"That's where the real story comes in," his mother explained. "You know there is a long passageway between the front rooms of the Fernbloms and their kitchen in the rear. It runs back of the stairs. The next time you go through it, stamp your foot very hard, and you will hear that it sounds hollow in one place. At that spot there used to be a trap door in the floor. Now it is nailed down hard, but in the old days it could be opened any time, and then you found a stairway below. It led into our part of the cellar, where you still can find a couple of stone steps at one end. Then the conspirators went down into the main cellar, and at the back of it there was a tunnel leading under the rear part of the house and the lane beyond to a house on the other side. That's the way they escaped, and that's why the police never found anybody in the club."
"What did the conspirators want," asked Keith after he had pondered the matter for a while.
"I don't know exactly," his mother admitted, "but the king was killed by one of them at last."
"I wish I had been there to defend the king," said Keith. Then a new thought seized him suddenly: "I want to go down and see those steps."
"All right," his mother answered to his astonishment and joy. "Lena will soon go down to get potatoes for dinner, and then you can go along, if you only promise to come right up again."
Shortly afterwards the momentous expedition actually took place. Keith had been as far as the outer cellar door before, but he had never cared to go further. When you opened that door, you were met by an air so cold and damp that it struck your face like a wet sheet, and the stairs fell away into a black abyss that seemed bottomless.
The door was of iron, rounded at the top to fit the arch, and covered with rust. It looked as if it had been in its place since the house was built, and Keith had heard that the house could not be less than two hundred years old. The key, which Keith had been permitted to carry going down, was of iron too, and nearly twice as long as Keith's hand. The lock was in keeping with the key, enormous in size and so stiff that Lena had to use both hands to turn the key.
Having laid a firm hold of Lena's skirt, Keith followed her several steps down until they reached a place in the opposite wall where a single very tall step led up to another iron door, square-cut and narrow, back of which lay the cellar used by the Wellanders. Lena lighted a candle that burned with difficulty in the clammy air.
Inside nothing could be seen at first but a number of boxes and barrels full of supplies, and back of them walls built out of enormous stone blocks and dripping with moisture. As his eyes became accustomed to the dim light, however, Keith perceived that the end toward the lane was closed by a wall which even his inexperienced glance recognized as brick and comparatively new. Squeezing between two large barrels of potatoes he saw two stone steps at the foot of that wall and managed actually to put his foot on one of them.
"I wish I knew what's back of that wall," he remarked at last.