When I was growing up in England, I didn’t have a chemistry set, but I did have a television set, and on that television set, once a week for what seemed like an age, a man called Johnny Ball would appear and tell me about all manner of science subjects, from geology to biology to physics and astronomy. A presenter of preternatural energy, Ball was a marvellous entertainer whose enthusiasm for his subject was obvious and whose ability to convey often complex ideas with the aid of eccentric and implausible gizmos remains, as far as I know, unsurpassed. He was, and indeed still is, regarded with enormous affection in the United Kingdom—an affection given extra depth for my generation of thirty-somethings by the fact that he had also presented Play School and thus seems, in a benign way, to have presided over whole childhoods. But the real reason for Ball’s popularity is that he managed to instil a love of science. A one- man Enlightenment, he kindled our interest.

And the flame continued to burn, for a while. It burned in the form of Mrs Maclaren, who took us for chemistry lessons at school. In fact, ‘burned’ is precisely the word. For Matches Maclaren could not go an hour without burning something, usually a little strip of magnesium, which, when held over a Bunsen flame, would flare up suddenly into a brilliant white nova. Or else she would take a small ball of sodium and place it in a water-filled dish, where it skipped and fizzed and whizzed around, slowly dissolving to nothing as it did so. I can’t recall the point of these experiments but I do remember loving them and being more than a little upset when Mrs Maclaren was pensioned off and replaced by a teacher whose name I forget but whose lugubrious demeanour and patchy beard made me feel strangely queasy.