Ahoy, Matey!

I was trying to figure out how far away the horizon is. To make this easier, I decided to make things simple. We'll say that I am on the sea, so that there will be no mountains or valleys. We'll say that I am standing on the deck, which is, let's say, 35 feet above sea level. That makes my eyes 41 feet high. So now how far away am I seeing? My measurements do not help.

So I asked Jeeves if there was an equation to figure it out. He gave me this wonderful tip:
SquareRoot(height above surface / 0.5736) = distance to horizon in miles

Since I am 6'2", the equation equals, oddly enough... Pi. Well, ok. Not really. It does equal 3.14 though. Just don't go any further than the hundredth place.

Now suppose I am still standing on that ship, at 35 feet above sea level. Now the equation equals more than 8 miles! Groovy.