I've got this funny little gadget which is a bit like a Pedometer only it's not a huge wheel, and you don't have to push it in front of you whilst you're walking. What you do is, you set your step length (0.54m) and your weight (not telling) and then you press 'go', clip it onto your belt and it tells you a/how far you have walked, b/how many steps it took and c/how many calories you burned doing it.

It's a great thing to have for walking the dog because it makes you feel like you are achieving some sort of personal fitness level whilst you're doing it.

Today I walked 3.58km, which was 6650 steps and I burned 250 calories, which isn't very many. That's equivalent to, at the very most, 1 piece of not very fattening cake.

Anyway, it's a really clever pice of tiny technology. I don't know exactly (or at all) how it works but it certainly has something to do with movement, because you can't just press 'go' and go nowhere because if you do the data doesn't change. We've experimented. You have to move (or shake the thing about) to make the data change which has to mean it records actual movement rather than time.

I am totally foxed by it. Today I said to Harry, mid-walk, "I really don't know how this works. It's very clever. How does it know how far I am going?"

I wasn't really expecting an answer. But he looked at me and said in all seriousness, "Perhaps it's got tiny eyes which we can't see, and it's counting really quietly."

Yes.

Perhaps it is.

And you know? I much prefer the idea that there is a litle gremlin inside the machine, secretly looking where we are going and counting my steps really quietly to any suggestion that there is a serious technological explanation for how the thing works.

I'd far rather support his reasoning than subscribe to one of those dull yet sensible rational scientific explanations.

Wouldn't you?