young man, "I know
what I have to do, and all for me will end with two blows from a
poniard--one in the heart of him whom you know, and the other in your
own."

"Remy! Remy!" cried Diana, "do not say that. The life of him you
threaten does not belong to you--it is mine--I have paid for it dearly
enough. I swear to you, Remy, that on the day on which I knelt beside
the dead body of him"--and she pointed to the portrait--"on that day I
approached my lips to that open wound, and the trembling lips seemed to
say to me, 'Avenge me, Diana!--avenge me!'"

"Madame--"

"Therefore, I repeat, vengeance is for me, and not for you; besides, for
whom and through whom did he die? By me and through me."

"I must obey you, madame, for I also was left for dead. Who carried me
away from the middle of the corpses with which that room was
filled?--You. Who cured me of my wounds?--You. Who concealed me?--You
always. Order, then, and I will obey, provided that you do not order me
to leave you."

"So be it, Remy; you are right; nothing ought to separate us more."

Remy pointed to the portrait.

"Now, madame," said he, "he was killed by treason--it is by treason that
he must be revenged. Ah! you do not know one thing--the hand of God is
with us, for to-night I have found the secret of the 'Aqua tofana,' that
poison of the Medicis and of Rene the Florentine."

"Really?"

"Come and see, madame."

"But where is Grandchamp?"

"The poor old man has come sixty leagues on horseback; he is tired out,
and has fallen asleep on my bed."

"Come, then," said Diana; and she followed Remy.

CHAPTER LX.

THE LABORATORY.

Remy led the lady into a neighboring room; and pushing a spring which
was hidden under a board in the floor, and which, opening, disclosed a
straight dark staircase, gave his hand to Diana to help her to descend.
Twenty steps of this staircase, or rather ladder, led into a dark and
circular cave, whose only furniture was a stove with an immense hearth,
a square table, two rush chairs, and a quantity of phials and iron
boxes. In the stove a dying fire still gleamed, while a thick black
smoke escaped through a pipe fastened into the wall. From a still placed
on the hearth a few drops of a liquid, yellow as gold, was dropping
into a thick white phial. Diana looked round her without astonishment or
terror; the ordinary feelings of life seemed to be unknown to her who
lived only in the tomb. Remy lighted a lamp, and th