It was an adventure which required a good deal of courage, but not one of the girls flinched. Isabelle, one of the oldest of the demons, claimed her right to go first, and accomplished her dangerous feat with the resolution of a heroine. Mary followed with the calm of a gymnastic professor, the remainder as best they could, but somehow or other they all managed to arrive safely on the staircase. At the foot was another little hall or room, without door or window or issue of any kind; but this, for some strange reason, caused the girls more joy than regret.

'Certainly,' they said, 'nobody would make a staircase which went nowhere! There must be some way out and we have got to find it.'

So the little taper was divided into several parts and each girl began a careful examination of the walls, pressing the plaster, which they hoped might conceal a ring or a button that, if touched, would reveal an opening. What would have happened if a sudden blast had blown out their candles, they never thought, for they had no means of lighting them again; and, of course, none of the Sisters had the slightest idea where they might be. Happily this did not occur, and though the surface of the walls was perfectly smooth, Isabelle declared that when she tapped the part under the staircase it sounded hollow.

This discovery threw the whole party into a state of wild excitement.

'We have found it at last!' they cried; 'this staircase leads down to the cell where living victims have been buried.' They jostled each other so as to place their ears against the wall, but strange to say, in spite of their fervent wish, they were compelled to confess that they heard nothing. All, that is except Isabelle, who persisted in declaring that they must every one of them be deaf, as the sounds of groans and clanking chains were quite plain.

'Then we must break down the wall,' said Mary, 'and the sooner we begin the better.'

In an instant the wall was attacked by the collection of arms the girls had brought with them. Tongs, pokers, shovels were all brought into play, but luckily without making any impression on the stones, which otherwise might have come rattling about their heads. Besides, the demons dared not make too much noise, for they were afraid of being heard, as they did not know exactly in which part of the convent they might happen to be.

Only a few pieces of plaster had fallen when the warning bell for prayers clanged through the building. How they contrived the upward climb from one balustrade to another, they never knew, and that they were able to do it at all was almost a miracle. Down they dashed along the passages, brushing the plaster from their dresses as they ran, and arrived breathless as the two classes were forming to enter the chapel.

During the whole winter they worked at the wall, but, persevering though they were, the obstacles encountered were so many that at length they decided it was sheer folly to waste more time on it, and they had better try to force an entrance by some other way.