Museums almost always advise viewers to not touch the exhibits - and some footage from a US museum shows exactly why those warnings are in place.
Earlier this week, the National Watch & Clock Museum in Columbia, Pennsylvania shared a video of a man and a woman examining one of the exhibits.
Atlas Obscura reports the clock is a 'one-of-a-kind' model designed by artist James Borden.
The man appears to be testing the clock's workings, but after a few moments things go awfully wrong.
In a message on security footage - posted on YouTube - the museum says: "This is why we beg and plead with our visitors to please refrain from touching objects in museums".
However, the comment adds that the couple did notify museum staff immediately after the incident.
Check out the video below, and remember not to try this next time you're out in a museum or gallery:
