"Substitute senna." So offhand was the tone that it sounded like a suggestion rather than an order. As the latter, however, the chemist contentedly took it. "It'll cost less," he observed; "and I guess it'll do the work just as well." To Hal it seemed a somewhat cavalier method of altering a medical formula. But his mind, accustomed to easy acceptance of the business which so luxuriously supplied his wants, passed the matter over lightly. "First-rate man, Dixon," remarked Dr. Surtaine as they passed along. "College-bred, and all that. Boozes, though. I only pay him twenty-five a week, and he's mighty glad to get it." On the way back to the offices, they traversed the checking and accounting rooms, the agency department, the great rows of desks whereat the shipping and mailing were looked after, and at length stopped before the door of a small office occupied by a dozen women. One of these, a full-bosomed, slender, warm-skinned girl with a wealth of deep-hued, rippling red hair crowning her small, well-poised head, rose and came to speak to Dr. Surtaine. "Did you get the message I sent you about Letter Number Seven?" she asked. "Hello, Milly," greeted the presiding genius, pleasantly. "Just what was that about Number Seven?" "It isn't getting results." "No? Let's see it." Dr. Surtaine was as interested in this as he had been casual about the drug alteration. "I don't think it's personal enough," pursued the girl, handing him a sheet of imitation typewriter print. "Oh, you don't," said her employer, amused. "Maybe you could better it." "I have," said the girl calmly. "You always tell us to make suggestions. Mine are on the back of the paper." "Good for you! Hal, here's the prettiest girl in the shop, and about the smartest. Milly, this is my boy." The girl looked up at Hal with a smile and brightened color. He was suddenly interested and appreciative to see to what a vivid prettiness her face was lighted by the raised glance of her swift, gray-green eyes. "Are you coming into the business, Mr. Surtaine?" she asked composedly, and with almost as proprietary an air as if she had said "our business." "I don't know. Is it the sort of business you would advise a rather lazy person to embark in, Miss--" "Neal," she supplied; adding, with an illustrative glance around, upon her busy roomful, all sorting and marking correspondence, "You see, I only give advice by letter." She turned away to answer one of the subordinates, and, at the same time, Dr. Surtaine was called aside by a man with a shipping-bill. Looking down the line of workers, Hal saw that each one was simply opening, reading, and marking with a single stroke, the letters from a distributing groove. To her questioner Milly Neal was saying, briskly: "That's Three and Seven. Can't you see, she says she has spots before her eyes. That's stomach. And the lameness in the side is kidneys. Mark it 'Three pass to Seven.' There's a combination form for that."