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Prusik Hitch
The Prusik hitch (Figure 11) is a friction hitch used both in climbing
and rigging applications. It is bidirectional in some applications. A
smaller-diameter rope is used to attach the Prusik to a working line.
The type of rope affects how the knot will work, so it is important to
test rope-on-rope combinations before using.
To tie: Hold a fixed loop
behind a line and pass the bight from one side through the other side
two or three times. It now forms a hitch that will lock securely when
pulled in either direction along the line. It also can be tied with a
single piece of rope.
Valdôtain Tresse and Machard Tresse
The Valdôtain tresse (Vt) and Machard tresse (Mt) are variations of the French Prusik.
They are friction hitches with application in rigging and climbing. The
Machard tresse is tied with a fixed loop, while the Valdôtain tresse
(Figure 12) is tied with a single piece of rope, with knots or splices
in either end.
To tie: Either hitch is tied in the same way. The
standard form consists of four wraps covered by three braids. Start with
the loop or cord on the front of a line and make four counterclockwise
wraps down the line. Next, braid the two ends, with the end from the top
of the rope crossing over the lower end at the back of the line. The
second crossing is at the front with the top end underneath, and the
third crossing again at the back with the top end on the outside.
Butterfly
The butterfly (Figure 13) is a good knot for forming a midline
loop. It is symmetric, without extreme bends, and usually is easy to
untie after use.
To tie (Method 1): A single loop can be formed in the
bight with the butterfly. Begin with a bight and impart a 360-degree
twist. This move forms two crossings of the legs of the bight. Now fold
the bight down to the front, push it down between the legs of the bight,
and then up between the two crossings identified earlier.
To tie (Method
2): With your palm facing up, make three turns around your hand. Pick up
the turn on the left and place it between the other two. Pick up the
turn that is now on the left and place it to the right of the other two,
then take this same turn, which is now on the far right, and pass it
under and up between the two other turns, passing it from right to left.
Pull it through to make a loop, then dress and set the knot.
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International Society of Arboriculture
