"Look here, Marvel. I'm not in the humour for any humbug. I want that box--now!"

"And I want that four hundred pounds before I produce the box--"

"Well, the money's ready."

"--and another five hundred when you touch the box--"

"You impudent swine!" cried Bullard viciously. "So that's your game!"

"Well, Mr. Bullard, when I came to think it over in that ghastly blizzard, I saw you had inadvertently underestimated the value of my services, and considering that I had already parted with those valuable papers of mine for one--"

"Oh, shut it, man! Do you take me for a fool?"

"On the contrary, Mr. Bullard! You want that box badly, and an extra five hundred is neither here nor there to you."

Bullard's expression was so ugly then that the pretender wavered. "Where is the Green Box? Answer!"

"Give me the four hundred, and I'll take you to it."

"Take me to it? I think not!"

"Oh, Mr. Bullard, surely you don't distrust me."

Bullard appeared to reflect, and said harshly: "One more chance. Bring the box here at ten to-morrow morning, and I'll give you two hundred extra, you dirty little thief!"

"Five hundred, Mr. Bullard," said Marvel gently. He could have hugged himself.

Again Bullard appeared to be lost in thought, his fingers toyed with the nugget on his chain. At last he said sullenly: "I might have known you would try it on, you scoundrel. But I must have the box first thing in the morning. It's awkward enough not to have it tonight." He turned to his desk and picked up an envelope with a typewritten address. He sat staring at it as though he had forgotten Marvel's presence.

Suddenly he wheeled and spoke. "You shall have five hundred in the morning--"

"And four hundred to-night, Mr. Bullard."

"Yes--an hour hence. Do you know the Victoria Docks?--Of course you do.

Well, the street named here"--he tapped the envelope--"is close to them.

Deliver this letter and bring me back an answer--and the four hundred are yours. Hold your tongue! The thing is too private for an ordinary messenger. It's entirely owing to your vile behaviour that this letter must be delivered to-night. Will you take it, or must I take it myself?

Mind, if I do, you can go to the devil for your four hundred, ay, and the five hundred to boot. I've stood the limit from you, Marvel, and I'm quite equal to locking you up in our strong-room here till you're ready and eager to give up the box for nothing!"

"Come, come, Mr. Bullard," said Marvel, rising, "there's no need for all this--this roughness. I'll take the letter with pleasure if you'll give me a couple of hundred to go on with."

Bullard tossed the letter back on the desk, and proceeded to light a cigar.

Marvel took a step forward. "I was only joking, Mr. Bullard. I'll take your message, and trust you."

"Very well," growled the other, handing it over. "Take care of it. You ought to be back in an hour. You'll find me here."

"Eight you are!" said Marvel, and went jauntily from the room.

Bullard sank back in his chair. "The blind fool!" he murmured, and grinned.

An hour later he was dining in the Savoy restaurant.

About ten o'clock he was shown into Lancaster's library. He was in evening dress. He carried a suit case bearing, in the midst of many old labels, his own initials. The moment the door was shut he said--

"Where's Mrs. Lancaster? Didn't she get my note?"

Lancaster, his weary eyes blinking in the sudden rousing from a troubled nap, replied: "Yes, it caught her as she was about to leave the house with Doris. Is anything the matter?"

"Did Doris go alone?"

"Yes, but--"

"I wish you would tell Mrs. Lancaster--"

At that moment the lady entered, gloriously attired, her eyes smouldering.

"What's the matter, Mr. Bullard?"

"Thanks for staying at home in response to my request," he said suavely.

"I have hopes that you won't find it a wasted evening. By the way, can you get rid of the attentions of your servants at so early an hour?"

Her sullen eyes brightened with curiosity. "I daresay I can, Mr. Bullard, but may I ask--"

"Please add the favour to the one already granted, and rejoin us here as soon as possible."

When she had gone, Bullard laid the suitcase on a chair, opened it, and took out the Green Box which he placed on the table. Then deliberately, and with a steady hand, he helped himself to a cigarette from his host's silver box, and lit it carefully.

"Well, Lancaster," he said, after exhaling a long whiff, "how's that?"

"Great Heavens!" Lancaster stopped staring and sat down feebly. "How did you get it? Where? Surely not in the same place as before!"

"That I can't tell you. The point that interests me is that it is here now. My story will keep--it's quite good enough for that. By the bye, where are your congratulations?"

Lancaster stretched out a shaking hand. "Take it away, for G.o.d's sake,"

he said. "Don't--don't let my wife see those stones. I tell you again, Bullard--I swear it--I don't want one more than will clear me of that one debt."

"Don't talk rot," was the light retort. "Mrs. Lancaster is going to choose one or two for luck. Between ourselves, as her prospective son-in-law I naturally desire to win her favour, as well as her entire confidence in my ability to provide suitably for her daughter. Besides, you must see that for your own sake it is better that she should be invol--pardon--interested. Why groan, my friend? Your troubles are over."

Mrs. Lancaster came in, gazed, and pounced. "What is it? What's wrong with Robert? What is all the mystery about?"

"This little box," said Bullard, patting it, "contains what I may call the Christopher Collection. No more questions now, if you please. Pray be seated. Are the servants--?"

"Yes, yes! Open it! I must see--"

"Unfortunately we lack the key. However, my expert tin-opener ought now to be waiting outside. I'll fetch him in, apologising for his uncouthness, which he can't help. He might like a little whisky, Lancaster. Ah, I see it is already provided. Better have some yourself, old man."

With these words, Bullard left the room to return a minute later with a rough-looking man in garb that might have been termed semi-sea-faring.

There was nothing particularly sinister about his reddish-bearded face, but his eyes were full of fears and suspicions, and the ordinary person would have shrunk from his contact. His conductor having locked the door, said--