A Brief History Of (Keeping) Time
13:30
A History of Time - Seconds, Minutes, Hours, Days & Weeks
5:47
Who decides how long a second is? - John Kitching
17:18
Some People Won't Be Able to Listen to This Video
8:31
The Underground Clocks of Paris
6:26
Are We All Related?
15:11
Why Do Clocks Run Clockwise? | Neil deGrasse Tyson Explains...
5:14
Como Un Iglú Te Mantiene Caliente
12:30