Correct me if I'm wrong, but the ability to tell the time with the least equipment and fuss has to be the ultimate goal, doesn't it?

Standing outside and facing north you at least know if it is morning, noon or afternoon. Or night.

But have you ever looked at your nose? As a gnomon, I mean. It is a gnomon, isn't it! So all you have to do is face south (and the slope of your nose is therefor pointing north) and, carefully make marks around your top lip every hour.

Add a compass, or a piece of some migrating birds skull - or check for moss (north side of trees) or a loose boy scout - and you're made.

And possibly this is why the nose has evolved. Chimps evolved without noses. Perhaps I should look at different races and how their noses may show their latitude. Any mileage in this?