*We’ve been sent a copy of Matthew Lane’s Power-Up: Unl*

**ocking the Hidden Mathematics in Video Games**, and despatched Aperiodical regular and video game fan Paul Taylor to review it.*We’ve been sent a copy of Matthew Lane’s Power-Up: Unl*

Any book on cryptography written for a more-or-less lay audience must inevitably face comparisons to *The Code Book*, written in 1999 by Simon Singh, the king of distilling complex subjects to a few hundred pages of understandable writing. While Singh’s book is a pretty thorough history of codes and codebreaking1 through the centuries with plenty of the maths thrown in, *The Mathematics of Secrets* is tilted (and indeed titled) more towards a fuller explanation of the mathematical techniques underlying the various ciphers. Although Holden’s book follows a basically chronological path, you won’t find too much interest in pre-computer ciphers here: Enigma is cracked on page seventy, and the name Alan Turing does not appear in the book.

- I will in this review unapologetically make no attempt to maintain any distinction between the terms code and cipher; cryptography, cryptanalysis and codebreaking, etc. [↩]

Snowflake Seashell Star is a new mathematical colouring book, by Alex Bellos and Edmund Harriss, aimed at the lucrative ‘grown-up colouring books’ market that’s sprung up recently, heavily intersected with people who are interested in maths – the book can be used as a regular colouring book, but contains lots of interesting mathematical things, and mathematicians will love it. I wouldn’t have expected anything less from maths adventurer Bellos and mathematical artist and tiling fan Harriss, whose personalities both come through in the book – from the beautiful illustration to the playful style (and there’s a sneaky Harriss Spiral in there too).

The first thing I did in order to properly review the book was check an important mathematical fact, in case anyone was worried. And yes, **everything in it is colourable using four colours or fewer**. Phew.