## Articles

**Chris Sangwin**tells you how to make your own set of

*Napier's bones*and perform mathemagic with an interactive checker board.

**Abigail Kirk**explores one of the formulae that carry his name.

**Tom Körner**'s explanation really is a piece of cake, served up with a hefty estimate of pi.

**Shahn Majid**met up with

*Plus*to explain.