Maths of Celtic and African art Chris Budd

Knots have been around for a very long time They have many uses Climbing Fishing Sailing

They also appear in nature Enzyme DNA Vortices

Knots are central to Celtic and African art Celtic African

Book of Kells

How to draw simple Celtic Knots Start with a grid (5, 4) grid

(5,6)

(4,8)

(2,2) 2 (3,2) 1 (5,3) 1 (4,4) 4 How many pieces of string are needed?

Simple Celtic Knots are very similar to plaited mat sona drawings Sona … African sand patterns These are used to tell stories (3,4) (2,4)

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More advanced Celtic Knots are also based on a grid and a set of simple rules or

ABC Grid Corner Patterns Corner Edge

A (A B) First example B Notation

Get the Trefoil Knot.. Also called the overhand knot Two trefoils = one reef knot

B AAB (B A A B) Notation Second example

Get the Carrick Bend This is the simplest example of a Josephine Knot

… or even … A A A A B B B B C (A B A) (B C B) (A B A) Symmetry makes the best knots Notation Four reflexions One rotation

… producing the knot

We can also produce more advanced African knots … Such as the Chased Chicken design