Two square triquetras joined sideways with a common break give a Forma Formarum Knot.

Two turned about, with breaks on opposite sides, gives us the Josephine Knot.

Other knots on the first page are derived from the basic knot, using "L-breaks" in a four cord braid,  forming single-spiral knots, and "Z" breaks, making double-spiral knots.

These basic variants on the simplest knots  may be found on the first pages of the Book of Kells, used as birds' necks and tails.

The  simplicity of these patterns at the start of the book contrasts with the more difficult ones that follow.

In the Book of Kells, on  two,  two birds' necks form a Josephine knot at the top of the centre pillar of a row of archways. This knot is made from two basic knots, fused together to make one knot.