"Carried many a thousand of our money to bank for us, Boyee. That's the ad. that made the business." "Did you design it?" "Every word and every line, except that I got a cheap artist to touch up the drawing a little. Then I plunged. When that copy went out, we had just fifty thousand dollars in the world, you and I. Before it had been running three months, I'd spent one hundred thousand dollars more than we owned, in the newspapers, and had to borrow money right and left to keep the manufacturing and bottling plant up to the orders. It was a year before we could see clear sailing, and by that time we were pretty near quarter of a million to the good. Talk about ads. that pull! It pulled like a mule-team and a traction engine and a fifty-cent painless dentist all in one. I'm still using that copy, in the kidney season." "Do kidneys have seasons?" "Kidney troubles do." "I'd have thought such diseases wouldn't depend on the time of year." "Maybe they don't, actually," admitted the other. "Maybe they're just crowded out of the public mind by the pressure of other sickness in season, like rheumatism in the early winter, and pneumonia in the late. But there's no doubt that the kidney season comes in with the changes of the spring. That's one of my discoveries, too. I tell you, Boyee, I've built my success on things like that. It's psychology: that's what it is. That's what you've got to learn, if you're going into the concern." "I'm ready, Dad. It sounds interesting. More so than I'd have thought." "Interesting! It's the very heart and core of the trade." Dr. Surtaine leaned forward, to tap with an earnest finger on his son's knee, a picture of expository enthusiasm. "Here's the theory. You see, along about March or April people begin to get slack-nerved and out-of-sortsy. They don't know what ails 'em, but they think there's something. Well, one look at that ad. sets 'em wondering if it isn't their kidneys. After wonder comes worry. He's the best little worrier in the trade, Old Lame-Boy is. He just pesters folks into taking proper care of themselves. They get Certina, and we get their dollars. And they get their money's worth, too," he added as an afterthought for Hal's benefit, "for it's a mighty good thing to have your kidneys tonicked up at this time of year." "But, Dad," queried Hal, with an effort of puzzled reminiscence, "in the old days Certina wasn't a kidney remedy, was it?" "Not specially. It's always been _good_ for the kidneys. Good for everything, for that matter. Besides, the formula's been changed." "Changed? But the formula's the vital thing, isn't it?" "Yes, yes. Of course. Certainly it's the vital thing: certainly. But, you see,--well,--new discoveries in medicine and that sort of thing." "You've put new drugs in?"