With one of these bricks I could blow the house to smithereens. I had used the stuff in Rhodesia and knew its power. But the trouble was that my knowledge wasn’t exact. I had forgotten the proper charge and the right way of preparing it, and I wasn’t sure about the timing. I had only a vague notion, too, as to its power, for though I had used it I had not handled it with my own fingers.

But it was a chance, the only possible chance. It was a mighty risk, but against it was an absolute black certainty. If I used it the odds were, as I reckoned, about five to one in favour of my blowing myself into the treetops; but if I didn’t I should very likely be occupying a six-foot hole in the garden by the evening. That was the way I had to look at it. The prospect was pretty dark either way, but anyhow there was a chance, both for myself and for my country.

The remembrance of little Scudder decided me. It was about the beastliest moment of my life, for I’m no good at these cold-blooded resolutions. Still I managed to rake up the pluck to set my teeth and choke back the horrid doubts that flooded in on me. I simply shut off my mind and pretended I was doing an experiment as simple as Guy Fawkes fireworks.

I got a detonator, and fixed it to a couple of feet of fuse. Then I took a quarter of a lentonite brick, and buried it near the door below one of the sacks in a crack of the floor, fixing the detonator in it. For all I knew half those boxes might be dynamite. If the cupboard held such deadly explosives, why not the boxes? In that case there would be a glorious skyward journey for me and the German servants and about an acre of surrounding country. There was also the risk that the detonation might set off the other bricks in the cupboard, for I had forgotten most that I knew about lentonite. But it didn’t do to begin thinking about the possibilities. The odds were horrible, but I had to take them.