The tautline hitch (also known as the midshipman's knot, rolling hitch, and magnus hitch) is an adjustable knot. By sliding the knot up and down the standing part of the rope, the loop contained by the knot can be made as large or small as necessary. It is commonly used among campers to adjust the tensions in the lines supporting a tent. The standing part is attached to the tent, and the loop is placed around the stake.
This knot tends to slide on slippery or stiff rope, and you may need to adjust it if the objects it is tied to are frequently moved or jostled. If you are using it for your tent, simply tighten them before bed, and they should be fine until the next night.
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