"Is this true, Professor, at distances beyond which there are powder marks?" asked Jimmy.

"Yes, it is, but not within inches, of course, nor within a few feet, perhaps. But even at those distances it can often be approximated.

"Given the hypothesis that Miller was murdered, the rest was easy.

If you will go back there, Brasher, and dig your nail into the putty holding the window nearest to the bolt, you will find it soft; the other putty is hard. There are five rows of panes. The one I refer to is in the middle row at the extreme left. The killer had the forethought to use putty that was of about the same color as old putty. But I saw on the sill some minute grains of gla.s.s glinting in the light.

"Mrs. Horsnall, without knowing why I asked the question a.s.sured me that there had been no repairs, such as replacing panes of gla.s.s. When I leaned out of the window, I saw the scars in the cement. Perfectly obvious. An active man, a strong man, probably a left-handed man, threw a string with a stone at the end over Miller's Folly. With this string he drew over the building a stronger twine. Finally he drew over the top of the building a strong rope, like a wash line, or something stronger. He then drew both ends of the rope around, forming a loop, about the chimney.

"Using the chimney as his anchor, with his rope looped around it, it was fairly easy for an active man. He used the kind of spurs that electric workers use to climb up wooden poles. Those spurs left the scars I pointed out. He had a hand hold, of course, on the two ends of the rope hanging from the chimney about two feet from the window.

"The rest was rather difficult. When he reached the height of the window, the nearest pane, fortunately for him, the one near the bolt was two feet from his perch, at his left. That is why I suggest that he may be a left-handed man. He cut out the pane, opened the window, went in, killed Miller and then spent some time hiding his traces. Among these was replacing a pane of gla.s.s and using putty colored like old putty.

"A very, very dangerous murderer and a very clever one, but hardly a subtle one."

He turned to Brasher. "Now, young man, the rest ought to be simple police work. Find a man in possession of twine and rope, on which you will find adhering bits of brick, cement and paint, from Miller's roof. Find him in possession of a pair of spurs, on which you may find adhering bits of cement and you have your murderer."

As Brasher, thanking him effusively, was about to go. Professor Brierly detained him.

"Just a moment. I want to send a telegram to New York. Leave this at the telegraph office for me, please."

He turned to his companions as Brasher departed; he smiled whimsically:

"Since you insist on plunging me into these things, I might as well be prepared. I wired for several things that we may need before this is over."

McCall was knitting his brow. He had followed with glowing admiration the exposition of the old savant.

"Professor," he asked, "you say the murderer is a clever one, but hardly a subtle one. Why do you say that?"

Professor Brierly dropped wearily into a deep chair on the porch.

He shuffled the sheets of paper each with its bullet hole surrounded by powder marks.

"A man who kills another, usually uses the tools he knows best; frequently he uses the tools of his trade. That is easiest; following the lines of least resistance. Or, if killing becomes his profession, he adopts and adapts certain tools for his purpose, with which he becomes familiar.

"Just see how this murder was accomplished. A professional need not be ashamed of the way the pane of gla.s.s was inserted, the use of the rope, the climbing irons, or the spurs. The man who did this has used all these materials and tools before.

"Even in this country, where we are far behind certain European countries in such matters, it should be a simple matter for the police to pick up the killer. They can go through their records for the men who are accustomed to rob houses this way. They may find half a dozen in their files. They will pick up all of them who are not in prison and pin this murder on the guilty person.

The others will have adequate alibis.

"It must be obvious to you, of course, that though Miller's safe was rifled, robbery was not the real motive for the entrance; it was murder. It must also be obvious that no eighty-two-year-old man could have done this. If an eighty-two-year-old man engineered it, he hired some one. The man he hired, as I am showing you, left a broad trail. Find him and you will find the man behind him."

He rose. "I am rather tired. I am not as young as I was. I'd better take a rest."

"An eighty-two-year-old man? Are you suggesting, Professor--" began McCall.

"I? I am suggesting nothing. It was you, Mr. McCall, who made the ugly suggestion, remember.

"There is the mysterious number '14,' who, if he exists, is a.s.suredly not less than eighty-two years old. Then, there is a several million dollar fund of which you told me. It was you, Mr.

McCall, who made the ugly suggestion that such a sum was a tremendous temptation, both for men who have always been comparatively poor and for men who have had much and now have nothing.

"I am merely giving you the results of my conclusions from facts as I found them.

"Incidentally, this murderer, the man who killed Miller, is not very original. I remember a case in Germany in which a robber entered a house using just that means, a rope, a chimney and climbing irons. Yes, yes. It has all been done before. I did not need all the clues I found on the window and outside the house.

The powder marks were enough. The killer was too hasty or too careless or too ignorant. He might not have known that there is an enormous difference between powder marks inflicted when the muzzle is two inches away and those inflicted when the muzzle of the weapon is twelve inches away. The powder marks alone, without any other factors, that slight difference of a few inches, might make the difference between life and death for the murderer."

"And the two other men, Professor?" asked Jimmy.

"Of the two other men," snapped Professor Brierly, impatiently, "I know no more than you, and little is known about their deaths right now."

"But don't you think," continued the persistent reporter.

"You don't mean, don't I think, Mr. Hale," jeered Professor Brierly. "You mean don't I guess. No, I never guess. I leave that for highly imaginative newspaper men, or," he waved his hand sarcastically at his grinning a.s.sistant, "to John, there. Bring me some facts and I shall try to give you an opinion, an opinion that I may base on those facts, but, what do you know of the other men?" he challenged sharply.

"Well, there's not much question about one of them, the one who was drowned at Bradley Beach. That seems like an honest drowning.

But August Schurman, from our information, apparently hanged himself in his study in one of those old houses on the lower west side."

There was no sign of weariness now on the part of the old scientist. He was fully aroused. His deeply sunken eyes were glowing. Jimmy had used an old formula that he always found efficacious.

"Oh, yes?" Professor Brierly was leaning forward. "Not much question about Wrigley, the man who was found in the water at Bradley Beach, is there? All we know about him is that he was found dead in the water. Do you know that he was drowned? Of course you don't.

"And Schurman, the man who was reported to have committed suicide by hanging. All you know about that is that he was found hanging in his study, dead. Do you know that he died by hanging? Do you know that he was not dead before he was hung? If that is the case, then obviously, he could not have hung himself. Perfectly astonishing to me, Mr. Hale, that a man who has followed your profession as long as you have should be so gullible. For that matter, do you know those men are dead?"

After firing this sarcastic shaft, he shook his head, saying: "As I said, Mr. Hale, I am tired and I need some rest. And nothing makes me more tired than idle, futile speculation. The princ.i.p.al difference between a scientist and a newspaper man, Mr. Hale, is that one knows--the other--guesses."

The last rays of the sun were flaming in the sky across the lake when Professor Brierly suddenly said to Matthews: "John, take me down to the Higginbotham camp. The Judge tinkers with physics and mechanics, he offered me the use of his equipment. It may be a good thing for all of us to take our minds from this terrible affair. Too much brooding will certainly not help."

Matthews looked at him suspiciously. Without comment, he made ready to go.

Justice Higginbotham received the two men graciously. He took them at once to his work shop.

"I'm just an amateur, Professor. But it is a good thing for an old man to have a hobby, a very perplexing hobby. Modern science makes so many strides every year, every day, that it is practically impossible for an amateur to keep apace." He preceded them to a s.p.a.cious shed in the rear of the house. It was carefully and immaculately arranged, each article in its place and most of them carefully labeled.

Professor Brierly's eyes gleamed with interest as his eyes fell on a series of tubes, some of which resembled radio tubes in their sockets.

"Ah," he murmured. "Photo-electric tubes. It should be fairly easy for you to keep apace with that for the reason that this particular branch of science is still in its infancy and we are all groping in the dark. No matter how little you know about the matter, Judge, you cannot know a great deal less than any of us."

"That's your modesty, Professor. I had just been installing some of the simpler devices when," his fine features clouded, "this deplorable, this terrible affair interrupted me." There was silence for a moment. With a visible effort of the will, he continued:

"I am so glad you and Mr. Matthews are here. I am rather vague about it. While I enjoy finding things out for myself, this has been rather difficult. I am not certain I understand the photo-cell's sensitiveness to color. You see, I was trying--"

"Why, that is comparatively simple, Judge. I see you have everything needed right here."

"Yes, I got it all from a catalogue. But now that I have it, what am I going to do with it?"

Professor Brierly stepped forward. He and Matthews worked quickly, deftly, the old scientist uttering a word of explanation now and then. The venerable jurist watched their deft handling of intricate mechanism with keen interest and obvious enjoyment.

After half an hour that seemed to Justice Higginbotham only a few minutes, so keen had been his absorption in the task, Professor Brierly and Matthews stepped back. Professor Brierly had three cards colored red, green and blue in his hand. He pointed to three indicators that he had connected to wires running from a tube.