Adrian, very tired at dinner.

We went to the Ahhaa science centre today. They had a spy themed exhibition with a lot of activities that we really enjoyed: recognizing fingerprints and tire tracks, trying out an airport-style baggage scanner and a hand-held metal detector to find fake guns and such, climbing and crawling through a dark corridor criss-crossed with green laser beams, and a “stepping stones” memory game (just like the entrance to El Macho’s lair in Despicable Me 2) and so on.

We also saw an awesome “science theatre” show about the chemistry of fire, which was basically a demonstration of lighting things on fire, and of different ways of making the fire burn stronger and faster. I love fireworks and explosions – at a safe distance.

The fires ranged from tame (a cotton ball in normal air) to really impressive fireballs (a propane-filled balloon). The final fireball (another balloon containing a mixture of 1 part propane and 5 parts pure oxygen) was such that all members of the audience were first instructed in the proper technique of covering their ears, and the presenter wouldn’t proceed until everybody was following those instructions. It made a very satisfying bang and the heat could be felt several rows away.