Page 117 - Buck Tilton - Outward Bound Ropes, Knots, and Hitches 2 ed.

Take the working end through the second loop
and tighten by pulling on the standing part. The

knot can now be pushed up the standing part,
taking slack out of the rope. Under pressure, the
knot grips and holds against the standing part,

maintaining tension in the rope.

Timber Hitch

TEMPORARILY ATTACHES A ROPE TO AN OBJECT FOR
DRAGGING, RAISING, OR LOWERING

A fundamental knot, the timber hitch serves as a short-term

noose, quickly tying a rope to a heavy object that needs to
be moved by pulling, dragging, lifting, or lowering. It is very

secure under tension and never jams. But be careful: Those
new to knots often tie this one incorrectly, and then the knot

fails. The timber hitch can also loosen and fail if there is too
much slack in the rope or erratic pulling on the rope.