Page 122 - Patrick Moreau-Marine "Knots How to Tie 40 Essential Knots"

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your hands.

In the era of sailing ships, bosuns used this knot to tie their famous whistle
around their neck, which they used to give orders from the mast.

1 and 2 - First step: the two strands pass between your fingers and turn around each other to the left without
crossing.

3 - After leading the right strand under itself to its starting point, lead the lower strand in the same way:
under, over, and under itself.