"It seems so," answered Toto, shaking his shoulders, as if he were stiff.

"Are you going to let him go free, sir?" asked Masin, standing ready.

"If you do, he will be down the shaft, before you can catch him. These men know their way underground like moles."

"Moles, yourselves!" answered Toto in a growl, putting his head up above the level of the vault.

Masin measured him with his eye, and saw that he was a strong man, probably much more active than he looked in his heavy, mud-plastered clothes.

"Get up here," said Malipieri.

Toto obeyed, and in a moment he sat on the edge of the hole, his legs dangling down into it.

"Not so bad," he said, settling himself with a grunt of satisfaction.

"I like you, Master Toto," said Malipieri. "You might have thought that we really meant to kill you, but you did not seem much frightened."

"There is no woman in the affair," answered Toto. "Why should you kill me? And I can help you."

"How am I to know that you will?" asked Malipieri.

"I am a man of honour," Toto replied, turning his stony face to the light of the lanterns.

"I have not a doubt of it, my friend," returned Malipieri, without conviction. "Just now, the only help I need of you, is that you should hold your tongue. How can I be sure that you will do that? Does any one else know the way in through the drain?"

"No. I only found it to-night. If there is a day's rain in the mountains, and the Tiber rises even a little, nobody can pass through it. The lower part is barely above the level of the river now."

"How did you guess that you could get here by that way?"

"We know many secrets in our trade, from father to son," answered Toto gruffly.

"You must have lifted the boards, with the stones on them, to get out of the shaft. Why did you put them back in their place?"

"You seem to think I am a fool! I did not mean to let you know that I had been here, so I put them back, of course. I supposed that I could get out through the cellars, but you have put a padlock on the inner door."

"Is there any way of turning water into that shaft?"

"Only by filling the well, I think. If the Tiber rises, the water will back up the shaft through the drain. That is why the ancients who built the well made another way for the water to run off. When the river is swollen in a flood it must be much higher in the shaft than the bottom of the well, and if the 'lost water' were running in all the time, the air would probably make it back, so that the shaft would be useless and the well would be soiled with the river water."

"You evidently know your trade, Master Toto," said Masin, with some admiration for his fellow-craftsman's clear understanding.

"You know yours," retorted Toto, who was seldom at a loss, "for just now you talked of killing like a professional assassin."

This pleasing banter delighted Masin, who laughed heartily, and patted Toto on the back.

"We shall be good friends," he said.

"In this world one never knows," Toto answered philosophically. "What are you going to do?"

"You must come back with as to my apartment," said Malipieri, who had been considering the matter, "You must stay there a couple of days, without going out. I will pay you for your time, and give you a handsome present, and plenty to eat and drink. After that you will be free to go where you please and say what you like, for the secret will be out."

"Thank you," answered Toto without enthusiasm. "Are you going to tell the government about the treasure?"

"The Senator will certainly inform the government, which has a right to buy it."

To this Toto said nothing, but he lifted his legs out of the hole and stood up, ready to go. Malipieri and Masin took up their lanterns.

CHAPTER XI

Masin led the way back, Toto followed and Malipieri went last, so that the mason was between his two captors. They did not quite trust him, and Masin was careful not to walk too fast where the way was so familiar to him, while Malipieri was equally careful not to lag behind. In this order they reached the mouth of the overflow shaft, covered with the loaded boards. Masin bent down and examined them, for he wished to convince himself that the stones had been moved since he had himself placed them there. A glance showed that this was the case, and he was about to go on, when he bent down again suddenly and listened, holding up his hand.

"There is water," he said, and began to lift off the stones, one by one.

Toto helped him quickly. There were only three or four, and they were not heavy. When the mouth of the shaft was uncovered all three knelt down and listened, instinctively lowering their lanterns into the blackness below. The shaft was not wider than a good-sized old- fashioned chimney, like those in Roman palaces, up and down which sweeps can just manage to climb.

The three men listened, and distinctly heard the steady falling of a small stream of water upon the stones at the bottom.

"It is raining," Toto said confidently, but he was evidently as much surprised by the sound as the others. "There must be some communication with the gutters in the courtyard," he added.

"There is probably a thunderstorm," answered Malipieri. "We can hear nothing down here."

"If I had gone down again, I should have been drowned," Toto said, shaking his head. "Do you hear? Half the water from the courtyard must be running down there!"

The sound of the falling stream increased to a hollow roar.

"Do you think the water can rise in the shaft?" asked Malipieri.

"Not unless the river rises and backs into it," replied Toto. "The drain is large below."

"That cannot be 'lost water,' can it?"

"No. That is impossible."

"Put the boards in their place again," Malipieri said. "It is growing late."

It was done in a few moments, but now the dismal roar of the water came up very distinctly through the covering. Malipieri had been in many excavations, and in mines, too, but did not remember that he had ever felt so strongly the vague sense of apprehension that filled him now. There is something especially gloomy and mysterious about the noise of unexplained water heard at a great depth under the earth and coming out of darkness. Even the rough men with him felt that.

"It is bad to hear," observed Masin, putting one more stone upon the boards, as if the weight could keep the sound down.

"You may say that!" answered Toto. "And in this tomb, too!"

They went on, in the same order as before. The passage to the dry well had been so much enlarged that by bending down they could walk to the top of the rope ladder. Malipieri went down first, with his lantern.