This machine by Arthur Ganson just blew my mind: its engine runs at 200 revolutions per minute but the last gear of its 12-gear mechanism is locked to a block of concrete. It looks still but, in reality, it is moving. You just can't see it because it completes one revolution every two trillion years. How the hell is this possible?

The reason is simple: through the magic of mechanics, each gear runs at 1/50th the speed of the previous gear. A Redditor made the calculations: the engine runs at 200 revolutions per minute moving the first gear at 4 revolutions per minute through the worm gear at the end of its axle (which doesn't count as part of the 12-gear mechanism). The second gear then runs at 4.8 revolutions per hour (which explains why you can barely appreciate any movement). Then things go from glacial to geological to galactic-scale speeds:

Third: 1 rev/10.4 hours

Fourth: 1 rev/3.1 weeks

Fifth: 1 rev/2.98 years

Sixth: 1 rev/149 years

Seventh: 1 rev/7452 years

Eight: 1 rev/372,600 years

Ninth: 1 rev/18.6 million years

Tenth: 1 rev/932 million years

Eleventh: 1 rev/47 billion years

Twelve: 1 rev/2.3 trillion years

That's the reason why the entire machine looks still and the last gear is locked to concrete without any effect on the entire mechanism. In reality, every gear is moving even while we can't see the motion. They just move too slowly—so slow that the last gear isn't affected by the fact that it is attached to concrete. To a human, everything is effectively frozen after the fourth gear.

I know. MAGIC.