What Lupin felt most in the whole business was Daubrecq's revelation of the whereabouts of the flat. The police had entered his place in the Rue Chateaubriand. The identity of Lupin and Michel Beaumont had been recognized and certain papers discovered; and Lupin, while pursuing his aim, while, at the same time, managing various enterprises on which he had embarked, while avoiding the searches of the police, which were becoming more zealous and persistent than ever, had to set to work and reorganize his affairs throughout on a fresh basis.

His rage with Daubrecq, therefore, increased in proportion to the worry which the deputy caused him. He had but one longing, to pocket him, as he put it, to have him at his bidding by fair means or foul, to extract his secret from him. He dreamt of tortures fit to unloose the tongue of the most silent of men. The boot, the rack, red-hot pincers, nailed planks: no form of suffering, he thought, was more than the enemy deserved; and the end to be attained justified every means.

"Oh," he said to himself, "oh, for a decent bench of inquisitors and a couple of bold executioners!... What a time we should have!"

Every afternoon the Growler and and the Masher watched the road which Daubrecq took between the Square Lamartine, the Chamber of Deputies and his club. Their instructions were to choose the most deserted street and the most favourable moment and, one evening, to hustle him into a motor-car.

Lupin, on his side, got ready an old building, standing in the middle of a large garden, not far from Paris, which presented all the necessary conditions of safety and isolation and which he called the Monkey's Cage.

Unfortunately, Daubrecq must have suspected something, for every time, so to speak, he changed his route, or took the underground or a tram; and the cage remained unoccupied.

Lupin devised another plan. He sent to Marseilles for one of his associates, an elderly retired grocer called Brindebois, who happened to live in Daubrecq's electoral district and interested himself in politics. Old Brindebois wrote to Daubrecq from Marseilles, announcing his visit. Daubrecq gave this important constituent a hearty welcome, and a dinner was arranged for the following week.

The elector suggested a little restaurant on the left bank of the Seine, where the food, he said, was something wonderful. Daubrecq accepted.

This was what Lupin wanted. The proprietor of the restaurant was one of his friends. The attempt, which was to take place on the following Thursday, was this time bound to succeed.

Meanwhile, on the Monday of the same week, the trial of Gilbert and Vaucheray opened.

The reader will remember - and the case took place too recently for me to recapitulate its details - the really incomprehensible partiality which the presiding judge showed in his cross-examination of Gilbert. The thing was noticed and severely criticised at the time. Lupin recognized Daubrecq's hateful influence.

The attitude observed by the two prisoners differed greatiy. Vaucheray was gloomy, silent, hard-faced. He cynically, in curt, sneering, almost defiant phrases, admitted the crimes of which he had formerly been guilty. But, with an inconsistency which puzzled everybody except Lupin, he denied any participation in the murder of Leonard the valet and violently accused Gilbert. His object, in thus linking his fate with Gilbert's, was to force Lupin to take identical measures for the rescue of both his accomplices.

Holmes sat for some time in silent thought. He had lit the oldest and foulest of his pipes.

“I am not clear yet what you want me to do in this matter, Mr. Mason,” he said at last. “Can’t you make it more definite?”

“Perhaps this will make it more definite, Mr. Holmes,” said our visitor.

He took a paper from his pocket, and, unwrapping it carefully, he exposed a charred fragment of bone.

Holmes examined it with interest.

“Where did you get it?”

“There is a central heating furnace in the cellar under Lady Beatrice’s room. It‘s been off for some time, but Sir Robert complained of cold and had it on again.

Harvey runs it — he’s one of my lads. This very morning he came to me with this which he found raking out the cinders. He didn’t like the look of it.”

“Nor do I,” said Holmes. “What do you make of it, Watson?”

It was burned to a black cinder, but there could be no question as to its anatomical significance.

“It’s the upper condyle of a human femur,” said I.

“Exactly!” Holmes had become very serious. “When does this lad tend to the furnace?”

“He makes it up every evening and then leaves it.”

“Then anyone could visit it during the night?”

“Yes, sir.”

“Can you enter it from outside?”

“There is one door from outside. There is another which leads up by a stair to the passage in which Lady Beatrice’s room is situated.”

“These are deep waters, Mr. Mason; deep and rather dirty. You say that Sir Robert was not at home last night?”

“No, sir.”

“Then, whoever was burning bones, it was not he.”

“That’s true, sir.”

“What is the name of that inn you spoke of?”

“The Green Dragon.”

“Is there good fishing in that part of Berkshire?” The honest trainer showed very clearly upon his face that he was convinced that yet another lunatic had come into his harassed life.

“Well, sir, I’ve heard there are trout in the mill-stream and pike in the Hall lake.”

“That’s good enough. Watson and I are famous fishermen — are we not, Watson? You may address us in future at the Green Dragon. We should reach it to-night. I need not say that we don’t want to see you, Mr. Mason, but a note will reach us, and no doubt I could find you if I want you. When we have gone a little farther into the matter I will let you have a considered opinion.”

Thus it was that on a bright May evening Holmes and I found ourselves alone in a first-class carriage and bound for the little “halt-on-demand” station of Shoscombe. The rack above us was covered with a formidable litter of rods, reels, and baskets. On reaching our destination a short drive took us to an old-fashioned tavern, where a sporting host, Josiah Barnes, entered eagerly into our plans for the extirpation of the fish of the neighbourhood.