Oliver thought for a moment. "I would have you let me go from here safe and sound," said he.
"Very good," said the other. "And what else?"
"That you promise I shall suffer no harm either from you or your servant Gaspard."
"That you tell me the secret of that dreadful place where I have been."
"That you show me the virtue of this water."
"That you let me have half the gain that is to be had from it."
Oliver thought for a moment or two. "Why this!" said he; "that you tell me why you sought me out at Flourens, and how you knew that I had escaped from that pit into which you had locked me."
Oliver thought for another little while. "Nothing else," said he at last.
Once more the other laughed. "If I refuse," said he, "you throw those bottles out of the window?"
"And if I promise," said he, "what then?"
"I will give to you those bottles that you seek," said Oliver.
The other laughed. "Do you not trust that?" said he. "No? By what, then, shall I promise?"
A sudden flash of recollection passed through Oliver's mind, a sudden inspiration came to him. "Promise by this," he cried, in a ringing voice--
and he drew the figure which he had seen depicted upon the red line around the door-way at the bottom of the stone steps--the line that had kept back Gaspard and his master like a wall of adamant. The other's face grew as black as thunder. There was a sharp click--he had crushed the glass in his hand to fragments. A drop of blood fell from his palm upon the table-cloth, but he did not seem to notice it.
"Promise by that?" said he, a little hoarsely.
The other swallowed as though a hard lump were in his throat. "Very well," said he; "I promise."
Oliver saw that the promise would be kept. He closed the window near to which he stood. When he turned around, the other's face was smooth and smiling again.
"And now sit down," said he, "and let us finish our little supper, then I will tell you the story of those rooms yonder, and of the dead lady whom you found there."
The master drew his chair a little more around towards the fire, and drawing a gold toothpick from his waistcoat pocket, settled himself comfortably. "Did you ever hear," said he, "of a certain Spaniard, a very learned man, a great philosopher, and a renowned alchemist, named Raymond Lulli?"