that I hoped to pick up. But there were other matters. I knew that there was a man, in some way connected with the robbery, who had a short, fair moustache. I had to find out who he was. Also if there was any source from which some other person might collect specimen hairs from that moustache—a hair-brush, for instance—and if such source existed, who had access to it.
“Then there was the personality of the thief. One knew a good deal about him by this time. He was an ingenious man; a fairly good workman, at any rate, with metal-worker’s tools, but not a skilled jeweller. He must have been able to make a key from a wax squeeze—unless he were Woodstock himself, which he pretty certainly was not; for none of the others had sufficiently free access to the strong-room to do what had been done. Then he must have had at least a simple working knowledge of electric batteries, since we could be fairly certain that he made the electrotypes himself; he would never have run the risk of putting the forgery out to the trade. He was clearly a secretive, self-contained man. The only fallacy that I had to guard against was the possibility of a confederate outside the office, who might have done the actual work; but this possibility seemed to be negatived by the whole character of the robbery and especially by one very odd feature in it, which was this: Professor Eccles had noticed with surprise that many of the stones which were taken were of quite trifling intrinsic value, so trifling that, if they had been sold, they would hardly have realized enough to pay the cost of replacing them with the specially-made counterfeits. Indeed, in one case, at least, the thief must have lost money on the transaction, for he had taken a fine moonstone and replaced it with an inferior one of the same dimensions. But the value of the original was only about ten shillings, and he must have spent more than that on the replacement. The professor was greatly puzzled by this, having assumed, of course, that the gems were stolen to sell. But to me, this rather anomalous feature of the robbery offered a very curious suggestion; which was that no sale of the booty had ever been contemplated. It looked like a collector’s robbery; and if there had been a collector in any way connected with the parties, I should have given him my very close attention. But, so far as I knew, there was none. Nevertheless, this peculiarity of the robbery had to be borne in mind when I came to make my investigations on the spot.
“Let me now briefly describe those investigations. Their main object was to ascertain whether there were any traces of wood-dust in the premises of either Hollis or Woodstock, and the method was this: in each case, a rough ground-plan of the premises was made; then small areas of the floors were cleaned thoroughly with a specially constructed vacuum cleaner and the dust from each area put into an envelope marked with a number, which number was also marked in the plan on the spot from which the dust had been collected. The collection was carried out by my laboratory assistant, Mr. Polton, whom you have seen, leaving me free to make inquiries and to inspect the premises. Of course, the samples of dust had to be brought home to be examined in the laboratory, so we were hampered by the circumstance that we did not know at the time whether any wood-dust had or had not been obtained. But this proved to be of no importance.
“We operated first at Mr. Hollis’s house, regardless of his scornful protests. Then we went on to Mr. Woodstock’s office; and there I had a rather remarkable experiences As I entered with Mr. Woodstock, I saw an elderly man engaged in repairing an electric bell; and a glance at his hands and the way in which he manipulated his tools showed the unmistakable facility and handiness of the skilled workman. It was a little startling; for here were two of the characteristics of the unknown person I was endeavouring to identify. This man had evident skill in the use of metal-worker’s tools and he clearly knew a good deal about electric batteries. And when I learned that this Mr. Wampole was the office-keeper and that he evidently had a key of the premises, I was still further impressed. I began to revise my opinion as to there being no confederate; for the fact remained that Osmond had absconded and that his disappearance—until it was otherwise explained—undeniably connected him with the robbery. I began to think it possible that there had been a partnership and that he had been used as a cat’s paw. Meanwhile, I had to find out as much as I could about him, and to this end I sat down by Wampole, as he worked at refitting the batteries, and questioned him on the subject of Osmond’s appearance, habits, temperament, and circumstances. It is only fair to him to say that he scouted the idea of Osmond’s having committed the robbery and gave excellent reasons for rejecting it. On the other hand, his description of Osmond made it clear that the hairs which I had found in the boxes were Osmond’s hairs; and when I expressed a wish to inspect Osmond’s desk, he took me to it readily enough, and as it was unlocked, he threw up the lid and showed me the interior. The most interesting thing in it, from my point of view, was a pair of hair-brushes; from which I was able to extract several moustache hairs which appeared—and subsequently turned out to be—identically similar to those found in the boxes.
“The examination of Osmond’s desk suggested a similar examination of all the other desks in the office, finishing up with that belonging to Mr. Wampole. And it was in examining that desk that I did really receive somewhat of a shock. For when we came to turn out its contents, I found that these included, in addition to a number of metal-worker’s tools, a work man’s linen apron and some battery terminals and insulated wire, a stamp-album, a tray of military buttons and badges and old civilian buttons, and another tray of old coins.
“The coincidence was too striking to be ignored. Here was a man who had free access to these premises night and day, and who corresponded in every particular with the unknown robber. We had already seen that he had the skill and special knowledge that were postulated; now this stamp-album, these buttons, badges, and coins, wrote him down an inveterate collector. If I had looked on Mr. Wampole with interest before, I now regarded him with very definite suspicion. Whatever significance the hairs had seemed to have was now entirely against him; for there were the brushes, easily available, and he knew it.
“I must confess that I was greatly puzzled. Every new fact that I observed seemed more and more to confuse the issues. With the exception of the hairs—which were, at least, doubtful evidence—I had found nothing whatever to incriminate Osmond; whereas Wampole presented a highly suspicious appearance. But Osmond had absconded; which seemed to put Wampole outside the inquiry, excepting as a confederate. And when I went with Wampole to Osmond’s rooms, my inspection of them only left me more puzzled; for the personality that they reflected was the very opposite of that indicated by the nature and method of the robbery. Instead of the avarice and cunning that characterized the robber, the qualities suggested were those of a hardy, adventurous, open-air man, simple to austerity in his tastes and concerned with any thing rather than wealth and worldly possessions. The very photographs on the mantelpiece proclaimed the incongruity, especially that of his mother, whom Wampole informed me he strongly resembled; which showed the face of a dignified, strong, resolute, courageous looking lady, whose son I found it hard to picture, first as a thief, and then as a panicky fugitive. Yet the fact remained that Osmond had absconded.
“However, when we got home and proceeded to question the samples of dust in the laboratory, they gave an answer that was unmistakable. The results were roughly thus: the samples from Hollis’s house contained no wood-dust; those from Osmond’s rooms contained none; that from the inside of his desk contained none and that from his office floor barely a trace. Those from the floor of the clerks’ office yielded a very small quantity, but that from the floor by Wampole’s desk contained quite a large amount, while the dust extracted from the interior of his desk was full of the castings—derived, no doubt, to a large extent from the apron which he had kept in it. So the murder was out. The man who had packed those boxes was Mr. Wampole, and the hairs which I found in them had come from Osmond’s brushes.
“One thing only remained to be done: the final verification. The wood-dust had to be traced to its ultimate source in Wampole’s lair. This invaluable service was carried out by my assistant, Polton, who, with extraordinary tact and skill, contrived to get a glimpse into the workshop during Wampole’s absence; and when he peeped in, the first object that met his eye was a sparrowhawk, planted in a little log of cherry-wood that was absolutely riddled by the worm. That concluded the inquiry so far as I was concerned, though some further work had to be done to enable the police to act. But no doubt Mr. Penfield has told you about the lapidary and the police raid which resulted in Wampole’s death and the discovery of the gems in his possession.”
“Yes,” Osmond