needs something to explain the total. But, God bless us! what is this?”
“This” was, in effect, a diminutive vacuum cleaner, fitted with a little revolving brush and driven by means of a large dry battery, which Polton was at the moment disinterring from his suitcase. Thorndyke briefly explained the nature of the apparatus while Mr. Wampole stared at it with an expression of stupe faction.
“But why have you brought it here, sir?” he exclaimed. “The premises would certainly be the better for a thorough cleaning, but surely—”
“Oh, we are not going to ‘vacuum clean’ you,” Thorndyke reassured him. “We are going to take samples of dust from the different parts of the premises.”
“Are you, indeed, sir? And, if I may take the liberty of asking, what do you propose to do with them?”
“I shall examine them carefully when I get home,” Thorndyke replied, “and I may then possibly be able to judge whether the robbery took place here or elsewhere.”
As Thorndyke furnished this explanation, Mr. Wampole stood gazing at him as if petrified. Once he opened his mouth, but shut it again tightly as if not trusting himself to speak. At length he rejoined: “Wonderful! wonderful!” and then, after an interval, he continued meditatively: “I seem to have read somewhere of a wise woman of the East who was able, by merely examining a hair from the beard of a man who had fallen downstairs, to tell exactly how many stairs he had fallen down. But I never imagined that it was actually possible.”
“It does sound incredible,” Thorndyke admitted, gravely. “She must have had remarkable powers of deduction. And now, if Mr. Polton is ready, we will begin our perambulation. Which was Mr. Osmond’s office?”
“I will show you,” replied Mr. Wampole, recovering from his trance of astonishment. He led the way out into the hall and thence into a smallish room in which were a writing-table and a large, old-fashioned, flap-top desk.
“This table,” he explained, “is Mr. Hepburn’s. The desk was used by Mr. Osmond and his belongings are still in it. That second door opens into Mr. Woodstock’s office.”
“Is it usually kept open or closed?” Thorndyke asked.
“It is nearly always open; and as it is, as you see”—here he threw it open—“exactly opposite the door of the strong-room, no one could go in there unobserved unless Mr. Woodstock, Mr. Hepburn, and Mr. Osmond had all been out at the same time.”
Thorndyke made a note of this statement and then asked: “Would it be permissible to look inside Mr. Osmond’s desk? Or is it locked?”
“I don’t think it is locked. No, it is not,” he added, demonstrating the fact by raising the lid; “and, as you see, there is nothing very secret inside.”
The contents, in fact, consisted of a tobacco-tin, a couple of briar pipes, a ball of string, a pair of gloves, a clothes-brush, a pair of much-worn hair-brushes, and a number of loose letters and bills. These last Thorndyke gathered together and laid aside without examination, and then proceeded methodically to inspect each of the other objects in turn, while Mr. Wampole watched him with the faintest shadow of a smile.
“He seems to have had a pretty good set of teeth and a fairly strong jaw,” Thorndyke remarked, balancing a massive pipe in his fingers and glancing at the deep tooth-marks on the mouth-piece, “which supports your statement as to his physique.”
He peered into the tobacco-tin, smelt the tobacco, inspected the gloves closely, especially at their palmar surfaces, and tried them on; examined the clothes brush, first with the naked eye and then with the aid of his pocket-lens, and, holding it inside the desk, stroked its hair backwards and forwards, looking closely to see if any dust fell from it. Finally, he took up the hair-brushes one at a time and, having examined them in the same minute fashion, produced from his pocket a pair of fine forceps and a seed-envelope. With the forceps he daintily picked out from the brushes a number of hairs which he laid on a sheet of paper, eventually transferring the collection to the little envelope, on which he wrote: “Hairs from John Osmond’s hair-brushes.”
“You don’t take anything for granted, sir,” remarked Mr. Wampole, who had been watching this proceeding with concentrated interest (perhaps he was again reminded of the wise woman of the East).
“No,” Thorndyke agreed. “Your description was hearsay testimony, whereas these hairs could be produced in Court and sworn to by me.”
“So they could, sir; though, as it is not disputed that Mr. Osmond has been in this office, I don’t quite see what they could prove.”
“Neither do I,” rejoined Thorndyke. “I was merely laying down the principle.”
Meanwhile, Polton had been silently carrying out his part of the programme, not unobserved by Mr. Wampole; and a pale patch about a foot square, between Mr. Hepburn’s chair and the front of the table, where the pattern of the grimy carpet had miraculously reappeared, marked the site of his operations. Tenderly removing the little silken bag, now bulging with its load of dust, he slipped it into a numbered envelope and wrote the number on the spot on the plan to which it corresponded.
Presently a similar patch appeared on the carpet in front of Osmond’s desk, and when the sample had been disposed of and the spot on the plan marked, Polton cast a wistful glance at the open desk.
“Wouldn’t it be as well, sir, to take a specimen from the inside?” he asked.
“Perhaps it would,” Thorndyke replied. “It should give us what we may call a ‘pure culture.’” He rapidly emptied the desk of its contents, when Polton introduced the nozzle of his apparatus and drew it slowly over every part of the interior. When this operation was completed, including the disposal of the specimen and the marking of the plan, the party moved into Mr. Woodstock’s office, and from thence back into the clerks’ office.
“I find this investigation intensely interesting,” said Mr. Wampole, rubbing his hands gleefully. “It seems to combine the attractions of a religious ceremony and a parlour game. I am enjoying it exceedingly. You will like to have the names of the clerks who sit at those desks, I presume.”
“If you please,” replied Thorndyke.
“And, of course, you will wish to take samples from the insides of the desks. You certainly ought to. The informal lunches which the occupants consume during the forenoon will have left traces which should be most illuminating. And the desks are not locked, as there are no keys.”
Mr. Wampole’s advice produced on Polton’s countenance a smile of most extraordinary crinkliness, but Thorndyke accepted it with unmoved gravity and it was duly acted upon. Each of the desks was opened and emptied of its contents—instructive enough as to the character and personal habits of the tenant—and cleared of its accumulation of crumbs, tobacco-ash, and miscellaneous dirt, the ‘catch’ forming a specimen supplementary to those obtained from the floor. At length, when they had made the round of the office, leaving in their wake a succession of clean squares on the matting which covered the floor, Mr. Wampole halted before an old-fashioned high desk which stood in a corner in company with a high office-stool.
“This is my desk,” said he. “I presume that you are going to take a little souvenir from it?”
“Well,” replied Thorndyke, “we may as well complete the series. We operated on Mr. Hollis’s premises this morning.”
“Did you indeed, sir! You went there first; and very proper too. I am sure Mr. Hollis was very gratified.”
“If he was,” Thorndyke replied with a smile, “he didn’t make it obtrusively apparent. May I compliment you on your desk? You keep it in apple-pie order.”
“I try to show the juniors an example,” replied Mr. Wampole, throwing back the lid of the desk and looking complacently at the neatly stowed contents. “It is a miscellaneous collection,” he added as he proceeded to transfer his treasures from the desk to a cleared space on the table.
It