“But C^2 is not a velocity,” Haarland said. He turned to Ross. “Sorry to make a mystery,” he apologized. “It’s a recognition formula. It identifies one member of what we call the Wesley families, or its messenger, to another. And these people are messengers. They were dispatched a couple of centuries ago by a Wesley family whose ship, for some reason, no longer could be used. Why?—I don’t know why. Try your luck, maybe you can figure it out. Ma, tell us the history again.” She knitted her brows and began to chant slowly: “In great-grandfather’s time the target was Clyde, Rocketry firm and ores on the side. If we hadn’t of seen them direct we’d of missed ’em; There wasn’t a blip from the whole damn system. That was the first. Before great-grandfather’s day was done We cut the orbit of Cyrnus One. The contact there was Trader McCue, But the sons o’ bitches missed us too. That was the second. My grandpa lived to see the green Of Target Three through the high-powered screen. But where in hell was Builder Carruthers? They let us go by like all the others. That was the——” “Ma,” said Haarland. “Thanks very much, but would you skip to the last one?” Ma grinned. The Haarland Trading Corp. was last With the fuel down low and going fast. I’m glad it was me who saw the day When they brought us down on GCA. I told him the message; he called it a mystery, But anyway this is the end of the history. And it’s about time! “The message, please,” Haarland said broodingly. Ma took a deep breath and rattled off: “L-sub-T equals L-sub-zero e to the minus-T-over-two-N.” Ross gaped. “That’s the message?” “Used to be more to it,” Ma said cheerfully “That’s all there is now, though. The darn thing doesn’t rhyme or anything. I guess that’s the most important part. Anyway, it’s the hardest.” “It’s not as bad as it seems,” Haarland told Ross. “I’ve asked around. It makes a very little sense.” “It does?” “Well, up to a point,” Haarland qualified. “It seems to be a formula in genetics. The notation is peculiar, but it’s all explained, of course. It has something to do with gene loss. Now, maybe that means something and maybe it doesn’t. But I know something that does mean something: some member of a Wesley Family a couple of hundred years ago thought it was important enough to want to get it across to other Wesley families. Something’s happening. Let’s find out what it is, Ross.” The old man suddenly buried his face in his hands. In a cracked voice he mumbled, “Gene loss and war. Gene loss or war. God, I wish somebody would take this right out of my hands—or that I could drop with a heart attack this minute. You ever think of war, Ross?”