When people first reached the North Pole, before GPS, they had to use a compass. How did they know when they reached the North Pole? How did they know when they reached the true North Pole as opposed to the magentic North Pole? Did the compass needle spin around crazily, or just stay pointed North no matter what? -Jakeofalltrades1964
As I recall, from reading about Polar expeditions past, the needle moves very slowly, or tends to point down. Solar observations are necessary to determine one’s position.
No. People have long understood that compasses were worthless in the far North.
When the elevation of the Sun in the sky didn’t change in the course of a day.
Compass needles follow the force lines of the Earth’s magnetic field. The force lines behave erratically as you near the magnetic poles, so a compass will point hither and yon without much pattern.
At the North Pole, a compass will give the direction of Chicago. This is not a joke – at 90 degrees North, a compass will point in the direction of the North Magnetic Pole – which happens to be on the same meridian as Chicago.
Wikipedia claims that (in 2005) it was closer to the latitude of Calgary and trending west.
I blame Ed Zotti.
Doesn’t this presuppose that they were visiting on an equinox?
Longitude? Latitude is how far north or south. Or have I got those mixed up?
Maps I’ve seen put the north magnetic pole on Victoria Island in the Arctic Islands. There, a compass would point down, assuming it was pivoted appropriately. I seem to recall that this is known as ‘dip angle’.
No. On an equinox the Sun will stay at the same altitude all day, but will be on the horizon. In mid-summer, it will stay on the horizon, but at a 23.5 degree altitude. In winter… well, winter at the north pole is kind of a drag.
If you’re very curious, read the wikipedia articles on the various polar explorations. What they did was take solar and stellar elevations, and plot them as they traveled, and they also used dead reckoning (figuring how fast they traveled, on average, for how long, on average,) all to prove, they were reasonably close to, or had at least passed, the pole. Nobody went there, to stick a barbershop pole in the ice and state, “It’s spinning around this point.” At least at the start of exploration.
Not if you’re Santa Claus. 
Establishing that you are actually at the North Pole is kind of tricky. Ask Richard Byrd. Note that they used sextant readings of the sun. It’s hard to do stellar readings unless you’re travelling in winter (which is of course not such a fun thing).
Okay, I got that my understanding was confused, and I get your explanation, but someone please tell me that this part is still confusing. 
The typo probably didn’t help much.
On any given day, the Sun will appear at some altitude off the horizon. How much depends on the time of year. It will appear to circle you once per day, but will stay at that same altitude.
That is something interesting I learned while preparing for my first trip to the southern hemisphere.
Strictly speaking, a compass needle does not point north or south; it aligns itself with the field lines of the Earth’s local magnetic field, which do not necessarily point straight to either the true or the magnetic north pole. In the south of Africa, for example, the difference between true north/south and the local magnetic field lines can be as great as 30 degrees. This is called the magnetic declination.
However, those magnetic field lines also have an angle towards the ground, which gets greater as you get closer to the poles. At the north or south pole, a free-floating magnetized needle would indeed stand straight up. This is called the inclination of the magnetic field.
When using a typical flat hand compass, the inclination can cause the needle to scrape the bottom of the compass housing, preventing it from rotating freely. Compass manufacturers know this, so they balance the needle so that it will work right in the latitudinal area where they expect it to be used. If you purchase a compass in Northern Europe and then use it while traveling through Southern Africa, you’ll have problems. More high-end compasses solve this problem by having a little bar magnet in the pivot axis, while the ‘needle’ itself is not magnetized and can dip up and down freely.
Whoops. You’re right; my mistake.