Page 65 - Cliff Jacobson - Outdoor Knots

Figure 34. Square (Reef) Knot

For centuries sailors have used the square knot for reefing sails and tying things
aboard ship. It is still used for this purpose but probably more popular for tying
packages, gauze dressings, tourniquets, and other medical applications. Don’t
use this knot for joining two ropes together if they will be under load! The
square knot jams under tension and falls apart (it becomes two half hitches) if
the ropes are very dissimilar or the pull comes unevenly. Use a sheet bend,
fisherman’s knot, or two bowlines for joining ropes. To form a square knot rather
than a common granny knot, complete each overhand knot opposite the other.
Thus, if the first knot is formed right-handed (right over left), the second must be
made left-handed (left over right).