I was just bending to lift it from the ground, when I was startled at feeling myself seized from behind.

“Ah! You are my prisoner!” cried a voice, which, in a moment, I recognised as that of Guibaud, who had evidently followed me into the house.

At first both my arms seemed pinioned, but not for long. In a few seconds I had recovered my breath, wrested my right arm free, and drawn my revolver.

It flashed across my mind that we were alone, and that it was imperative I should overpower him.

“Let me go, curse you!” I cried in French. “I give you warning that if you don’t I’ll fire into that box and blow you to the devil!”

“Do it,” he replied. “You would die too. I arrest you for the manufacture of explosives.”

“Don’t make too sure of your prey,” I said, at the same time taking him off his guard, and freeing myself by dint of a great effort.

In the dim uncertain light, I saw something lying upon the bench, and snatched it up. It was a hammer.

Sacré,” hissed Guibaud, “you shall not escape now I have caught you in the act,” and his dark form darted forward.