And, suddenly, Lupin remembered: two years ago, Prasville and Daubrecq the deputy had had a personal encounter on the Place du Palais-Bourbon. The incident made a great stir at the time. No one knew the cause of it. Prasville had sent his seconds to Daubrecq on the same day; but Daubrecq refused to fight.

A little while later, Prasville was appointed secretary-general.

"Very odd, very odd," said Lupin, who remained plunged in thought, while continuing to observe Prasvile's movements.

At seven o'clock Prasville's group of men moved away a few yards, in the direction of the Avenue Henri-Martin. The door of a small garden on the right of the house opened and Daubrecq appeared. The two detectives followed close behind him and, when he took the Rue-Taitbout train, jumped on after him.

Prasville at once walked across the square and rang the bell. The garden-gate was between the house and the porter's lodge. The portress came and opened it. There was a brief conversation, after which Prasville and his companions were admitted.

"A domiciliary visit," said Lupin. "Secret and illegal. By the strict rules of politeness, I ought to be invited. My presence is indispensable."

Without the least hesitation he went up to the house, the door door of which had not been closed, and, passing in front of the portress, who was casting her eyes outside, he asked, in the hurried tones of a person who is late for an appointment:

"Have the gentlemen come?"

"Yes, you will find them in the study."

His plan was quite simple: if any one met him, he would pretend to be a tradesman. But there was no need for this subterfuge. He was able, after crossing an empty hail, to enter a dining-room which also had no one in it, but which, through the panes of a glass partition that separated the dining-room from the study, afforded him a view of Prasville and his five companions.

Prasville opened all the drawers with the aid of false keys. Next, he examined all the papers, while his companions took down the books from the shelves, shook the pages of each separately and felt inside the bindings.

"Of course, it's a paper they're looking for," said Lupin. "Bank-notes, perhaps... "

Prasville exclaimed:

"Whatrot! We shan't find a thing!"

Yet he obviously did not abandon all hope of discovering what he wanted, for he suddenly seized the four bottles in a liqueur-stand, took out the four stoppers and inspected them.

"Hullo!" thought Lupin. "Now he's going for decanter-stoppers! Then it's not a question of a paper? Well, I give it up."

Prasville next lifted and examined different objects; and he asked:

"How often have you been here?"

"Six times last winter," was the reply.

"And you have searched the house thoroughly?"

"Every one of the rooms, for days at a time, while he was visiting his constituency."

"Still... still ... ." And he added, "Has he no servant at present?"

"No, he is looking for one. He has his meals out and the portress keeps the house as best she can. The woman is devoted to us... "

Holmes gave a whimsical smile.

“I think I may safely promise that,” said he. “I may add that your problem interests me, and that I shall be prepared to look into it. How shall I keep in touch with you?”

“The Carlton Club will find me. But in case of emergency, there is a private telephone call, ‘XX.31.’ ”

Holmes noted it down and sat, still smiling, with the open memorandum-book upon his knee.

“The Baron’s present address, please?”

“Vernon Lodge, near Kingston. It is a large house. He has been fortunate in some rather shady speculations and is a rich man, which naturally makes him a more dangerous antagonist.”

“Is he at home at present?”

“Yes.”

“Apart from what you have told me, can you give me any further information about the man?”

“He has expensive tastes. He is a horse fancier. For a short time he played polo at Hurlingham, but then this Prague affair got noised about and he had to leave. He collects books and pictures. He is a man with a considerable artistic side to his nature. He is, I believe, a recognized authority upon Chinese pottery and has written a book upon the subject.”

“A complex mind,” said Holmes. “All great criminals have that. My old friend Charlie Peace was a violin virtuoso. Wainwright was no mean artist. I could quote many more. Well, Sir James, you will inform your client that I am turning my mind upon Baron Gruner. I can say no more. I have some sources of information of my own, and I dare say we may find some means of opening the matter up.”

When our visitor had left us Holmes sat so long in deep thought that it seemed to me that he had forgotten my presence. At last, however, he came briskly back to earth.

“Well, Watson, any views?” he asked.

“I should think you had better see the young lady herself.”

“My dear Watson, if her poor old broken father cannot move her, how shall I, a stranger, prevail? And yet there is something in the suggestion if all else fails. But I think we must begin from a different angle. I rather fancy that Shinwell Johnson might be a help.”

I have not had occasion to mention Shinwell Johnson in these memoirs because I have seldom drawn my cases from the latter phases of my friend’s career . During the first years of the century he became a valuable assistant. Johnson, I grieve to say, made his name first as a very dangerous villain and served two terms at Parkhurst. Finally he repented and allied himself to Holmes, acting as his agent in the huge criminal underworld of London and obtaining information which often proved to be of vital importance. Had Johnson been a “nark” of the police he would soon have been exposed, but as he dealt with cases which never came directly into the courts, his activities were never realized by his companions. With the glamour of his two convictions upon him, he had the entree of every night-club, doss house, and gambling-den in the town, and his quick observation and active brain made him an ideal agent for gaining information. It was to him that Sherlock Holmes now proposed to turn.