What was the biggest bang in the world?

Working from the dawn of time up to date, including volcanoes, crashing comets, and man made explosions.

Including some that have yet to happen…

Big - but not the biggest!

An introduction to secret writing – and secret talking!

Sherlock Holmes solved this one. Would you know how to start?

“Shave his head!” - Elizabeth I and her spy network - the basics, substitution, transposition, grilles and invisible writing - Pig-pens and Dancing Men - the Genius of al-Kindi and ETAOIN SHRDLU - rods, wheels and discs - Polish help with Enigma - Colossus, the first real computer - rhyming slang, Dog Latin and code talkers - computer enciphering, and an unbreakable cipher using a public key!