He clapped me on the shoulder. "You're dead right, John--it did, and I don't believe any of us would have thought to mention it." He looked at me admiringly. "Behold the power of a naturally strong mind--in spite of circumstances! Yes, really that's a fact. You see few people are able to visualize what they have not seen. Most of us had no more idea of the surface of the earth than an ant has of a meadow. In each mind was only a thready fragment of an idea of the world--no real geographic view. And when we got flying all over it commonly, it became real and familiar to us--like a big garden. "I guess that helped on the tree idea. You see, in our earlier kind of agriculture the first thing we did was to cut down the forest, dig up and burn over, plow, harrow, and brush fine--to plant our little grasses. All that dry, soft, naked soil was helplessly exposed to the rain--and the rain washed it steadily away. In one heavy storm soil that it had taken centuries of forest growth to make would be carried off to clog the rivers and harbors. This struck us all at once as wasteful. We began to realize that food could grow on trees as well as grasses; that the cubic space occupied by a chestnut tree could produce more bushels of nutriment than the linear space below it. Of course we have our wheat fields yet, but around every exposed flat acreage is a broad belt of turf and trees; every river and brook is broadly bordered with turf and trees, or shrubs. We have stopped soil waste to a very great extent. Also we make soil--but that is a different matter." "Hurrying Mother Nature again, eh?" "Yes, the advance in scientific agriculture is steady. Don't you remember that German professor who raised all kinds of things in water? Just fed them a pinch of chemicals now and then? They said he had a row of trees before his door with their roots in barrels of water--the third generation that had never touched ground. We kept on studying, and began to learn how to put together the proper kind of soil for different kinds of plants. Rock-crushers furnished the basis, then add the preferred constituents and sell, by the bag or the ship load. You can have a radish bed in a box on your window sill, if you like radishes, that will raise you the fattest, sweetest, juiciest, crispiest, tenderest little pink beauties you ever saw--all the year round. No weed seeds in that soil, either." We rolled slowly back in the green shade. There was plenty of traffic, but all quiet, orderly, and comfortable. The people were a constant surprise to me. They were certainly better looking, even the poorest. And on the faces of the newest immigrants there was an expression of blazing hope that was almost better than the cheery peacefulness of the native born.