This month’s Discover magazine features a colorful and well-written cover story about the Clock of the Long Now, a clock that’s being masterfully engineered to remain on Earth for 10,000 years (that’s twice as long as the Great Pyramid of Giza) and to keep impeccably precise time along the way. It has yet to be built although an extraordinary prototype is currently on display at the Science Musuem in London. It is a unique clock not only in function and scope but in almost every other way: design, power system, mechanics, placement, and philosophy. Just a small example: it tracks leap centuries. Think about it. In our disposable culture, something that lasts 400 human generations is almost incomprehensible.