Marzio entered the inner studio when Gianbattista was gone, leaving a boy who was learning to cut little files—­the preliminary to the chiseller’s profession—­in charge of the outer workshop.  The artist shut himself in and bolted the door, glad to be alone with the prospect of not being disturbed during the whole afternoon.  He seemed not to hesitate about the work he intended to do, for he immediately took in hand the crucifix, laid it upon the table, and began to study it, using a lens from time to time as he scrutinised each detail.  His rough hair fell forward over his forehead, and his shoulders rounded themselves till he looked almost deformed.

He had suffered very strong emotions during the last twenty-four hours—­enough to have destroyed the steadiness of an ordinary man’s hand; but with Marzio manual skill was the first habit of nature, and it would have been hard to find a mental impression which could shake his physical nerves.  His mind, however, worked rapidly and almost fiercely, while his eyes searched the minute lines of the work he was examining.

Uppermost in his thoughts was a confused sense of humiliation and of exasperation against his brother.  The anger he felt had nearly been expressed in a murderous deed not more than two or three hours earlier, and the wish to strike was still present in his mind.  He twisted his lips into an ugly smile as he recalled the scene in every detail; but the determination was different from the reality and more in accordance with his feelings.  He realised again that moment during which he had held the sharp instrument over his brother’s head, and the thought which had then passed so rapidly through his brain recurred again with increased clearness.  He remembered that beneath the iron-bound box in the corner there was a trap-door which descended to the unused cellar, for his workshop had in former times been a wine-shop, and he had hired the cellar with it.  One sharp blow would have done the business.  A few quick movements and Paolo’s body would have been thrown down the dark steps beneath, the trap closed again, the safe replaced in its position.  It was eleven o’clock then, or thereabouts.  He would have sent the workmen to their dinner, and would have returned to the inner studio.  They would have supposed afterwards that Don Paolo had left the place with him.  He would have gone home and would have said that Paolo had left him—­or, no—­he would have said that Paolo had not been there, for some one might see him leave the workshop alone.  In the night he would have returned, his family thinking he had gone to meet his friends, as he often did.  When the streets were quiet he would have carried the body away upon the hand-cart that stood in the entry of the outer room.  It was not far—­scarcely three hundred yards, allowing for the turnings—­to the place where the Via Montella ends in a mud bank by the dark river.  A deserted neighbourhood, too—­a turn to the left, the low trees of the Piazza de’ Branca, the dark, short, straight street to the water.  At one o’clock after midnight who was stirring?  It would all have been so simple, so terribly effectual.