“What can they be doing?”

“I can’t think.”

“Can you see them?”

“They are too near the wall.”

“I think I can manage,” said De Catinat.  “I am slighter than you.”  He pushed his head and neck and half of one shoulder through the gap between the bars, and there he remained until his friend thought that perhaps he had stuck, and pulled at his legs to extricate him.  He writhed back, however, without any difficulty.

“They are building something,” he whispered.

“Building!”

“Yes; there are four of them, with a lantern.”

“What can they be building, then?”

“It’s a shed, I think.  I can see four sockets in the ground, and they are fixing four uprights into them.”

“Well, we can’t get away as long as there are four men just under our window.”

“Impossible.”

“But we may as well finish our work, for all that.”  The gentle scrapings of his iron were drowned amid the noise which swelled ever louder from without.  The bar loosened at the end, and he drew it slowly towards him.  At that instant, however, just as he was disengaging it, a round head appeared between him and the moonlight, a head with a great shock of tangled hair and a woollen cap upon the top of it.  So astonished was Amos Green at the sudden apparition that he let go his grip upon the bar, which, falling outwards, toppled over the edge of the window-sill.

“You great fool!” shrieked a voice from below, “are your fingers ever to be thumbs, then, that you should fumble your tools so?  A thousand thunders of heaven!  You have broken my shoulder.”

“What is it, then?” cried the other.  “My faith, Pierre, if your fingers went as fast as your tongue, you would be the first joiner in France.”

“What is it, you ape!  You have dropped your tool upon me.”

“I!  I have dropped nothing.”

“Idiot!  Would you have me believe that iron falls from the sky?  I say that you have struck me, you foolish, clumsy-fingered lout.”

“I have not struck you yet,” cried the other, “but, by the Virgin, if I have more of this I will come down the ladder to you!”

“Silence, you good-for-naughts!” said a third voice sternly.  “If the work be not done by daybreak, there will be a heavy reckoning for somebody.”

And again the steady hammering and sawing went forward.  The head still passed and repassed, its owner walking apparently upon some platform which they had constructed beneath their window, but never giving a glance or a thought to the black square opening beside him.  It was early morning, and the first cold light was beginning to steal over the courtyard, before the work was at last finished and the workmen had left.  Then at last the prisoners dared to climb up and to see what it was which had been constructed during the night.  It gave them a catch of the breath as they looked at it.  It was a scaffold.