We talked generally on the events of the last fortnight; then I went more particularly into the circumstances attendant upon Fielding Thaneford's last hours, and Warriner listened attentively. The series of numbers which Betty had obtained from the dying man plainly appealed to his imagination, but he agreed with me that neither the numbers themselves nor their alphabetical equivalents offered any intelligible clue. "Of course he wanted to put over some message," he mused, "and he trusted to Betty's intuition to make things plain." * * * * * Betty, instead of Miss Graeme! Really, I hadn't been aware that Warriner was on so intimate a footing at the "Hundred." But of course it was all right; Warriner was older, by at least ten years, than either Betty or myself, and he probably looked on himself as a sort of elder brother to the entire household. I tried to recall if Betty was accustomed to call him by his Christian name. But I could not remember ... it was none of my business ... what difference anyway could it make. Unconsciously I had yielded to the slight pressure of Warriner's hand upon my arm. He led me away from the noisy gang of negroes working on the projected dam and power-house; presently we were within sight of one of the farm barns. The great double doors were open, but the distance was full half a mile, and nothing within the structure was discernible. Warriner unwrapped the slender parcel that he was carrying, and produced what looked very much like an old-fashioned spy glass, only of most unusual length. "And that's just what it is," he said, divining my thought. "Except that I have replaced the object glass with the lens I picked up the other day at Thaneford's crow's-nest on Sugar Loaf." "Go on." "I told you that there seemed to be some extraordinary optical properties in that piece of glass. I tried it out in my own laboratory, and got certain results. Then, when I was in Baltimore, I had Carter of Johns Hopkins check me up with his more complete apparatus. Some rather astonishing conclusions." "How so?" "Well, you've probably heard of the telephoto lens--a sort of long distance microscope, to use very colloquial language. I have seen telephoto pictures of the Matterhorn, taken five or six miles away, in which you could make out the actual geologic texture of the rocks. "But, of course, there must be plenty of light on the object to get clear definition. On the same principle, one can stand inside a room and see everything outdoors with perfect distinctness. It's a very different thing, trying to look into a room from without. The visibility is low, as they say, and you don't get much." "Yes, I understand that." "Again there are optical lenses specially designed to make the most of poor illumination. A familiar example is the sailor's night-glass.