"So that's how I came into possession of the book. I sold it to Vining at Burtnoe's, as you no doubt know."

"But," exclaimed Lucile breathlessly, feeling that the scent was growing fresher all the while, "from whom did the doctor purchase it at so ridiculous a price?"

"From a fool bookstorekeeper of course; one of those upstarts who know nothing at all about books; who handle them as pure merchandise, purchased at so much and sold for forty and five per cent more, regardless of actual value. He'd bought it to help out some ignorant foreigner, a Spaniard I believe. He'd paid ten dollars and had been terribly pleased within himself when he made five on the deal."

"Who was he?" Lucile asked eagerly, "and where was his shop?"

"That I didn't trouble to find out. Very likely he's out of business by now. Such shops are like gra.s.s in autumn, soon die down and the snow covers them up. The doctor could tell you though. I'll give you his address and you may go and ask him."

The short afternoon was near spent and the shades of night were already falling when at last Lucile entered the shop of the unfortunate bookseller who had not realized the value of the little book. Lunch had delayed her, then the doctor had been out making calls and had kept her waiting for two hours. The little shop had been hard to find, but here at last she was.

A pitiful shop it was, possessing but a few hundred volumes and presided over by a grimy-fingered man who might but the day before have been promoted from the garbage wagon so far as personal appearance was concerned. Indeed, as Lucile looked over the place she was seized with the crazy notion that the whole place, books, shelves and proprietor, had but recently climbed down from the junk cart.

"And yet," she told herself, "it was from this very heap of dusty paper and cardboard that this precious bit of literature which I have in my pocket, was salvaged. I must not forget that.

"I believe," she told herself with an excited intake of breath, "that I am coming close to the end of my search. All day I have been descending step by step; first the wonderful Burtnoe's Book Store with all its magnificence and its genius of a bookman, then Dan Whitner and the doctor, now this place, and then perhaps, whoever the person is who sold the book to this pitiful specimen of a bookseller."

Her heart skipped a beat as the bookman, having caught sight of her, began to amble in her direction.

She made her question short and to the point. "Where did you get this book?"

"That book?" he took it and turned it over in his hand. He scratched his head. "That, why that book must have been one I bought with a lot at an auction sale last week. Want'a buy it?"

"No. No!" exclaimed Lucile, seizing the book. "It's not your book. It is mine but you had it once and sold it. What I wish to know is, where did you get it?"

Three customers were thumbing through the books. One seated at a table turned and looked up. His face impressed the girl at once as being particularly horrible. Dark featured, hook-nosed, with a blue birthmark covering half his chin, he inspired her with an almost uncontrollable fear.

"We--we--" she faltered "--may we not step back under the light where you can see the book better?"

The shopkeeper followed her in stolid silence.

It was necessary for her to tell him the whole story of the purchase and sale of the book before he recognized it as having once been on his shelves.

"Oh, yes," he exclaimed at last. "Made five dollars on her. Thought I had made a mistake, but didn't; not that time I didn't. Where'd I get her?

Let's see?"

As he stood there attempting to recall the name of the purchaser, Lucile's gaze strayed to an opening between two rows of books. Instantly her eyes were caught as a bird's by a serpent, as she found herself looking into a pair of cruel, crafty, prying eyes. They vanished instantly but left her with a cold chill running up her spine. It was the man who had been seated at the table, but why had he been spying? She had not long to wait before a possible solution was given her.

"I know!" exclaimed the shopkeeper at this instant, "I bought it from a foreigner. Bought two others from him, too. Made good money on 'em all, too. Why!" he exclaimed suddenly, "he was in here when you came. Had another book under his arm, he did; wanted to sell it, I judge. I was just keeping him waiting a little so's he wouldn't think I wanted it too bad. If they think you want their books bad they stick for a big price."

His voice had dropped to a whisper; his eyes had narrowed to what was meant to be a very wise-meaning expression.

"May be here yet." He darted around the stand of books.

"That's him just going out the door. Hey, you!" he shouted after the man.

Paying not the least attention, the person pa.s.sed out, slamming the door after him.

Pa.s.sing rapidly down the room, the proprietor poked his head out of the door and shouted twice. After listening for a moment he backed into the room and shut the door.

"Gone," he muttered. "Worse luck to me. Sometimes we wait too long and sometimes not long enough. Now some other lucky dog will get that book."

In the meantime Lucile had glanced about the shop. Two persons were reading beneath a lamp in the corner. Neither was the man with the birthmark. It was natural enough to conclude that it was he who had left the room.

"Did he have a birthmark on his chin, this man you bought the book from?"

she asked as the proprietor returned.

"Yes, ma'am, he did."

"Then I saw him here a moment ago. When is he likely to return?"

"That no one can tell. Perhaps to-morrow, perhaps never. He has not been here before in three months. Did you wish to speak with him?"

Lucile shivered. "Well, perhaps not," she half whispered.

"Huh!" grunted the proprietor suddenly, "what's this? Must be the book he brought. He's forgotten it. Now he is sure to be back."

Lucile was rather of the opinion that he would not soon return. She believed that there had been some trickery about the affair of these valuable books which were being sold to the cheapest book dealer in the city for a very small part of their value. "Perhaps they were stolen,"

she told herself. At once the strangeness of the situation came to her; here she was with a book in her possession which had been but recently stolen from Frank Morrow's book shop by a girl and now circ.u.mstances seemed to indicate that this very book had been stolen by some person who had sold it to this bookmonger, who had pa.s.sed it on to the doctor who had sold it to Dan Whitner, who had sold it to Roderick Vining, who had sold it to Frank Morrow.

"Sounds like the house that Jack built," she whispered to herself. "But then I suppose some valuable books have been stolen many times. Frank Morrow said one of his had been stolen twice within a week by totally different persons."

Turning to the shopkeeper, she asked if she might see the book that had been left behind.

As she turned back the cover a low exclamation escaped her lips. In the corner of that cover was the same secret mark as had been in all the mystery books, the gargoyle and the letter L.

Hiding her surprise as best she could, she handed the book to the man with the remark:

"Of course you cannot sell the book, since it is not your own?"

"I'd chance it."

"I'll give you ten dollars for it. If he returns and demands more, I will either pay the price or return the book. I'll give you my address."

"Done!" he exclaimed. "I don't think you'll ever hear from me. I'll give him seven and he'll be glad enough to get it. Pretty good, eh?" he rubbed his hands together gleefully. "Three dollars clean profit and not a cent invested any of the time."

Like the ancient volume on fishing, this newly acquired book was small and thin, so without examining its contents she thrust it beside the other in the large pocket of her coat.

"I suppose I oughtn't to have done it," she whispered to herself as she left the shop, "but if I hadn't, he'd have sold it to the first customer.

It's evidence in the case and besides it may be valuable."

A fog hung over the city. The streets were dark and damp. Here and there a yellow light struggled to pierce the denseness of the gloom. As she turned to the right and walked down the street, not knowing for the moment quite what else to do, she fancied that a shadow darted down the alley to her left.

"Too dark to tell. Might have been a dog or anything," she murmured. Yet she shivered and quickened her pace. She was in a great, dark city alone and she was going--where? That she did not know. The day's adventures had left her high and dry on the streets of a city as a boat is left by the tide on the sand.

CHAPTER XXI A THEFT IN THE NIGHT