Page 87 - J. C. Turner "History and Science of Knots"

76 History and Science of Knots

The Spacial Layout
The backbone of a quipu is the main cord, which is usually thicker than the
other cords. Attached to it are the pendant cords. There can be as few as three
or as many as two thousand of these. Some cords fall in the opposite direction,
they are called top cords. Top and pendant cords can have subsidiaries, which
can again have subsidiaries, and so on, so that a tree structure occurs.

main cord

I
attaching method overhand knot

pendant

subsidiary
Q four fold long knot figure eight knot

Fig. 3. Quipu Knots (attaching method, overhand knot, four fold long knot and
figure eight knot adapted from [9], p. 16)
There can be up to six different levels and up to ten subsidiaries per level.
The pendants, top cords and subsidiaries are the cords which carry the knots.