Detective Kennedy's Cases. Arthur B. Reeve
Back of, or in front of the Carter house, according as you fancied it faced the bay or not, was the boathouse, built by Carter's father, who had been a great yachtsman in his day and commodore of the club. His son had not gone in much for water sports and had converted the corner underneath a sort of observation tower into a sort of country law office.
"There has always seemed to me to be something strange about that boathouse since the old man died," remarked McNeill in a half whisper as we left Carter. "He always keeps it locked and never lets anyone go in there, although they say he has it fitted beautifully with hundreds of volumes of law books, too."
Kennedy had been climbing the hill back of the house and now paused to look about. Below was the Carter garage.
"By the way," exclaimed McNeill, as if he had at last hit on a great discovery, "Carter has a new chauffeur, a fellow named Wickham. I just saw him driving down to the village. He's a chap that it might pay us to watch--a newcomer, smart as a steel trap, they say, but not much of a talker." "Suppose you take that job-- watch him," encouraged Kennedy. "We can't know too much about strangers here, McNeill."
"That's right," agreed the detective. "I'll follow him back to the village and get a line on him."
"Don't be easily discouraged," added Kennedy, as McNeill started down the hill to the garage. "If he is a fox he'll try to throw you off the trail. Hang on."
"What was that for?" I asked as the detective disappeared. "Did you want to get rid of him?"
"Partly," replied Craig, descending slowly, after a long survey of the surrounding country.
We had reached the garage, deserted now except for our own car.
"I'd like to investigate that tower," remarked Kennedy with a keen look at me, "if it could be done without seeming to violate Mr. Carter's hospitality."
"Well," I observed, my eye catching a ladder beside the garage, "there's a ladder. We can do no more than try."
He walked over to the automobile, took a little package out, slipped it into his pocket, and a few minutes later we had set the ladder up against the side of the boathouse farthest away from the house. It was the work of only a moment for Kennedy to scale it and prowl across the roof to the tower, while I stood guard at the foot.
"No one has been up there recently," he panted breathlessly as he rejoined me. "There isn't a sign."
We took the ladder quietly back to the garage, then Kennedy led the way down the shore to a sort of little summerhouse cut off from the boathouse and garage by the trees, though over the top of a hedge one could still see the boathouse tower.
We sat down, and Craig filled his lungs with the good salt air, sweeping his eye about the blue and green panorama as though this were a holiday and not a mystery case.
"Walter," he said at length, "I wish you'd take the car and go around to Verplanck's. I don't think you can see the tower through the trees, but I should like to be sure."
I found that it could not be seen, though I tried all over the place and got myself disliked by the gardener and suspected by a watchman with a dog.
It could not have been from the tower of the boathouse that we had seen the light, and I hurried back to Craig to tell him so. But when I returned, I found that he was impatiently pacing the little rustic summerhouse, no longer interested in what he had sent me to find out.
"What has happened?" I asked eagerly.
"Just come out here and I'll show you something," he replied, leaving the summerhouse and approaching the boathouse from the other side of the hedge, on the beach, so that the house itself cut us off from observation from Carter's.
"I fixed a lens on the top of that tower when I was up there," he explained, pointing up at it. "It must be about fifty feet high. From there, you see, it throws a reflection down to this mirror. I did it because through a skylight in the tower I could read whatever was written by anyone sitting at Carter's desk in the corner under it."
"Read?" I repeated, mystified.
"Yes, by invisible light," he continued. "This invisible light business, you know, is pretty well understood by this time. I was only repeating what was suggested once by Professor Wood of Johns Hopkins. Practically all sources of light, you understand, give out more or less ultraviolet light, which plays no part in vision whatever. The human eye is sensitive to but few of the light rays that reach it, and if our eyes were constituted just the least bit differently we should have an entirely different set of images.
"But by the use of various devices we can, as it were, translate these ultraviolet rays into terms of what the human eye can see. In order to do it, all the visible light rays which show us the thing as we see it--the tree green, the sky blue--must be cut off. So in taking an ultraviolet photograph a screen must be used which will be opaque to these visible rays and yet will let the ultraviolet rays through to form the image. That gave Professor Wood a lot of trouble. Glass won't do, for glass cuts off the ultraviolet rays entirely. Quartz is a very good medium, but it does not cut off all the visible light. In fact there is only one thing that will do the work, and that is metallic silver."
I could not fathom what he was driving at, but the fascination of Kennedy himself was quite sufficient.
"Silver," he went on, "is all right if the objects can be illuminated by an electric spark or some other source rich in the rays. But it isn't entirely satisfactory when sunlight is concerned, for various reasons that I need not bore you with. Professor Wood has worked out a process of depositing nickel on glass. That's it up there," he concluded, wheeling a lower reflector about until it caught the image of the afternoon sun thrown from the lens on the top of the tower.
"You see," he resumed, "that upper lens is concave so that it enlarges tremendously. I can do some wonderful tricks with that."
I had been lighting a cigarette and held a box of safety wind matches in my hand.
"Give me that matchbox," he asked.
He placed it at the foot of the tower. Then he went off, I should say, without exaggeration, a hundred feet.
The lettering on the matchbox could be seen in the silvered mirror, enlarged to such a point that the letters were plainly visible!
"Think of the possibilities in that," he added excitedly. "I saw them at once. You can read what some one is writing at a desk a hundred, perhaps two hundred feet away."
"Yes," I cried, more interested in the practical aspects of it than in the mechanics and optics. "What have you found?"
"Some one came into the boathouse while you were away," he said. "He had a note. It read, 'Those new detectives are watching everything. We must have the evidence. You must get those letters to-night, without fail.'"
"Letters--evidence," I repeated. "Who wrote it? Who received it?"
"I couldn't see over the hedge who had entered the boathouse, and by the time I got around here he was gone."
"Was it Wickham--or intended for Wickham?" I asked.
Kennedy shrugged his shoulders.
"We'll gain nothing by staying here," he said. "There is just one possibility in the case, and I can guard against that only by returning to Verplanck's and getting some of that stuff I brought up here with me. Let us go."
Late in the afternoon though it was, after our return, Kennedy insisted on hurrying from Verplanck's to the Yacht Club up the bay. It was a large building, extending out into the water on made land, from which ran a long, substantial dock. He had stopped long enough only to ask Verplanck to lend him the services of his best mechanician, a Frenchman named Armand.
On the end of the yacht club dock Kennedy and Armand set up a large affair which looked like a mortar. I watched curiously, dividing my attention between them and the splendid view of the harbor which the end of the dock commanded on all sides.
"What is this?" I asked finally. "Fireworks?"
"A rocket mortar