"I have certainly done some careless thing like that which will
betray me yet; I wonder what it is?"

He wrenched the door open at last. The lights in the hall were out; he
struck a match, and made his way down. He thought he heard groans. As
he went down, he found it was the _concierge_ huddled in a corner.

"What is the matter?" he asked.

"Oh, my God, my God!" cried the _concierge_, "I knew they would do
it. We are all blown to atoms!"

"Get up," said Dupré, "you're not hurt; come with me and see if we can
be of any use."

"I'm afraid of another explosion," groaned the _concierge_.

"Nonsense! There's never a second. Come along."

They found some difficulty in getting outside, and then it was through
a hole in the wall and not through the door. The lower hall was
wrecked.

Dupré expected to find a crowd, but there was no one there. He did not
realise how short a time had elapsed since the disaster. The policeman
was on his hands and knees in the street, slowly getting up, like a man
in a dream. Dupré ran to him, and helped him on his feet.

"Are you hurt?" he asked.