“I have not yet seen the interior of the box, Mr. Smith,” he said.

Smith paused in his perambulation of the carpet and stared hard at the celebrated art dealer.

“Unfortunately,” he replied, “the key is missing.”

“Ah!” cried the assistant, Lewison, excitedly, “you are mistaken, sir!  Coffers of this description and workmanship are nearly always complicated conjuring tricks; they rarely open by any such rational means as lock and key.  For instance, the Kuren treasure-chest to which I referred, opens by an intricate process involving the pressing of certain knobs in the design, and the turning of others.”

“It was ultimately opened,” said Mr. Meyerstein, with a faint note of professional envy in his voice, “by one of Christie’s experts.”

“Does my memory mislead me,” I interrupted, “or was it not regarding the possession of the chest to which you refer, that the celebrated case of ‘Hague versus Jacobs’ arose?”

“You are quite right, Dr. Petrie,” said Meyerstein, turning to me.  “The original owner, a member of the Younghusband Expedition, had been unable to open the chest.  When opened at Christie’s it proved to contain jewels and other valuables.  It was a curious case, wasn’t it, Lewison?” turning to his clerk.

“Very,” agreed the other absently; then—­“Have you endeavored to open this box, Mr. Smith?”

Nayland Smith shook his head grimly.

“From its weight,” said Meyerstein, “I am inclined to think that the contents might prove of interest.  With your permission I will endeavor to open it.”

Nayland Smith, tugging reflectively at the lobe of his left ear, stood looking at the expert.  Then—­

“I do not care to attempt it at present,” he said.

Meyerstein and his clerk stared at the speaker in surprise.

“But you would be mad,” cried the former, “if you accepted an offer for the box, whilst ignorant of the nature of its contents.”

“But I have invited no offer,” said Smith.  “I do not propose to sell.”

Meyerstein adjusted his pince-nez again.

“I am a business man,” he said, “and I will make a business proposal:  A hundred guineas for the box, cash down, and our commission to be ten per cent on the proceeds of the contents.  You must remember,” raising a fat forefinger to check Smith, who was about to interrupt him, “that it may be necessary to force the box in order to open it, thereby decreasing its market value and making it a bad bargain at a hundred guineas.”

Nayland Smith met my gaze across the room; again a slight smile crossed the lean, tanned face.

“I can only reply, Mr. Meyerstein,” he said, “in this way:  if I desire to place the box on the market, you shall have first refusal, and the same applies to the contents, if any.  For the moment if you will send me a note of your fee, I shall be obliged.”  He raised his hand with a conclusive gesture.  “I am not prepared to discuss the question of sale any further at present, Mr. Meyerstein.”