With this view I encouraged him to talk to me, contriving so to direct the conversation, on my side, as to lead him back again to the subject which had engaged us earlier in the evening,—the subject of the Diamond. I took care to revert to those portions of the story of the Moonstone which related to the transport of it from London to Yorkshire; to the risk which Mr. Blake had run in removing it from the bank at Frizinghall; and to the expected appearance of the Indians at the house on the evening of the birthday. And I purposely assumed, in referring to these events, to have misunderstood much of what Mr. Blake himself had told me a few hours since. In this way I set him talking on the subject with which it was now vitally important to fill his mind—without allowing him to suspect that I was making him talk for a purpose. Little by little he became so interested in putting me right that he forgot to fidget in the bed. His mind was far away from the question of the opium at the all-important time when his eyes first told me that the opium was beginning to lay its hold upon his brain.
I looked at my watch. It wanted five minutes to twelve when the premonitory symptoms of the working of the laudanum first showed themselves to me.
At this time no unpracticed eye would have detected any change in him. But as the minutes of the new morning wore away, the swiftly subtle progress of the influence began to show itself more plainly. The sublime intoxication of opium gleamed in his eyes; the dew of a steady perspiration began to glisten on his face. In five minutes more the talk which he still kept up with me failed in coherence. He held steadily to the subject of the Diamond; but he ceased to complete his sentences. A little later the sentences dropped to single words. Then there was an interval of silence. Then he sat up in bed. Then, still busy with the subject of the Diamond, he began to talk again—not to me but to himself. That change told me the first stage in the experiment was reached. The stimulant influence of the opium had got him.
The time now was twenty-three minutes past twelve. The next half-hour, at most, would decide the question of whether he would or would not get up from his bed and leave the room.
In the breathless interest of watching him—in the unutterable triumph of seeing the first result of the experiment declare itself in the manner, and nearly at the time, which I had anticipated—I had utterly forgotten the two companions of my night vigil. Looking toward them now, I saw the Law (as represented by Mr. Bruff's papers) lying unheeded on the floor. Mr. Bruff himself was looking eagerly through a crevice left in the imperfectly drawn curtains of the bed. And Betteredge, oblivious of all respect for social distinctions, was peeping over Mr. Bruff's shoulder.
They both started back on finding that I was looking at them, like two boys caught out by their schoolmaster in a fault. I signed to them to take off their boots quietly, as I was taking off mine. If Mr. Blake gave us the chance of following him, it was vitally necessary to follow him without noise.
Ten minutes passed—and nothing happened.
Then he suddenly threw the bedclothes off him. He put one leg out of bed. He waited.
"I wish I had never taken it out of the bank," he said to himself. "It was safe in the bank."
My heart throbbed fast; the pulses at my temples beat furiously. The doubt about the safety of the Diamond was once more the dominant impression in his brain! On that one pivot the whole success of the experiment turned. The prospect thus suddenly opened before me was too much for my shattered nerves. I was obliged to look away from him, or I should have lost my self-control.