Ok, we all have those moments. You’re moving through the day thinking it’s all going well, and you get a not so subtle blow to the forehead that reminds you that you never know as much as you think you do.
I use the compass on my iPhone regularly on location. That frequently ends up in the magnetic north vs true north conversation. I have to admit, I usually forget which side of that one I intend to come down on. Anyway, in addition to that, there are the potential problems like no signal or even a dead phone. So I keep a cheap compass in my kit.
Preparing for a trip, I decided to get a better traditional compass. I dropped in at Whole Earth Provision Co. We like to shop there for several reasons, but mainly we make a big effort to support dog friendly businesses. Consequently, Ridley likes to shop there as well.
I wasn’t looking for anything fancy, just durable. The guy behind the counter showed me something. It looked fine, it had the features I was looking for. Namely a little needle swinging around, and a big N. I looked down, and saw another one in the display case that looked exactly the same, but it was thirty dollars more.
So I asked, “What would I get if I spent another thirty bucks?”
He said, “It’s really exactly the same, except it’s a global compass and it works in both hemispheres.”
I know the look I had on my face. I’m sure I always have it the split second before the blow takes place. I looked at the one in my hand and said, “This one only works in the northern hemisphere?”
He said, “Yep” or some other short appropriate affirmation.
Pointing at the global compass I said, “Do you have to make adjustments? Make settings?”
He said, “Nope, it just does it.” I felt pretty sure the look was still on my face.
I wasn’t sure what to say or what to believe. The only thing certain was I had this sudden vision of standing at the Cape of Good Hope not knowing which direction to go to end up at Heathrow airport.
My response was, “I’ll take the one that does both hemispheres.”
A few days later I relayed this story to a friend whose opinion I generally respect. He berated me with logic and was convinced that I had been taken advantage of. North is north and this was just a marketing ploy. I had to know.
As with so many things in life, the simplest explanation is the correct one. It turns out that if you hold a traditional compass upside down, it will not work. The needle suspension system allows it to bump into the housing. And, as physics would have it, in the southern hemisphere, you are standing upside down most of the time, or at least some kind of sideways. Within a few hundred miles of the equator, with careful positioning, you can get a northern hemisphere compass to work after crossing south. Any Son of Neptune worth his salt knows, you can’t take that chance.
So here’s to asking questions, tiny bits of information, and keeping your needle pointed to the big N.