It was an ancient alley door, low, vaulted, narrow, solid, entirely of oak, lined on the inside with a sheet of iron and iron stays, a genuine prison postern. The blows from the butt end of the gun made the house tremble, but did not shake the door.

Nevertheless, it is probable that the inhabitants were disturbed, for a tiny, square window was finally seen to open on the third story, and at this aperture appeared the reverend and terrified face of a gray-haired old man, who was the porter, and who held a candle.

The man who was knocking paused.

“Gentlemen,” said the porter, “what do you want?”

“Open!” said Cabuc.

“That cannot be, gentlemen.”

“Open, nevertheless.”

“Impossible, gentlemen.”