It was a quarter past four, and still night, when Coquenil left the HÔtel des Étrangers; he wore a soft black hat pulled down over his eyes, and a shabby black coat turned up around his throat; and he carried the leather bag taken from the automobile. The streets were silent and deserted, yet the detective studied every doorway and corner with vigilant care, while a hundred yards behind him, in exactly similar dress, came Papa Tignol, peering into the shadows with sharpest watchfulness against human shadows bent on harming M. Paul.

So they moved cautiously down the Boulevard St. Michel, then over the bridge and along the river to Notre-Dame, whose massive towers stood out in mysterious beauty against the faintly lighted eastern sky. Here the leader paused for his companion.

"There's nothing," he said, as the latter joined him.

"Nothing."

"Good! Take the bag and wait for me, but keep out of sight."

"Entendu."

Coquenil walked across the square to the cathedral, moving slowly, thinking over the events of the night. They had crossed the track of the assassin, that was sure, but they had discovered nothing that could help in his capture except the fact of the long little finger. The man had left absolutely nothing in his room at the hotel (this they verified with the help of false keys), and had never returned after the night of the crime, although he had taken the room for a month, and paid the rent in advance. He had made two visits to this room, one at about three in the afternoon of the fatal day, when he spent an hour there, and entered Kittredge's room, no doubt, for the boots and the pistol; the other visit he made the same night when he tried to return the boots and was prevented from doing so. How he must have cursed that little photographer!

As to the assassin's personal appearance, there was a startling difference of opinion between the hotel doorkeeper and the garÇon, both of whom saw him and spoke to him. The one declared he had light hair and a beard, the other that he had dark hair and no beard; the one thought he was a Frenchman, the other was sure he was a foreigner. Evidently the man was disguised either coming or going, so this testimony was practically worthless.

Despite all this, Coquenil was pleased and confident as he rang the night bell at the archbishop's house beside the cathedral, for he had one precious clew, he had the indication of this extraordinarily long little finger, and he did not believe that in all France there were two men with hands like that. And he knew there was one such man, for Alice had seen him. Where had she seen him? She said she had often noticed his long little finger, so she must often have been close enough to him to observe such a small peculiarity. But Alice went about very little, she had few friends, and all of them must be known to the Bonnetons. It ought to be easy to get from the sacristan this information which the girl herself might withhold. Hence this nocturnal visit to Notre Dame—it was of the utmost importance that Coquenil have an immediate talk with Papa Bonneton.

And presently, after a sleepy salutation from the archbishop's servant, and a brief explanation, M. Paul was shown through a stone passageway that connects the church with the house, and on pushing open a wide door covered with red velvet, he found himself alone in Notre Dame, alone in utter darkness save for a point of red light on the shadowy altar before the Blessed Sacrament.

As he stood uncertain which way to turn, the detective heard a step and a low growl, and peering among the arches of the choir he saw a lantern advancing, then a figure holding the lantern, then another crouching figure moving before the lantern. Then he recognized CÆsar.

"Phee-et, phee-et!" he whistled softly, and with a start and a glad rush, the dog came bounding to his master, while the sacristan stared in alarm.

"Good old CÆsar! There, there!" murmured Coquenil, fondling the eager head. "It's all right, Bonneton," and coming forward, he held out his hand as the guardian lifted his lantern in suspicious scrutiny.

"M. Paul, upon my soul!" exclaimed the sacristan. "What are you doing here at this hour?"

"It's a little—er—personal matter," coughed Coquenil discreetly, "partly about CÆsar. Can we sit down somewhere?"

Still wondering, Bonneton led the way to a small room adjoining the treasure chamber, where a dim lamp was burning; here he and his associates got alternate snatches of sleep during the night.

"Hey, FranÇois!" He shook a sleeping figure on a cot bed, and the latter roused himself and sat up. "It's time to make the round."

FranÇois looked stupidly at Coquenil and then, with a yawn and a shrug of indifference, he called to the dog, while CÆsar growled his reluctance.

"It's all right, old fellow," encouraged Coquenil, "I'll see you again," whereupon CÆsar trotted away reassured.

"Take this chair," said the sacristan. "I'll sit on the bed. We don't have many visitors."

"Now, then," began M. Paul. "I'll come to the dog in a minute—don't worry. I'm not going to take him away. But first I want to ask about that girl who sells candles. She boards with you, doesn't she?"

"Yes."

"You know she's in love with this American who's in prison?"

"I know."

"She came to see me the other day."

"She did?"

"Yes, and the result of her visit was—well, it has made a lot of trouble. What I'm going to say is absolutely between ourselves—you mustn't tell a soul, least of all your wife."

"You can trust me, M. Paul," declared Papa Bonneton rubbing his hands in excitement.

"To begin with, who is the man with the long little finger that she told me about?" He put the questions carelessly, as if it were of no particular moment.

"Why, that's Groener," answered Bonneton simply.

"Groener? Oh, her cousin?"

"Yes."

"I'm interested," went on the detective with the same indifferent air, "because I have a collection of plaster hands at my house—I'll show it to you some day—and there's one with a long little finger that the candle girl noticed. Is her cousin's little finger really very long?"

"It's pretty long," said Bonneton. "I used to think it had been stretched in some machine. You know he's a wood carver."

"I know. Well, that's neither here nor there. The point is, this girl had a dream that—why, what's the matter?"

"Don't talk to me about her dreams!" exclaimed the sacristan. "She used to have us scared to death with 'em. My wife won't let her tell 'em any more, and it's a good thing she won't." For a mild man he spoke with surprising vehemence.

"Bonneton," continued the detective mysteriously, "I don't know whether it's from her dreams or in some other way, but that girl knows things that—that she has no business to know."

Then, briefly and impressively, Coquenil told of the extraordinary revelations that Alice had made, not only to him, but to the director of the SantÉ prison.

"Mon Dieu, mon Dieu!" muttered the old man. "I think she's possessed of the devil."

"She's possessed of dangerous knowledge, and I want to know where she got it. I want to know all about this girl, who she is, where she came from, everything. And that's where you can help me."

Bonneton shook his head. "We know very little about her, and, the queer thing is, she seems to know very little about herself."

"Perhaps she knows more than she wants to tell."

"Perhaps, but—I don't think so. I believe she is perfectly honest. Anyhow, her cousin is a stupid fellow. He comes on from Brussels every five or six months and spends two nights with us—never more, never less. He eats his meals, attends to his commissions for wood carving, takes Alice out once in the afternoon or evening, gives my wife the money for her board, and that's all. For five years it's been the same—you know as much about him in one visit as you would in a hundred. There's nothing much to know; he's just a stupid wood carver."

"You say he takes Alice out every time he comes? Is she fond of him?"

"Why—er—yes, I think so, but he upsets her. I've noticed she's nervous just before his visits, and sort of sad after them. My wife says the girl has her worst dreams then."

Coquenil took out a box of cigarettes. "You don't mind if I smoke?" And, without waiting for permission, he lighted one of his Egyptians and inhaled long breaths of the fragrant smoke. "Not a word, Bonneton! I want to think." Then for full five minutes he sat silent.

"I have it!" he exclaimed presently. "Tell me about this man FranÇois."

"FranÇois?" answered the sacristan in surprise. "Why, he helps me with the night work here."

"Where does he live?"

"In a room near here."

"Where does he eat?"

"He takes two meals with us."

"Ah! Do you think he would like to make a hundred francs by doing nothing? Of course he would. And you would like to make five hundred?"

"Five hundred francs?" exclaimed Bonneton, with a frightened look.

"Don't be afraid," laughed the other. "I'm not planning to steal the treasure. When do you expect this wood carver again?"

"It's odd you should ask that, for my wife only told me this morning she's had a letter from him. We didn't expect him for six weeks yet, but it seems he'll be here next Wednesday. Something must have happened."

"Next Wednesday," reflected Coquenil. "He always comes when he says he will?"

"Always. He's as regular as clockwork."

"And he spends two nights with you?"

"Yes."

"That will be Wednesday night and Thursday night of next week?"

"Yes."

"Good! Now I'll show you how you're going to make this money. I want FranÇois to have a little vacation; he looks tired. I want him to go into the country on Tuesday and stay until Friday."

"And his work? Who will do his work?"

Coquenil smiled quietly and tapped his breast.

"You?"

"I will take FranÇois's place. I'll be the best assistant you ever had and I shall enjoy Mother Bonneton's cooking."

"You will take your meals with us?" cried the sacristan aghast. "But they all know you."

"None of them will know me; you won't know me yourself."

"Ah, I see," nodded the old man wisely. "You will have a disguise. But my wife has sharp eyes."

"If she knows me, or if the candle girl knows me, I'll give you a thousand francs instead of five hundred. Now, here is the money for FranÇois"—he handed the sacristan a hundred-franc note—"and here are five hundred francs for you. I shall come on Tuesday, ready for work. When do you want me?"

"At six o'clock," answered the sacristan doubtfully. "But what shall I say if anyone asks me about it?"

"Say FranÇois was sick, and you got your old friend Matthieu to replace him for a few days. I'm Matthieu!"

Papa Bonneton touched the five crisp bank notes caressingly; their clean blue and white attracted him irresistibly.

"You wouldn't get me into trouble, M. Paul?" he appealed weakly.

"Papa Bonneton," answered Coquenil earnestly, "have I ever shown you anything but friendship? When old Max died and you asked me to lend you CÆsar I did it, didn't I? And you know what CÆsar is to me. I love that dog, if anything happened to him—well, I don't like to think of it, but I let you have him, didn't I? That proves my trust; now I want yours. I can't explain my reasons; it isn't necessary, but I tell you that what I'm asking cannot do you the least harm, and may do me the greatest good. There, it's up to you."

M. Paul held out his hand frankly and the sacristan took it, with emotion.

"That settles it," he murmured. "I never doubted you, but—my wife has an infernal tongue and——"

"She will never know anything about this," smiled the other, "and, if she should, give her one or two of these bank notes. It's wonderful how they change a woman's point of view. Besides, you can prepare her by talking about FranÇois's bad health."

"A good idea!" brightened Bonneton.

"Then it's understood. Tuesday, at six, your friend Matthieu will be here to replace FranÇois. Remember—Matthieu!"

"I'll remember."

The detective rose to go. "Good night—or, rather, good morning, for the day is shining through that rose window. Pretty, isn't it? Ouf, I wonder when I'll get the sleep I need!" He moved toward the door. "Oh, I forgot about the dog. Tignol will come for him Tuesday morning with a line from me. I shall want CÆsar in the afternoon, but I'll bring him back at six."

"All right," nodded the sacristan; "he'll be ready. Au revoir—until Tuesday."

M. Paul went through the side door and then through the high iron gateway before the archbishop's house. He glanced at his watch and it was after five. Across the square Papa Tignol was waiting.

"Things are marching along," smiled Coquenil some minutes later as they rolled along toward the Eastern railway station. "You know what you have to do. And I know what I have to do! Bon Dieu! what a life! You'd better have more money—here," and he handed the other some bank notes. "We meet Tuesday at noon near the Auteuil station beneath the first arch of the viaduct."

"Do you know what day Tuesday is?"

M. Paul thought a moment. "The fourteenth of July! Our national holiday! And the crime was committed on the American Independence Day. Strange, isn't it?"

"There will be a great crowd about."

"There's safety in a crowd. Besides, I've got to suit my time to his."

"Then you really expect to see—him?" questioned the old man.

"Yes," nodded the other briefly. "Remember this, don't join me on Tuesday or speak to me or make any sign to me unless you are absolutely sure you have not been followed. If you are in any doubt, put your message under the dog's collar and let him find me. By the way, you'd better have CÆsar clipped. It's a pity, but—it's safer."

Now they were rattling up the Rue Lafayette in the full light of day.

"Ten minutes to six," remarked Tignol. "My train leaves at six forty."

"You'll have time to get breakfast. I'll leave you now. There's nothing more to say. You have my letter—for her. You'll explain that it isn't safe for me to write through the post office. And she mustn't try to write me. I'll come to her as soon as I can. You have the money for her; say I want her to buy a new dress, a nice one, and if there's anything else she wants, why, she must have it. Understand?"

Tignol nodded.

Then, dropping the cab window, M. Paul told the driver to stop, and they drew up before the terraced fountains of the TrinitÉ church.

"Good-by and good luck," said Coquenil, clasping Tignol's hand, "and—don't let her worry."

The cab rolled on, and M. Paul, bag in hand, strode down a side street; but just at the corner he turned and looked after the hurrying vehicle, and his eyes were full of sadness and yearning.

Tuesday, the fourteenth of July! The great French holiday! All Paris in the streets, bands playing, soldiers marching, everybody happy or looking happy! And from early morning all trains, 'buses, cabs, automobiles, in short, all moving things in the gay city were rolling a jubilant multitude toward the Bois de Boulogne, where the President of the Republique was to review the troops before a million or so of his fellow-citizens. Coquenil had certainly chosen the busiest end of Paris for his meeting with Papa Tignol.

Their rendezvous was at noon, but two hours earlier Tignol took the train at the St. Lazare station. And with him came CÆsar, such a changed, unrecognizable CÆsar! Poor dog! His beautiful, glossy coat of brown and white had been clipped to ridiculous shortness, and he crouched at the old man's feet in evident humiliation.

"It was a shame, old fellow," said Tignol consolingly, "but we had to obey orders, eh? Never mind, it will grow out again."

Leaving the train at Auteuil, they walked down the Rue La Fontaine to a tavern near the Rue Mozart, where the old man left CÆsar in charge of the proprietor, a friend of his. It was now a quarter to eleven, and Tignol spent the next hour riding back and forth on the circular railway between Auteuil and various other stations; he did this because Coquenil had charged him to be sure he was not followed; he felt reasonably certain that he was not, but he wished to be absolutely certain.

So he rode back to the Avenue Henri Martin, where he crossed the platform and boarded a returning train for the Champs de Mars, telling the guard he had made a mistake. Two other passengers did the same, a young fellow and a man of about fifty, with a rough gray beard. Tignol did not see the young fellow again, but when he got off at the Champs de Mars, the gray-bearded man got off also and followed across the bridge to the opposite platform, where both took the train back to Auteuil.

This was suspicious, so at Auteuil Tignol left the station quickly, only to return a few minutes later and buy another ticket for the Avenue Henri Martin. There once more he crossed the platform and took a train for the Champs de Mars, and this time he congratulated himself that no one had followed him; but when he got off, as before, at the Champs de Mars and crossed the bridge, he saw the same gray-bearded man crossing behind him. There was no doubt of it, he was being shadowed.

And now Tignol waited until the train back to Auteuil was about starting, then he deliberately got into a compartment where the gray-bearded man was seated alone. And, taking out pencil and paper, he proceeded to write a note for Coquenil. Their meeting was now impossible, so he must fasten this explanation, along with his full report, under CÆsar's collar and let the dog be messenger, as had been arranged.

"I am sending this by CÆsar," he wrote, "because I am watched. The man following me is a bad-looking brute with dirty gray beard and no mustache. He has a nervous trick of half shutting his eyes and jerking up the corners of his mouth, which shows the worst set of ugly yellow teeth I ever saw. I'd like to have one of them for a curiosity."

"Would you?" said the man suddenly, as if answering a question.

Tignol stared at him.

"Excuse me," explained the other, "but I read handwriting upside down."

"Oh!"

"You say you would like one of my teeth?"

"Don't trouble," smiled Tignol.

"It's no trouble," declared the stranger. "On the contrary!" and seizing one of his yellow fangs between thumb and first finger he gave a quick wrench. "There!" he said with a hideous grin, and he handed Tignol the tooth.

They were just coming into the Auteuil station as this extraordinary maneuver was accomplished.

"I'll be damned!" exclaimed Tignol.

"'There!' he said with a hideous grin, and he handed Tignol the tooth."

"Is it really as good as that?" asked the stranger, in a tone that made the old man jump.

Tignol leaned closer, and then in a burst of admiration he cried: "Nom de dieu! It's Coquenil!"