‘No, I don’t. Nine kilos of ammonium nitrate in your bedroom would have annihilated it and made a nasty hole all round, but I wouldn’t have thought it would bring half a house down. So if we locate the device in that foot-of-the-bed box, we are looking at something in the region of…’ he did some more calculations ‘… say at least seventy-five cubic metres for your father’s bedroom … that’s twenty-five kilos of explosive.’
‘That’s heavy,’ I said blankly.
‘Yes. A large suitcaseful. But then you’d need a suitcaseful also if you were using cordite. For demolishing this whole house, you’d have needed four times that amount, placed in about four places on the ground floor right against the thickest walls. People often think a small amount of explosive will do a tremendous lot of damage, but it doesn’t.’
‘What sets it off, then?’ I asked.
‘Ah.’ He smiled the professional smile that wasn’t about to give away its secrets. ‘Let’s just say fulminate of mercury, plus, I should say, an electrical circuit.’
‘Please do explain,’ I said.
He hesitated, then shrugged. ‘ANFO won’t explode on its own, it’s very stable.’
‘What’s ANFO?’ I interrupted.
‘Ammonium nitrate fuel oil. The first letters. ANFO for short.’
‘Oh yes. Sorry.’
‘So you stick into it a package of something that explodes fast: the detonator, in fact. Then you arrange to heat the detonating substance, either with a burning fuse, or by an electrical circuit which can be achieved by ordinary batteries. The heat sets off the detonator, the detonator detonates the ANFO. And bingo …’
‘Bang, you’re dead.’
‘Quite right.’
‘At four-thirty in the morning,’ I said, ‘it would probably be a time-bomb, wouldn’t it?’
Mr Smith nodded happily. ‘That’s what we’re looking for. If it was an alarm clock, for instance, we’ll probably find the pieces. We usually do if we look hard enough. They don’t vaporise in the explosion, they scatter.’
Thirteen
I drove unhurriedly to Epsom but as soon as I let myself into my flat, I knew I wouldn’t stay there. It was too negative, too empty, too boring. I wouldn’t live there much longer, I thought.
There were a few letters, a few bills, a few messages on the answering machine, but nothing of great interest. If I’d been blown up at Quantum along with Malcolm, it wouldn’t have made any vital difference to anybody, and I didn’t like that thought very much.
I went into the bedroom to see what I’d got left in the way of clothes and came to the white lace negligee. Well, maybe she would have been sorry for a while. I wished I could phone her, but it was forbidden: her husband would answer as he had once before when I’d tried, and too many‘sorry, I’ve got the wrong number’s would raise the suspicions of the dimmest of men, which he reputedly wasn’t.
Apart from her, I thought, making a mental inventory, I mostly knew a lot of racing people on the borderline between acquaintance and friend. Enough to be asked to parties, enough for contentment at work. I knew I wasn’t in general unpopular. It was enough, I guessed. Or it had seemed enough, up to now.
I had enjoyed being with Malcolm more than I’d realised. I missed him already, and in the twelve days I’d spent with him, I’d developed a taste for spontaneity which made sitting around in my flat impossible. I packed a pair of breeches and a sweater, added some limp old shirts to the new ones in the Simpson’s suitcase, closed up the flat and went down to the car-park.
My own car stood there, but I took the hired one again, meaning to turn it in some time and return for my own by train. First stop was at the bank to drop through the letter box an envelope containing Malcolm’s cheque, with a paying-in slip to lodge it in my account.After that, I set off again in the overall direction of Quantum, but without really knowing where I was going.
I felt an awful aversion to the task of searching the psyches of the family, but I ended up in a place from where visiting them all would be easy, taking by impulse a turn onto the road to the village of Cookham and booking a room there in an old inn friendly with dark oak beams and log fires.
Norman West was out. I phoned him on the hour at four and five and reached him at six. He said apologetically that he had stopped working on the Pembroke case, there