You hit a hard return within the quote marks surrounding the url - like so...
I've always been partial to the Song clock, which was built during the Song Dynasty (around 1070) but was dismantled either by or just ahead of invading Jurchens. By the time it was safe to put back together, no one was sure exactly how to do it.
It was also assembled in an odd city in China - about 500 or 600 years after the clock was built, a Dominican missionary turned up, started trying to explain to people about the 10 commandments and found they already knew 'em. There'd been a Jewish community there for hundreds of years. No one is sure how they got there.
Anyway, the clock is pretty awesome - the oldest known chain drive (like a cuckoo clock or a bicycle), built with an armillary sphere (like a planetarium) on the top level... here's one description:
The clock tower consisted of three levels. The upper level contained an armillary sphere. This represented "the great circles of the heavens" which allowed astrologers to make accurate astronomical observations. On the middle level, there was a celestial globe which displayed the movements of celestial bodies, and the bottom level had wooden mannequins which struck the time of day. The whole tower formed a single mechanism which was turned by water power, without any human effort. The clock's precision was comparable to a sundial (Bulliet 333). The sphere was comprised of 12 rings in three layers, each of the rings being marked with a scale. From the sphere one could directly read off the positions of the 24 Solar Terms, and could find a star or planet by looking through a sighting tube.
The Taiwanese government managed to recreate Su Song's clock tower on a smaller scale in the 1990s.