Above the table was a handsome electrolier. To this, by means of a piece of string, he hung the petrol filled balloon so that it was suspended about a foot above the candle I had noticed on the table.
“You see,” he explained with a grin, “I light the candle and put it just below the balloon. You can spend the time—it might be half-an-hour perhaps—in imagining what is about to happen. The heat from this little candle will cause the petrol slowly to expand until it bursts the balloon. Then down comes the petrol on the candle and the whole house will be a roaring furnace in a couple of minutes. Do you understand?” and he laughed in my face.
I ground my teeth, but made no reply.
“Well, good-bye, Yelverton,” he said in a voice of affected cheeriness, and yet in triumph. “I wish you both a merry journey into the next world. Perhaps you’ll find her your soul-mate there. Who knows?”
Next instant he had switched off all the lights and left us alone.
Only that fatal candle flickered as gradually its heat was causing the fragile yellow balloon to expand to bursting point.
Soon it would explode and then we should both be burned alive. Nothing could possibly save us!
My heart sank. Once again, however, hope revived within me. I strove to tear myself free from my bonds. But it was useless.
I heard the front door close with a bang and then knew that the man who had entrapped us had left. No doubt he would be lurking in the vicinity in order to make sure of the result of his devilish handiwork.
I tried to rouse Thelma by calling to her. Apparently Humphreys had not troubled to bind her and if I could only awaken her she might be able to get help before it was too late. But I could not raise my voice above a hoarse whisper: no shrieks of mine could call assistance. And, I reflected, Thelma, even if she were not dead, must have been heavily drugged and would no doubt remain unconscious for some time. Humphreys would never have run the risk of leaving her free to move if she came to herself.