Barty pondered. "It looks better anyhow. And then, if you want to put cut stone, or beams, on top, you're all ready. Besides, it takes some practice to lay a wall that way, and you might as well be practicing all you can." The two men chuckled. A part of this, of course, Farmer Appleby already knew, but he had never explained to Barty. The boy went on. "The stones ought to be fitted so that the face of the wall is laid to a true line. If you slope it a little it's stronger, because that makes it wider at the bottom. But if you slope it too much the water won't run off and the snow will lie. If you've got any big stones put them where they will do the most good, 'cause you want the wall to be strong everywhere. A bigger stone that is pretty square, like this, can be a bond stone, and if you use one here and there it holds the wall together. David says the English gener'lly build a stone wall with a row of headers and then a row of stretchers, but in Flanders they lay a header and then a stretcher in every row." "How many loads of stone will it take for this wall?" asked David. Barty hesitated, measured with his eye, and then made a guess. "How much mortar?" He guessed again. The estimate was so near Farmer Appleby's own figures that he was betrayed into a whistle of surprise. "He's gey canny for a lad," said David, grinning. "He's near as wise as me. We've been at that game for a month." "Never lat on, but aye lat owre, Twa and twa they aye mak' fowre." Barty quoted a rhyme from David. "I reckon you've earned over and above your pay," said Farmer Appleby. He foresaw the usefulness of all this lore when Barty was a little older. The boy could direct a gang of heavy-handed laborers nearly as well as he could. "Any mason that's worth his salt will dae that," said David, unconcernedly. Barty was experimenting with his stone-laying when a hunting-party of strangers came down the bridle-path from the fens, where they had been hawking for a day. The fame of the Appleby culvert had spread through the country, and people often came to look at it, so that no one was surprised. The leader of the group was a middle-aged stout man, with close-clipped reddish hair, a full curly beard and a masterful way of speaking; he had a bow in his hand, and paced to and fro restlessly even when he was talking. "Who taught you to build walls, my boy?" asked a young man with bright dark eyes and a citole over his shoulder. "David," said Barty. "He's a Scot. When he was in France they called him David Saumond because of his leaping. He can dance fine." "And who taught David?" inquired the stranger. "The birds," Barty answered with a grin. "There's a song." "Let's have it," laughed the minstrel, and Barty sang.