[evo]

This gave me a bunch of insight into the workings of those old survival tricks of using analog watch hands to find cardinal directions:

- Since the video starts at solar noon, the sun is always at 12:00 relative to the video.

- Swapping reference frames, if you had a clock face with 24 hours on it, and aligned the "12:00" to point at the equator, the "0:00-12:00" axis would define a longitudinal plane through the Earth, and the hour hand would define a second plane that would intersect with the sun--the hour hand would "follow" the sun.

- Conversely, if you pointed your clock's hour hand at the sun, you would know your "12:00" would be due north/south (depending on hemisphere).

- The same is true for conventional 12-hour watches and clocks, but you must find the "half-way" mark between your hour hand and noon, because the hour hand is moving at twice the speed relative to the hypothetical 24-hour clock.

Neat!

[perilunar]

> Conversely, if you pointed your clock's hour hand at the sun, you would know your "12:00" would be due north/south (depending on hemisphere).

Not quite. In the southern hemisphere the sun moves 'backwards', so you have to flip the clock backwards, or instead point the 12:00 mark at the sun and then the hour hand shows north/south.

[gmiller123456]

Just a word of caution for anyone that would want to use thos in an actual survival situation. If you're really lost, the best thing to do is stay put and wait for someone to find you. If you have to move, knowing which direction is North is pretty useless unless you know enough about where you are and the surounding area. And even then, in such situations, topographical landmarks will likely be more useful.

Not to be a nay sayer, it can be fun to do, and perhaps even useful in some situations. But probably not something that's going to save your life, no matter how many time Bear Grillis used it.