"A bird 'ops," pontificated Mr. Collop, significantly. "'E don't run--'cept ostriches and such like. 'E 'ops. Foller me!" His left hand slightly clenched, with his right he pointed down continuously to the border of the snow, whence, at short intervals, those two triple marks appeared and reappeared. "Mark you," said Mr. Collop, facing the group--the now half-frozen group. "I said, a bird 'ops. What 'opped 'ere? A bird!" They approached the fatal tree. "And 'ere," said Mr. Collop in the tone of a guide conducting a party of tourists, "our marks are lost. And for why? 'E takes the air! Whither will 'e take the air? Put ye'self in his place. Whither would a bird take the air from hence, seeing what fatal burden 'e bore in 'is beak?" He half waved, half pointed, with his left hand at the hollow-branched stump just higher than their heads and some ten feet away. "Foller me," he said again. They followed him--but not to the point of going on the snow, which Mr. Collop did with great courage and resolution. He stood on tiptoe by the trunk and stretched his clenched left hand upward, groped with it hidden to the wrist in the hollow of the rotten branch, lifted it out again high between them and the frosty January sky. There held between the thumb and forefinger, unmistakable, recovered, was the Emerald. "What did I tell yer?" he waved triumphantly in that keen air, "Brains, gentlemen ... ladies _and_ gentlemen, I mean.... Brains! Induction." And he calmly slipped the gem into his pocket. Had they been in a warm room they would have applauded: it was so exactly like the best tricks. But they were cold. They huddled back. It was only twenty or thirty yards; they would be in the warmth again in a moment. I know very well that there ought to have been a shock of surprise. A cheer. Excitement. What you will. But, Lord! it was so cold! One by one they clambered, straddled, strode, vaulted, crawled and shambled over the low window ledge and back into the room. Mr. Collop came last, and slammed the window down behind him: and Aunt Amelia welcomed them as might the old nurse of Ulysses when he returned at last from so much wandering. As the warm air revived them they began to feel him, very rightly, a hero. "Now," said he, "shall I show ye all 'ow these things are done? Step by step, unbeknownst to others? Ah! It's worth knowing! Look 'ere," and he began, their interest rising as their blood began to move again: "You mayn't see it, but I see it, here on this parky floor." He stooped down and tapped it with his finger. "Little marks. Little marks." There were no little marks--but no matter. He had done his best to suggest them. The Professor greatly helped them by his folly. "Yes! I see! Oh! Yes! Most interesting! I see them now!"