“Must see who it is, I suppose,” he continued, “though one expects people to accept the hint of a closed oak.”

He strode across the room and flung open the door with an air of by no means gracious inquiry.

“It’s rather late for a business call,” said an apologetic voice outside, “but my client was anxious to see you without delay.”

“Come in, Mr. Lawley,” said Thorndyke, rather stiffly, and, as he held the door open, the two visitors entered.  They were both men—­one middle-aged, rather foxy in appearance and of a typically legal aspect, and the other a fine, handsome young fellow of very prepossessing exterior, though at present rather pale and wild-looking, and evidently in a state of profound agitation.

“I am afraid,” said the latter, with a glance at me and the dinner table, “that our visit—­for which I am alone responsible—­is a most unseasonable one.  If we are really inconveniencing you, Dr. Thorndyke, pray tell us, and my business must wait.”

Thorndyke had cast a keen and curious glance at the young man, and he now replied in a much more genial tone—­

“I take it that your business is of a kind that will not wait, and as to inconveniencing us, why, my friend and I are both doctors, and, as you are aware, no doctor expects to call any part of the twenty-four hours his own unreservedly.”

I had risen on the entrance of the two strangers, and now proposed to take a walk on the Embankment and return later, but the young man interrupted me.

“Pray don’t go away on my account,” he said.  “The facts that I am about to lay before Dr. Thorndyke will be known to all the world by this time to-morrow, so there is no occasion for any show of secrecy.”

“In that case,” said Thorndyke, “let us draw our chairs up to the fire and fall to business forthwith.  We had just finished our dinner and were waiting for the coffee, which I hear my man bringing down at this moment.”

We accordingly drew up our chairs, and when Polton had set the coffee on the table and retired, the lawyer plunged into the matter without preamble.

CHAPTER II

THE SUSPECT

“I had better,” said he, “give you a general outline of the case as it presents itself to the legal mind, and then my client, Mr. Reuben Hornby, can fill in the details if necessary, and answer any questions that you may wish to put to him.

“Mr. Reuben occupies a position of trust in the business of his uncle, John Hornby, who is a gold and silver refiner and dealer in precious metals generally.  There is a certain amount of outside assay work carried on in the establishment, but the main business consists in the testing and refining of samples of gold sent from certain mines in South Africa.

“About five years ago Mr. Reuben and his cousin Walter—­another nephew of John Hornby—­left school, and both were articled to their uncle, with the view to their ultimately becoming partners in the house; and they have remained with him ever since, occupying, as I have said, positions of considerable responsibility.