"Come in," Arthur said cheerfully. "I trust I did not hurt any of you. I merely wished to see whether my muscles were in working order. I find that they are quite right, thank you, and, having ascertained that, have come back to my cell. You can, if you like, shut the door again, for this room is rather draughty when it is open."

The door was immediately shut, and the bolts shot. Arthur wondered what the next move would be. No one came near him for two hours; then to his surprise he heard a grinding sound against the door, and half a minute later the head of an auger appeared. Another hole was made touching the first, then a fine saw was thrust through. This began to work, and presently a piece was cut out of the door some six inches wide and eighteen inches long. After a pause the piece was fitted in again. Next he heard a sound of screws being driven in, and then he saw that hinges had been fastened to the flap, so that it could be opened and closed from the other side at will. Then he heard two bolts fixed to it. The noise went on for some time, and he knew by the sound that two more bolts had been screwed on to the door itself.

He saw at once that the monks intended in future to pass his food in to him, instead of entering his cell. This proved to be the case. The flap was opened and his tray handed in, together with a basin of water. "They are determined that the monks shall not be exposed to assault and battery again," he laughed. "I have evidently given them a scare. Now, I have nothing to do but wait and see if anything comes of my note."

A fortnight of anxious waiting passed. His food, books, and water were handed in regularly, but no one entered his cell. He listened anxiously whenever he heard the slightest stir in the monastery that would tell him that search was being made, but no such sound met his ear. At last he came to the conclusion that his note could never have reached Leon's hands. Being but a scrap of paper, it might have escaped the eyes of passers-by and been trodden in the mud; or again, the prior might at once have suspected the reason of his strange conduct and despatched a monk to pick up the note. Several times he wrote the same message on pieces of paper, rolled them up into a small ball, and threw them through the window in the hope that some passer-by might be attracted by the sight of the pellet, and open it to see what was in it.

Till the end of a fortnight he remained patient, spending most of his time in reading; but when he finally determined that the letter had gone astray, he threw aside his books and decided that he must rely upon himself. It was evident that if he was to escape at all, it must be through the wall under the window. He had read of escapes by prisoners, and some of these had been performed in circumstances at least as difficult as those that confronted him, and with means no better than the knife he had in his possession. Much must, of course, depend upon the thickness of the wall and the materials of which it was built. He could see by the window that it must be at least two feet thick, and if constructed of solid blocks of stone there would be no possibility of getting them out, as his knife was but some six inches long in the blade, so that it would be necessary to wear the wall away into dust. Of course, if there were no other way, this is what he must attempt.

But for the precaution that had been taken to prevent his escape, this would not have been possible, for the monks, when they came in, could not have failed to notice the gradual crumbling away of the wall. There was, however, one other chance. As this was a subterranean, or almost subterranean room, there was not likely to be a vault under it; therefore it was probable that the wall was not continued far under the bottom of his cell. It might be one foot, it might be two, but the solid stonework would not go much deeper; it would rest upon a bed of concrete, or possibly of loose rubble. Once through that, he would probably find nothing but earth between him and the pavement above. These pavements were in most of the side streets mere cobble stones. He therefore set to work now to examine the stones forming the floor. They were about two feet square, and after some consideration he determined that the best to operate upon would be that at the foot of his bed, as this would be hidden from the sight of anyone looking through the trap. His greatest difficulty would be to get rid of the materials that must necessarily be removed. Stones he might manage to clear out by throwing them through the window with sufficient force to carry them across the street; earth, he finally concluded, he would have to dispose of in the same way.

In order to do this, however, he would have to reach the window. Of course, if he were certain that the cell would never be entered, he could pile it up against the wall to the right and left of the door, for the hole was too narrow to admit a head. However, this was a risk that he would not like to run. The excavation would occupy many weeks, possibly many months, and it was hardly likely that so long a time would elapse before a visit was made to his cell. After much thinking he concluded that if he took up two of the slabs, and placed one against the wall and the other upon it, he could just reach the window. Then, by fastening the end of a blanket to one of the bars, he could easily pull himself up by it and throw the mould outside.

This was certain to be slow work, and a few handfuls of soil scattered on the road would not be likely to attract any attention. Examining the floor carefully, he saw that the slabs of stone were by no means even, from which he concluded that they were not laid in cement, probably not even in concrete, but that the ground had been simply smoothed down and the flags laid on it, and perhaps hammered down. The cells had probably not been intended as living rooms, but were used as prisons, perhaps as far back as the days of the Inquisition.

Having once made up his mind and carefully examined the stones, Arthur lay down on the floor and prepared to act. He had just finished his breakfast and handed out the tray as usual, so he would not be disturbed again for at least four hours. He began with his knife to loosen the stone at the foot of his bed, which was on the left-hand side of the cell, and found to his satisfaction that the slabs were laid close together, but not so closely that the knife would not in most places go down between them.

The crevices were filled up with the dust of many years, and it took him till dinner-time to clear this out. He was gratified at finding, however, that while in some places his knife encountered stones when he thrust it deep, at other points he could push it down to the hilt without encountering any obstacle. This showed him that his conjecture was correct. The ground had simply been smoothed down, chips of stone from the building thrown upon it and mixed with the sand, and on this the paving had been laid down. Beyond the fact that his knife went lower than the bottom of the stone, he could not tell how thick the floor was, but he judged that it would probably be three or four inches. It was evident that he could not get this up by the mere leverage of the knife, and he would only break the tool if he attempted it.