These latter ideas had made unknowing use of some basic physics, and I'm afraid I relapsed for a few minutes into the role of teacher and told them a little bit about the laws of radiation and absorption of heat.
"My," said Marjorie, "they're really smart boys and girls. Tommy Miller does sound like a born salesman. Somehow I don't think you're going to have to call in Mr. Wells."
I do feel just a little embarrassed about the kite, even now. The fact that it flew surprised me. That it flew so confoundedly well was humiliating. Four of them were at the barn when I arrived next morning; or rather on the rise of ground just beyond it, and the kite hung motionless and almost out of sight in the pale sky. I stood and watched for a moment, then they saw me.
"Hello, Mr. Henderson," Mary said, and proffered the cord which was wound on a fishing reel. I played the kite up and down for a few minutes, then reeled it in. It was, almost exactly, a wind sock, but the hole at the small end was shaped—by wire—into the general form of a kidney bean. It was beautifully made, and had a sort of professional look about it.
"It flies too well," Mary told Doris. "A kite ought to get caught in a tree sometimes."
"You're right," Doris agreed. "Let's see it." She gave the wire at the small end the slightest of twists. "There, it ought to swoop."
Sure enough, in the moderate breeze of that morning, the kite swooped and yawed to Mary's entire satisfaction. As we trailed back to the barn I asked Doris, "How did you know that flattening the lower edge of the hole would create instability?" She looked doubtful.
"Why it would have to, wouldn't it? It changed the pattern of air pressures." She glanced at me quickly. "Of course, I tried a lot of different shapes while I was making it."
"Naturally," I said, and let it go at that. "Where's Tommy?"
"He stopped off at the bank," Pete Cope told me, "to borrow some money. We'll want to buy materials to make some of these kites."