Do you
think it will succeed? Are you sure it will do no harm?"

"Quite sure. Come, and see me measure it out."

"One moment! It is past eleven now. How long will it be before anything
happens?"

"It is not easy to say. An hour perhaps."

"I suppose the room must be dark, as it was last year?"

"Certainly."

"I shall wait in my bedroom--just as I did before. I shall keep the door
a little way open. It was a little way open last year. I will watch the
sitting-room door; and the moment it moves, I will blow out my light. It
all happened in that way, on my birthday night. And it must all happen
again in the same way, musn't it?"

"Are you sure you can control yourself, Miss Verinder?"

"In HIS interests, I can do anything!" she answered fervently.

One look at her face told me that I could trust her. I addressed myself
again to Mr. Bruff.

"I must trouble you to put your papers aside for a moment," I said.

"Oh, certainly!" He got up with a start--as if I had disturbed him at a
particularly interesting place--and followed me to the medicine-chest.
There, deprived of the breathless excitement incidental to the practice
of his profession, he looked at Betteredge--and yawned wearily.

Miss Verinder joined me with a glass jug of cold water, which she had
taken from a side-table. "Let me pour out the water," she whispered. "I
must have a hand in it!"

I measured out the forty minims from the bottle, and poured the laudanum
into a medicine glass. "Fill it till it is three parts full," I said,
and handed the glass to Miss Verinder. I then directed Betteredge to
lock up the medicine chest; informing him that I had done with it now. A
look of unutterable relief overspread the old servant's countenance. He
had evidently suspected me of a medical design on his young lady!

After adding the water as I had directed, Miss Verinder seized a
moment--while Betteredge was locking the chest, and while Mr. Bruff was
looking back to his papers--and slyly kissed the rim of the medicine
glass. "When you give it to him," said the charming girl, "give it to
him on that side!"

I took the piece of crystal which was to represent the Diamond from my
pocket, and gave it to her.

"You must have a hand in this, too," I said. "You must put it where you
put the Moonstone last year."

She led the way to the Indian cabinet, and put the mock Diamond into the
drawer which the real Diamond had occupied on the birthday night. Mr.
Bruff wi