But things came to a head enough. It was at my home, after they had taken their degrees and dropped out of the world’s sight, that the beginning of the end came to pass. Both were men of means, with little inclination and no necessity for professional life. My friendship and their mutual animosity were the two things that linked them in any way together. While they were very often at my place, they made it a fastidious point to avoid each other on such visits, though it was inevitable, under the circumstances, that they should come upon each other occasionally. On the day I have in recollection, Paul Tichlorne had been mooning all morning in my study over a current scientific review. This left me free to my own affairs, and I was out among my roses when Lloyd Inwood arrived. Clipping and pruning and tacking the climbers on the porch, with my mouth full of nails, and Lloyd following me about and lending a hand now and again, we fell to discussing the mythical race of invisible people, that strange and vagrant people the traditions of which have come down to us. Lloyd warmed to the talk in his nervous, jerky fashion, and was soon interrogating the physical properties and possibilities of invisibility. A perfectly black object, he contended, would elude and defy the acutest vision. “Color is a sensation,” he was saying. “It has no objective reality. Without light, we can see neither colors nor objects themselves. All objects are black in the dark, and in the dark it is impossible to see them. If no light strikes upon them, then no light is flung back from them to the eye, and so we have no vision-evidence of their being.” “But we see black objects in daylight,” I objected. “Very true,” he went on warmly. “And that is because they are not perfectly black. Were they perfectly black, absolutely black, as it were, we could not see them—ay, not in the blaze of a thousand suns could we see them! And so I say, with the right pigments, properly compounded, an absolutely black paint could be produced which would render invisible whatever it was applied to.” “It would be a remarkable discovery,” I said non-committally, for the whole thing seemed too fantastic for aught but speculative purposes. “Remarkable!” Lloyd slapped me on the shoulder. “I should say so. Why, old chap, to coat myself with such a paint would be to put the world at my feet. The secrets of kings and courts would be mine, the machinations of diplomats and politicians, the play of stock-gamblers, the plans of trusts and corporations. I could keep my hand on the inner pulse of things and become the greatest power in the world. And I—” He broke off shortly, then added, “Well, I have begun my experiments, and I don’t mind telling you that I’m right in line for it.” A laugh from the doorway startled us. Paul Tichlorne was standing there, a smile of mockery on his lips. “You forget, my dear Lloyd,” he said. “Forget what?” “You forget,” Paul went on—“ah, you forget the shadow.”