At least, it looked like a chameleon. The only thing he knew about the species was that they were supposed to change colour to blend in with their background. If this one was real, shouldn’t it be light grey, like the material covering the floor of the terrarium? Or a dark pine colour, like the varnish on the shelving?

While Cooper watched, it didn’t so much as blink. Was it actually alive?

‘The ashes came in a plastic urn,’ said Mrs Askew. ‘We decided to do something a bit different and display them. He would have liked it, I think.’

At first, Cooper didn’t know what she meant. Then his gaze strayed past Mrs Askew’s head to the bookshelves. He thought the chameleon had moved, perhaps raised a front leg to allow the passage of air under its belly. It might only have been a slight shift that had attracted his attention. Or it could have been the realization that the material on the floor of the terrarium was a light grey, granular material, like fine cat litter.

Mrs Askew followed the direction of his gaze. ‘Seven pounds of ashes go a surprisingly long way,’ she said. ‘There were even a few ounces left over, so I shared them out into a set of little brass boxes that I found in an antique shop near the Buttercross. I gave a box to each of his grandchildren. That’s the best way to be remembered, I think – to have your memory passed down through the generations of your own family. Don’t you agree?’

‘Yes, I’m sure you’re right.’

Of course, Cooper had immediately thought of his own father. It was an instinctive reaction when someone mentioned keeping the memory of a family member alive. It didn’t seem to trouble him the way it once had. He found he could even think of the practicalities – whether it would have been better if Sergeant Joe Cooper had been cremated, rather than buried in Edendale Cemetery. And how much his ashes would have weighed, if he had. More than eight pounds, certainly. Plenty to have shared out into little boxes for everyone. And then, perhaps, his father’s memory wouldn’t have weighed quite so heavily on one pair of shoulders.

There were several Venus flytraps growing in the other terrarium. Cooper could see their thick triangular bases and the teeth on their traps. They looked capable of ensnaring something the size of a bumble bee, let alone a fly.

‘Do you know anything about carnivorous plants?’ asked Mrs Askew, noting his gaze and assuming interest, the way people did.

‘No. Do they catch many flies?’

‘Each leaf can catch and digest three meals before it dies,’ said Mrs Askew. ‘Leaves can open and close without catching anything, but eventually they exhaust themselves.’

‘Only three meals in their lives? No matter how big they are?’