The names of the other two collectors were John Hinchman and J. S. Peters. A detective attached to the precinct had visited each in turn, and had then gone to the address of Beninson. Beninson, who presumably had been the man with black mustaches and blue-tinted spectacles, was ignorant of the entire affair; and his physical appearance did not tally with the description of Ulm’s assailant. He had received no invitation from the Ulm brothers, he said, to attend the private sale. Yes, he had had an employee, a man with black mustaches and tinted glasses, for two weeks — this man had answered Beninson’s advertisement for an assistant to take charge of the collector’s private stamp albums, had proved satisfactory, and had suddenly, without explanation or notice, disappeared after two weeks’ service. He had disappeared, the detective noted, on the morning of the Ulms’ sale.
All attempts to trace this mysterious assistant, who had called himself William Planck, were unsuccessful. The man had vanished among New York City’s millions.
Nor was this the end of the story. For the day after the theft old Uneker himself had reported to the precinct detective a queer tale. The previous night — the night of the Ulm theft — said Uneker, he had left his shop for a late dinner; his night clerk had remained on duty. A man had entered the shop, had asked to see Europe in Chaos, and had then to the night clerk’s astonishment purchased all copies of the book in stock — seven. The man who had made this extraordinary purchase wore black mustaches and blue-tinted spectacles!
“Sort of nuts, ain’t it?” growled Sergeant Velie.
“Not at all,” smiled Ellery. “In fact, I believe it has a very simple explanation.”
“And that ain’t the half of it. One of the boys told me just now of a new angle on the case. Two minor robberies were reported from local precincts last night. One was uptown in the Bronx; a man named Hornell said his apartment was broken into during the night, and what do you think? Copy of Europe in Chaos which Hornell had bought in this guy Uneker’s store was stolen! Nothin’ else. Bought it two days ago. Then a dame named Janet Meakins from Greenwich Village had her flat robbed the same night. Thief had taken her copy of Europe in Chaos — she’d bought it from Uneker the afternoon before. Screwy, hey?”
“Not at all, Velie. Use your wits.” Ellery clapped his hat on his head. “Come along, you Colossus; I want to speak to old Unky again.”
They left headquarters and went uptown.
“Unky,” said Ellery, patting the little old bookseller’s bald pate affectionately, “how many copies of Europe in Chaos did you have in stock at the time the thief escaped from your back room?”
“Eleffen.”
“Yet only seven were in stock that same evening when the thief returned to buy them,” murmured Ellery. “Therefore, four copies had been sold between the noon hour two days ago and the dinner hour. So! Unky, do you keep a record of your customers?”
“Ach, yes! De few who buy,” said old Uneker sadly. “I addt to my mailing lisdt. You vant to see?”
“There is nothing I crave more ardently at the moment.”
Uneker led them to the rear of the shop and through a door into the musty back room from whose alley door the thief had escaped two days before. Off this room there was a partitioned cubicle littered with papers, files, and old books. The old bookseller opened a ponderous ledger and, wetting his ancient forefinger, began to slap pages over. “You vant to know de four who boughdt Europe in Chaos dot afternoon?”
“Ja.”
Uneker hooked a pair of greenish-silver spectacles over his ears and began to read in a singsong voice. “Mr. Hazlitt — dot’s the gentleman you met, Mr. Quveen. He boughdt his second copy, de vim dot vass robbed from his house... Den dere vass Mr. Hornell, an oldt customer. Den a Miss Janet Meakins — ach! dese Anglo-Saxon names. Schrecklich! Undt de fourt’ vim vass Mr. Chester Singermann, uff t’ree-tvelf East Siggsty-fift’ Street. Und dot’s all.”
“Bless your orderly old Teutonic soul,” said Ellery. “Velie, cast those Cyclopean peepers of yours this way.” There was a door from the cubicle which, from its location, led out into the alley at the rear, like the door in the back room. Ellery bent over the lock; it was splintered away from the wood.
He opened the door; the outer piece was scratched and mutilated. Velie nodded. “Forced,” he growled. “This guy’s a regular Houdini.”
Old Uneker was goggle-eyed. “Broken!” he shrilled. “But dot door iss neffer usedt. I didn’t notice no’ting, undt de detectiff—”
“Shocking work, Velie, on the part of the local man,” said Ellery. “Unky, has anything been stolen?” Old Uneker flew to an antiquated bookcase; it was neatly tiered with volumes. He unlocked the case with anguished fingers, rummaging like an aged terrier. Then he heaved a vast sigh. “Nein,” he said. “Dose rare vons... Not’ing stole.”
“I congratulate you. One thing more,” said Ellery briskly. “Your mailing list — does it have the business as well as private addresses of your customers?” Uneker nodded. “Better and better. Ta-ta, Unky. You may have a finished story to relate to your other customers after all. Come along, Velie; we’re going to visit Mr. Chester Singermann.”
They left the bookshop, walked over to Fifth Avenue, and turned north heading uptown. “Plain as the nose on your face,” said Ellery, stretching his long stride to match Velie’s. “And that’s pretty plain, Sergeant.”
“Still looks nutty to me, Mr. Queen.”
“On the contrary, we are faced with a strictly logical set of facts. Our thief stole a valuable stamp. He dodged into Uneker’s bookshop, contrived to get into the back room. He heard the officer and Friederich Ulm enter, and got busy thinking. If he were caught with the stamp on his person... You see, Velie, the only explanation that will make consistent the business of the subsequent thefts of the same book — a book not valuable in itself — is that the thief, Planck, slipped the stamp between the pages of one of the volumes on a shelf while he was in the back room — it happened by accident to be a copy of Europe in Chaos, one of a number kept in stock on the shelf — and made his escape immediately thereafter. But he still had the problem of regaining possession of the stamp — what did Ulm call it? — the ‘one-penny black,’ whatever that may be. So that night he came back, watched for old Uneker to leave the shop, then went in and bought from the clerk all copies of Europe in Chaos in the place. He got seven. The stamp was not in any one of the seven he purchased, otherwise why did he later steal others which had been bought that afternoon? So far, so good. Not finding the stamp in any of the seven, then, he returned, broke into Unky’s little office during the night — witness the shattered lock — from the alley, and looked up in Unky’s Dickensian ledger the names and addresses of those who had bought copies of the book during that afternoon. The next night he robbed Hazlitt; Planck evidently followed him from his office. Planck saw at once that he had made a mistake; the condition of the weeks-old book would have told him that this wasn’t a book purchased only the day before. So he hurried out to East Orange, knowing Hazlitt’s private as well as business address, and stole Hazlitt’s recently purchased copy. No luck there either, so he feloniously visited Hornell and Janet Meakins, stealing their copies. Now, there is still one purchaser unaccounted for, which is why we are calling upon Singermann. For if Planck was unsuccessful in his theft of Hornell’s and Miss Meakins’ books, he will inevitably visit Singermann, and we want to beat our wily thief to it if possible.”