"Three years of cultivation," he declared, "and I can win them back to edibility. Five, and they'll be almost where they were before the great catastrophe. As for the fruits, the apple, cherry, and pear, all they need is care and scientific grafting. "I predict that ten years from to-day, orchards and cornfields and gardens shall surround this bungalow, and the heritage of man shall be brought back to this old world!" "Always giving due credit to the encyclopedia," added Beatrice. "And to _you!_" he laughed happily. "This is all on your account, anyhow. If I were alone in the world, you bet there'd be no gardens made!" "No, I don't believe there would," she agreed, a serious look on her face. "But, then," she concluded, smiling again, "you aren't alone, Allan. You've got _me!_" He tried to catch her in his arms, but she evaded him and ran back toward the bungalow. "No, no, you've got to work," she called to him from the porch. "And so have I. Good-by!" And with a wave of the hand, a strong, brown hand now, slim and very beautiful, she vanished. Stern stood in thought a moment, then shook his head, and, with a singular expression, picked up his hoe, and once more fell to cultivating his precious little garden-patch, on which so infinitely much depended. But something lay upon his mind; he paused, reflecting; then picked up a stone and weighed it in his hand, tried another, and a third. "I'm damned," he remarked, "if these feel right to met I've been wondering about it for a week now--there's got to be some answer to it. A stone of this size in the old days would certainly have weighed more. And that big boulder I rooted out from the middle of the field--in the other days I couldn't have more than stirred it. "Am I so very much stronger? So much as all that? Or have things grown lighter? Is that why I can leap farther, walk better, run faster? What's it all about, anyhow?" He could not work, but sat down on a rock to ponder. Numerous phenomena occurred to him, as they had while he had lain wounded under the tree by the river during their first few days at the bungalow. "My observations certainly show a day only twenty-two hours and fifty-seven minutes long; that's certain," he mused. "So the earth is undoubtedly smaller. But what's that got to do with the mass of the earth? With weight? Hanged if I can make it out at all! "Even though the earth has shrunk, it ought to have the same power of gravitation. If all the molecules and atoms really were pressed together, with no space between, probably the earth wouldn't be much bigger than a football, but it would weigh just that much, and a body would fall toward it from space just as fast as now. Quite a hefty football, eh? For the life of me I can't see why the earth's having shrunk has affected the weight of everything!" Perplexed, he went back to his work again. And though he tried to banish the puzzle from his mind it still continued to haunt and to annoy him.