Why This Weird Compass Was Such a Big Deal
![](https://i.ytimg.com/vi/WcxKOs7xvRk/mqdefault.jpg)
20:46
Modern Life Depends on This Extinct Rock | Banded Iron Formations
![](https://i.ytimg.com/vi/qK0eCgob81k/mqdefault.jpg)
20:14
We Can't Explain Spiral Galaxies - The Winding Problem
![](https://i.ytimg.com/vi/1ztGpGjO60o/mqdefault.jpg)
13:10
O que há (realmente) dentro de um bueiro?
![](https://i.ytimg.com/vi/NnSWDKfT7FQ/mqdefault.jpg)
15:09
Why This Bicycle Absolutely NEEDS 2 Chains
![](https://i.ytimg.com/vi/mCshn2Rl5cs/mqdefault.jpg)
15:23
How NASA Reinvented the Mechanical Battery
![](https://i.ytimg.com/vi/Dc2zORGbIQM/mqdefault.jpg)
9:27
How to Ship 800 Billion Pounds of Rock (The Marquette Ore Docks)
![](https://i.ytimg.com/vi/XqScUII2z_4/mqdefault.jpg)
20:33
He Learned an Ancient Language Experts Couldn’t Solve
![](https://i.ytimg.com/vi/88bMVbx1dzM/mqdefault.jpg)
21:29