“One dynamite cartridge would do it!” laughed Malipieri, as he looked at the huge stone.

“Thank you, sir,” answered Masin, taking the suggestion seriously.  “I have been in the galleys seven years, and that is enough for a lifetime.  We must try and split it with wedges.”

“There is no other way.”

They had all the tools necessary for the old-fashioned operation; three drilling irons, of different sizes, and a small sledge-hammer, and they went to work without delay.  Malipieri held the iron horizontally against the stone with both hands, turning it a little after Masin had struck it with the sledge.  It was very exhausting after a time, as the whole weight of the tool was at first carried by Malipieri’s uplifted hands.  Moreover, if he forgot to grasp it very firmly, the vibration of the blow made the palms of his hands sting till they were numb.  At regular intervals the men changed places, Masin held the drill and Malipieri took the hammer.  Every now and then they raked out the dust from the deepening hole with a little round scoop made for the purpose and riveted to the end of a light iron rod a yard long.

Hour after hour they toiled thus together, far down under the palace, in the damp, close air, that was cold and yet stifling to breathe.  The hole was now over two feet deep.

Suddenly, as Masin delivered a heavy blow, the drill ran in an inch instead of recoiling in Malipieri’s tight hold.

“Bricks,” said Masin, resting on the haft of the long hammer.

Malipieri removed the drill, took the scoop and drew out the dust and minute chips.  Hitherto the stuff had been grey, but now, as he held his hand under the round hole to catch what came, a little bit of dark red brick fell into his palm.  He picked it out carefully and held it close to the bright unshaded lamp.

“Roman brick,” he said, after a moment.

“We are not in Milan,” observed Masin, by way of telling his master that he did not understand.

“Ancient Roman brick,” said Malipieri.  “It is just what I expected.  This is part of the wall of an old Roman building, built of bricks and faced with travertine.  If we can get this block out, the worst will be over.”

“It is easier to drill holes in stone than in water,” said Masin, who had put his ear to the hole.  “I can hear it much louder now.”

“Of course you can,” answered Malipieri.  “We are wasting time,” he added, picking up the drill and holding it against the block at a point six inches higher than before.

Masin took his sledge again and hammered away with dogged regularity.  So the work went on all that day, and all the next.  And after that they took another tool and widened the holes, and then a third till they were two inches in diameter.

Masin suggested that they might drive an iron on through the brickwork, and find out how much of it there was beyond the stone, but Malipieri pointed out that if the “lost water” should rise it would pour out through the hole and stop their operations effectually.  The entrance must incline upwards, he said.