More from Chalkdust
On the cover: Apollonian packing
David Sheard explores the rich mathematics and history behind the Apollonian packing, and the cover of issue 11
Top Ten: pictures of scorpions
The definitive chart of the best pictures of scorpions
How to make: a catastrophe machine
Make a catastrophe machine just like Zeeman's
Fermat Point by Suman Vaze
The maths behind Issue 02's cover
The joys of the Jacobian
Robert Smith? tells us how his favourite matrix saves lives
The Mpemba paradox
Why does warm water freeze faster than cold water?