Follow the Lines

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Published on: Jun. 2, 1997

Last revision: Oct. 26, 2010

and savvy group; they often refer to their sport as "cunning running."

The orienteering compass not only has the obligatory needle that points north, but also features a housing marked in 360° increments and an orienteering arrow etched on the bottom that can be rotated independently of the needle. These features are usually supported on a see-through base plate that has its own fixed arrow and an index mark for the housing.

Thanks to the earth's magnetic field, your needle always points north. (More on this later.) If you align the needle with the fixed arrow on the base plate of the compass and turn the base plate so 0° (north) is at the index line and trek off that way, you are trekking toward magnetic north and, given the inclination, could continue on your bearing of 0° all the way to Canada's Hudson Bay.

Let's say your travel plans were more limited, and you only needed to cross a timbered valley. You can see the lodge that is your destination from your ridge top, but once among the trees you'll lose your landmark.

To find a compass bearing that you can follow to the lodge, all that's necessary is to face the lodge and point the base plate arrow toward it. The floating arrow will still point north and you should then turn the housing to align the arrow on the bottom with the floating arrow. The number at the index mark will be your bearing.

Now, when you're in the thick stuff, all you have to do to remain on course is line up or orient the needle and the orienting arrow again, making sure that the same number is at the index mark. The base plate of the compass will now point out your line of travel.

If you try to travel while staring at the compass, you'll likely get a twig in the eye and scuffed up shins. Better to stop, use the compass to find a visible landmark-a distinct tree or rock, for example-and travel to it, then use the compass to find another landmark on the same bearing.

Because straight line travel is difficult, even under perfect conditions, use every opportunity, for example a forest opening or a rock promontory, to adjust the bearing to your eventual target.

Once you know the bearing from one object to another, you can always head toward it, even in dense fog or at night, and

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