I do not think Professor Murray Campbell would be insulted if I said that he was not a big man, any more than I would be insulted should someone point out that I was not a big man either, or that I was rather lacking in hair.

My former university tutor arrived at the Scottish Schools Education Research Centre (SSERC) a couple of Fridays ago to contribute to one of our physics continuing professional development events. Lifting the tailgate of his unostentatious Ford Focus, he began to unload a boot’s worth of well-travelled instrument cases. Musical instruments, not scientific measuring instruments.

Professor Campbell has the distinction, if that’s the word, of having taught both my wife and me, as his speciality is the physics of music. As he passed through the lunching course participants to set up in our training room, he left a frisson of expectation and intrigue in his wake. What was going to happen here? Sandwiches were finished, coffees downed and order came from chaos as the teachers headed to their seats.

I know that I was not alone in finding the lecture that followed quite wonderful. Professor Murray managed never to let the physics spoil the beauty of music, nor did his gentle showmanship relegate the science to, er, second fiddle. He sang a sine wave. Made a hose and funnel sound like a trombone. Played a variety of strange instruments. Spontaneous applause. Permanent grins. A sense that, like a good tune, he was still there when it was over.

At one point, Professor Campbell took the workings of a musical box and let it play. We could hear almost nothing. Then he sat it on a wooden table and the sound filled the room.

I’ve seen this sort of thing happen with teachers and indeed lecturers. Somebody appears quiet and unassuming. You wonder if they will be able to make their presence felt in a classroom. But they have a passion, perhaps for their job, perhaps for a subject (Ooh, the love that dare not speak its name), maybe even for social justice or for all three. They are not only present in the room, they fill it.

I reckon that even when at my best as a teacher, there were times when I not only felt that I wasn’t filling my classroom, I seemed to be barely present at all. I look back at these times as if from the viewpoint of a third person and can hardly spot myself among the bobbling heads of my pupils. But that’s a sad song from another time. The song that’s going through my head just now tells me that a good physics lecture makes you glad to be a physicist. A wonderful one makes you glad to be human.

Gregor Steele gave all the participants in the CPD course a Stylophone.

Gregor Steele, Scottish Schools Education Research Centre.