"You guess what I'm coming to. This particular lens has the telephoto range, and, at the same time, it works with the minimum of illumination. Never saw anything like it before, and it would be worth a fortune in the binocular field." "Show me." Chalmers Warriner rested the long glass on a fence post, ranged it on the open door of the barn nearly three thousand yards away, and did some preliminary focussing and other adjustments. He took a look, and then invited me to do the same. It was truly marvellous! It seemed as though I were standing on the very threshold of the barn and looking inside. I recognized Adam Lake, the field foreman, working on the engine of a small tractor. In the background, Zack was oiling a set of harness. The details were astoundingly distinct. "It's evident now," continued Warriner, "that the iron trough at Thaneford's observation point was intended to support a telescope such as this. The instrument is too long to hold steadily in the hand, and it had to be ranged precisely on the two-foot opening of the pridella. It was therefore possible to sit comfortably concealed on Sugar Loaf, and keep accurate tab on whatever was passing in Francis Graeme's library; provided, of course, that one of the pridellas was open. Even this wonderful lens could not penetrate stained glass. It isn't an X-ray apparatus." "Granting all your premises--why?" "And that's just what I would like mightily to know," answered Warriner. "But let's go back to the house; there's something else I want to show you." We went to the library, and, by way of refreshment after our long walk in the sun, I told Effingham to make us some claret cup. Presently he brought it in, and proceeded to fill a couple of long, Rhinewine glasses with the beverage. The big cut-glass pitcher was heavily beaded with cool moisture, and looked irresistibly inviting; the Eighteenth Amendment was unanimously declared unconstitutional, and we drank and drank again. So long as the cellar of "Hildebrand Hundred" continued to function it was still worth while to acquire a thirst. Warriner took a small object from a cardboard box, and passed it over to me. "Remember that?" he asked. "I suppose it's the same moth cocoon which we found plastered on the postern-door----" "And directly on the line between door and casing," interjected Warriner. "Being proof positive that the door could not have been opened for a period considerably antecedent to Graeme's death." "I presume so." "Well, I took that cocoon home, and made some tests. It had been fastened on the door by means of mucilage--common, ordinary mucilage." I stared at Warriner without speaking. This was indeed confounding.