in carrying out victoire, the inspector had left the door of the drawing-room open. after he had watched m. formery reflect for two minutes, guerchard faded—to use an expressive americanism—through it. the duke felt in the breast-pocket of his coat, murmured softly, "my cigarettes," and followed him.

he caught up guerchard on the stairs and said, "i will come with you, if i may, m. guerchard. i find all these investigations extraordinarily interesting. i have been observing m. formery's methods—i should like to watch yours, for a change."

"by all means," said guerchard. "and there are several things i want to hear about from your grace. of course it might be an advantage to discuss them together with m. formery, but—" and he hesitated.

"it would be a pity to disturb m. formery in the middle of the process of reconstruction," said the duke; and a faint, ironical smile played round the corners of his sensitive lips.

guerchard looked at him quickly: "perhaps it would," he said.

they went through the house, out of the back door, and into the garden. guerchard moved about twenty yards from the house, then he stopped and questioned the duke at great length. he questioned him first about the charolais, their appearance, their actions, especially about bernard's attempt to steal the pendant, and the theft of the motor-cars.

"i have been wondering whether m. charolais might not have been arsene lupin himself," said the duke.

"it's quite possible," said guerchard. "there seem to be no limits whatever to lupin's powers of disguising himself. my colleague, ganimard, has come across him at least three times that he knows of, as a different person. and no single time could he be sure that it was the same man. of course, he had a feeling that he was in contact with some one he had met before, but that was all. he had no certainty. he may have met him half a dozen times besides without knowing him. and the photographs of him—they're all different. ganimard declares that lupin is so extraordinarily successful in his disguises because he is a great actor. he actually becomes for the time being the person he pretends to be. he thinks and feels absolutely like that person. do you follow me?"

"oh, yes; but he must be rather fluid, this lupin," said the duke; and then he added thoughtfully, "it must be awfully risky to come so often into actual contact with men like ganimard and you."

"lupin has never let any consideration of danger prevent him doing anything that caught his fancy. he has odd fancies, too. he's a humourist of the most varied kind—grim, ironic, farcical, as the mood takes him. he must be awfully trying to live with," said guerchard.

"do you think humourists are trying to live with?" said the duke, in a meditative tone. "i think they brighten life a good deal; but of course there are people who do not like them—the middle-classes."

"yes, yes, they're all very well in their place; but to live with they must be trying," said guerchard quickly.

he went on to question the duke closely and at length about the household of m. gournay-martin, saying that arsene lupin worked with the largest gang a burglar had ever captained, and it was any odds that he had introduced one, if not more, of that gang into it. moreover, in the case of a big affair like this, lupin himself often played two or three parts under as many disguises.

"if he was charolais, i don't see how he could be one of m. gournay-martin's household, too," said the duke in some perplexity.

"i don't say that he was charolais," said guerchard. "it is quite a moot point. on the whole, i'm inclined to think that he was not. the theft of the motor-cars was a job for a subordinate. he would hardly bother himself with it."

the duke told him all that he could remember about the millionaire's servants—and, under the clever questioning of the detective, he was surprised to find how much he did remember—all kinds of odd details about them which he had scarcely been aware of observing.

the two of them, as they talked, afforded an interesting contrast: the duke, with his air of distinction and race, his ironic expression, his mobile features, his clear enunciation and well-modulated voice, his easy carriage of an accomplished fencer—a fencer with muscles of steel—seemed to be a man of another kind from the slow-moving detective, with his husky voice, his common, slurring enunciation, his clumsily moulded features, so ill adapted to the expression of emotion and intelligence. it was a contrast almost between the hawk and the mole, the warrior and the workman. only in their eyes were they alike; both of them had the keen, alert eyes of observers. perhaps the most curious thing of all was that, in spite of the fact that he had for so much of his life been an idler, trifling away his time in the pursuit of pleasure, except when he had made his expedition to the south pole, the duke gave one the impression of being a cleverer man, of a far finer brain, than the detective who had spent so much of his life sharpening his wits on the more intricate problems of crime.

when guerchard came to the end of his questions, the duke said: "you have given me a very strong feeling that it is going to be a deuce of a job to catch lupin. i don't wonder that, so far, you have none of you laid hands on him."

"but we have!" cried guerchard quickly. "twice ganimard has caught him. once he had him in prison, and actually brought him to trial. lupin became another man, and was let go from the very dock."

"really? it sounds absolutely amazing," said the duke.

"and then, in the affair of the blue diamond, ganimard caught him again. he has his weakness, lupin—it's women. it's a very common weakness in these masters of crime. ganimard and holmlock shears, in that affair, got the better of him by using his love for a woman—'the fair-haired lady,' she was called—to nab him."

"a shabby trick," said the duke.

"shabby?" said guerchard in a tone of utter wonder. "how can anything be shabby in the case of a rogue like this?"

"perhaps not—perhaps not—still—" said the duke, and stopped.

the expression of wonder faded from guerchard's face, and he went on, "well, holmlock shears recovered the blue diamond, and ganimard nabbed lupin. he held him for ten minutes, then lupin escaped."

"what became of the fair-haired lady?" said the duke.

"i don't know. i have heard that she is dead," said guerchard. "now i come to think of it, i heard quite definitely that she died."

"it must be awful for a woman to love a man like lupin—the constant, wearing anxiety," said the duke thoughtfully.

"i dare say. yet he can have his pick of sweethearts. i've been offered thousands of francs by women—women of your grace's world and wealthy viennese—to make them acquainted with lupin," said guerchard.

"you don't surprise me," said the duke with his ironic smile. "women never do stop to think—where one of their heroes is concerned. and did you do it?"

"how could i? if i only could! if i could find lupin entangled with a woman like ganimard did—well—" said guerchard between his teeth.

"he'd never get out of your clutches," said the duke with conviction.

"i think not—i think not," said guerchard grimly. "but come, i may as well get on."

he walked across the turf to the foot of the ladder and looked at the footprints round it. he made but a cursory examination of them, and took his way down the garden-path, out of the door in the wall into the space about the house that was building. he was not long examining it, and he went right through it out into the street on which the house would face when it was finished. he looked up and down it, and began to retrace his footsteps.

"i've seen all i want to see out here. we may as well go back to the house," he said to the duke.

"i hope you've seen what you expected to see," said the duke.

"exactly what i expected to see—exactly," said guerchard.

"that's as it should be," said the duke.

they went back to the house and found m. formery in the drawing-room, still engaged in the process of reconstruction.

"the thing to do now is to hunt the neighbourhood for witnesses of the departure of the burglars with their booty. loaded as they were with such bulky objects, they must have had a big conveyance. somebody must have noticed it. they must have wondered why it was standing in front of a half-built house. somebody may have actually seen the burglars loading it, though it was so early in the morning. bonavent had better inquire at every house in the street on which that half-built house faces. did you happen to notice the name of it?" said m. formery.

"it's sureau street," said guerchard. "but dieusy has been hunting the neighbourhood for some one who saw the burglars loading their conveyance, or saw it waiting to be loaded, for the last hour."

"good," said m. formery. "we are getting on."

m. formery was silent. guerchard and the duke sat down and lighted cigarettes.

"you found plenty of traces," said m. formery, waving his hand towards the window.

"yes; i've found plenty of traces," said guerchard.

"of lupin?" said m. formery, with a faint sneer.

"no; not of lupin," said guerchard.

a smile of warm satisfaction illumined m. formery's face:

"what did i tell you?" he said. "i'm glad that you've changed your mind about that."

"i have hardly changed my mind," said guerchard, in his husky, gentle voice.

there came a loud knocking on the front door, the sound of excited voices on the stairs. the door opened, and in burst m. gournay-martin. he took one glance round the devastated room, raised his clenched hands towards the ceiling, and bellowed, "the scoundrels! the dirty scoundrels!" and his voice stuck in his throat. he tottered across the room to a couch, dropped heavily to it, gazed round the scene of desolation, and burst into tears.

germaine and sonia came into the room. the duke stepped forward to greet them.

"do stop crying, papa. you're as hoarse as a crow as it is," said germaine impatiently. then, turning on the duke with a frown, she said: "i think that joke of yours about the train was simply disgraceful, jacques. a joke's a joke, but to send us out to the station on a night like last night, through all that heavy rain, when you knew all the time that there was no quarter-to-nine train—it was simply disgraceful."

"i really don't know what you're talking about," said the duke quietly. "wasn't there a quarter-to-nine train?"

"of course there wasn't," said germaine. "the time-table was years old. i think it was the most senseless attempt at a joke i ever heard of."

"it doesn't seem to me to be a joke at all," said the duke quietly. "at any rate, it isn't the kind of a joke i make—it would be detestable. i never thought to look at the date of the time-table. i keep a box of cigarettes in that drawer, and i have noticed the time-table there. of course, it may have been lying there for years. it was stupid of me not to look at the date."

"i said it was a mistake. i was sure that his grace would not do anything so unkind as that," said sonia.

the duke smiled at her.

"well, all i can say is, it was very stupid of you not to look at the date," said germaine.

m. gournay-martin rose to his feet and wailed, in the most heartrending fashion: "my pictures! my wonderful pictures! such investments! and my cabinets! my renaissance cabinets! they can't be replaced! they were unique! they were worth a hundred and fifty thousand francs."

m. formery stepped forward with an air and said, "i am distressed, m. gournay-martin—truly distressed by your loss. i am m. formery, examining magistrate."

"it is a tragedy, m. formery—a tragedy!" groaned the millionaire.

"do not let it upset you too much. we shall find your masterpieces—we shall find them. only give us time," said m. formery in a tone of warm encouragement.

the face of the millionaire brightened a little.

"and, after all, you have the consolation, that the burglars did not get hold of the gem of your collection. they have not stolen the coronet of the princesse de lamballe," said m. formery.

"no," said the duke. "they have not touched this safe. it is unopened."

"what has that got to do with it?" growled the millionaire quickly. "that safe is empty."

"empty ... but your coronet?" cried the duke.

"good heavens! then they have stolen it," cried the millionaire hoarsely, in a panic-stricken voice.

"but they can't have—this safe hasn't been touched," said the duke.

"but the coronet never was in that safe. it was—have they entered my bedroom?" said the millionaire.

"no," said m. formery.

"they don't seem to have gone through any of the rooms except these two," said the duke.

"ah, then my mind is at rest about that. the safe in my bedroom has only two keys. here is one." he took a key from his waistcoat pocket and held it out to them. "and the other is in this safe."

the face of m. formery was lighted up with a splendid satisfaction. he might have rescued the coronet with his own hands. he cried triumphantly, "there, you see!"

"see? see?" cried the millionaire in a sudden bellow. "i see that they have robbed me—plundered me. oh, my pictures! my wonderful pictures! such investments!"