Page 109 - Peter Randall "The Craft of the Knot.."

STEP 2 Pull the center of the bight or belly through the center part of
the spine.

STEP 3 Tighten the loop.

The Dropper Loop can be used to position additional flies, weights, or
hooks along a fishing line.

FISHERMAN’S KNOT

Even though this is really a bend, it is known as the Fisherman’s Knot,
Englishman’s Knot, and the Angler’s Knot.

STEP 1 Lay two ropes parallel to each other and overlap each rope’s
running end around the other’s standing part, making two Overhand
Knots.