snake through tunnels, and climb up the spiral steps past the clock gears. Although much of the clockwork is similar to the workings of a standard grandfather clock, it differs from an ordinary analog gear-driven clock in a few key ways. The clock is being designed modularly, so visitors will be able to see how the various parts go together. Even seemingly simple questions proved difficult to answer, such as: What should the clock be made of? For the clock's components, the team has been selecting durable materials such as stainless steel, titanium, and ceramic, whose longevity can be gauged through high-temperature testing. There was a concern, however, that over the centuries the clock's components might weld together if everything were made from the same material. To maintain the clock's accuracy, Hillis and Rose had to figure out a way to somehow sync their clock, buried deep within a mountain, with the outside world.
The problem with memory wire, as with the use of electronics, was the lack of transparency. To recalibrate the clock, the current plan is to use a titanium box that pops out one normally concave side when the air inside heats and expands at around solar noon. Ultimately, though, a patch of land owned by Bezos outside Van Horn, Texas, was chosen for the first clock installation.
For all the creative deliberation, hard work, and long-term planning, there's one thought that continues to haunt these engineers. Two hikers cut through a stretch of cactus-filled desert outside what was once the small town of Van Horn, near the Mexican border, in West Texas. For the next several hours, they push and walk and push and walk in a circle, methodically, silently, until the wheel will turn no further.
Danny Hillis, an electrical engineer with three degrees from MIT who pioneered parallel supercomputers at Thinking Machines Corp., worked for Walt Disney Imagineering, and then cofounded the consultancy Applied Minds, dreamed up the project in 1995 to get people thinking more about the distant future. Over the course of its 10 000-year life span, it will be able to power itself enough to keep time, synchronize that timekeeping with the sun, and randomly generate unique melodies on its chimes so that visitors will never hear the same tune twice.
Meanwhile, a construction crew in Texas has been blasting and digging through limestone to create the tunnel.
A clock that's meant to last for 10 000 years poses a fundamental challenge for a speed-obsessed age: How do you engineer something for the very distant future and get people to care about it today?

Over the lifetime of the clock, the chime generator will ring a series of 10 bells in a different arrangement each time. Hillis says he chose that time span because that's about how long human technology has been around.
Living in an increasingly accelerated culture, he thought, was eroding our ability to think concretely about the future.
The idea captivated the group, and Hillis began to consider more seriously how his clock might actually get built. Society needs to think long term or risk failing to appreciate such century-spanning problems as climate change and deforestation, Rose told me. Finally, they would arrive at the chosen spot, where they would wind the chime generator and hear the bells ring. Given the vagaries of human history, it's reasonable to expect that people might one day forget the clock even exists.
Working in modules has the added advantage of letting the engineers tweak different elements of the design without having to start from scratch each time. The team needed materials that could stand up to thousands of years of wear and tear, yet few studies could shed light on the matter. The gears are made of type 316L stainless steel, a marine-grade alloy that is extremely resistant to corrosion.
So most of the pinion gears, as well as the pendulum and encasement, will be made of titanium. The closest real-life parallel is the bearings in satellites, says Rose, and those have only a 20-year operational life. The clock will be housed in a tall vertical chamber at the tunnel's end [model shown here]. This will trigger a correction in the pendulum if it's swinging too quickly or too slowly. They needed a cliff that was fracture free, so they could dig the tunnel, and also south facing, for solar-power generation.
After walking for the better part of a day under a relentless sun, they struggle up a craggy limestone ridge. In Washington state, engineers at Seattle Solstice are refining a giant stonecutting robot that will eventually be shipped to Texas and deployed inside the mountain, to etch the spiral staircase directly into the rock. The basic notion may have been a quick sell, but actually building the clock, he and Hillis knew, would be immensely difficult. They realized that what each of these very different entities has in common is that the visitor experiences it as a rite of passage.
That meant building the clock in a faraway, hard-to-reach place, somewhere requiring a real commitment to visit. So for the sake of the wayward traveler who just happens upon the clock by accident, the operation had to be obvious just from looking at it. And instead of having a pendulum that counts off each second, the clock's pendulum has a base of 10 seconds.
They are also discussing the possibility of including some kind of instruction manual, likely in the form of photographs or diagrams. He had just returned from the Svalbard Global Seed Vault, in Norway, where millions of seeds from around the world are now being stored in a remote, highly protected underground bunker as a hedge against climate change and human conflict. For insights, they looked at the 11 000-year-old tower of Jericho, believed to be the oldest existing building in the world.

The difference in temperature, amounting to tens of degrees, causes air to move from the hot tank to the cool one during the day; when the surface tank cools down at night, the airflow reverses. How long you spend winding the clock will depend on how long it has been since the last person visited: Winding it fully will take three people about 8 hours. The team knew they wanted somewhere remote, to enhance the experience and because cities are so vulnerable to the ravages of war.
With 150 meters of tunnels and shafts to excavate, the construction crew is using high-precision blasting and robotic mining equipment. Finally they come to an opening in the rock, the mouth of what appears to be a long, deep tunnel. At noon the next day, they're suddenly awakened by the ethereal tones of chiming bells. According to the myth, back in 1386, the builder of the University of Oxford's New College planted some oak trees [PDF]. Building an ageless clock, Hillis suggested, was a way to bring really long-term thinking back.
As Hillis wrote in his essay, "My engineering friends worry about the power source: solar, water, nuclear, geothermal, diffusion, or tidal?
Given the highly skilled staff, the high-tech construction and machining equipment, and the rarefied raw materials involved, that seems about right. So it will tick at one-tenth the speed of a regular clock, which should help its gears, bearings, and other components last at least 10 times as long. They haven't yet decided, though, where to put the instructions or even how to alert people 10 000 years from now that the clock exists. Rose also considered the design of nuclear-waste storage facilities, which are built to last for centuries or longer. Of course, that's assuming people 10 000 years from now will still be able to perform manual labor.
They also figured it needed to be underground to have a shot at lasting for millennia, but not so far down that it would be below the water table. In 1999, the Long Now Foundation purchased some land in eastern Nevada as a possible home for the clock. Eventually, the clock's components will be shipped to Texas and reassembled inside the mountain. A black globe suspended above depicts the night sky, encircled by metal disks that indicate the year and the century. The purpose was to have wood that could be used to replace the oak beams of the college's great dining hall hundreds of years in the future. And rather than having a 12-hour face, the clock will display the positions of the stars on a black globe, surrounded by dials showing the year, the positions of the sun and moon, and other astronomical data. The weights will then have enough potential energy to keep the 136-kilogram pendulum swinging for the next day. Although the project was originally slated to finish in 2001, these days there is no official schedule for completion, and the team estimates at least a few more years of construction lie ahead before the clock will be completed and opened to the public.
Granite is difficult to cut, so they settled on limestone—soft, but not so soft as to easily fall apart.

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