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 went up to the house, the 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... "

“We had a dreadful scene. She is a most loving woman, Mr. Holmes. If ever a woman loved a man with all her heart and soul, she loves me. She was cut to the heart that I should have discovered this horrible, this incredible, secret. She would not even speak. She gave no answer to my reproaches, save to gaze at me with a sort of wild, despairing look in her eyes. Then she rushed to her room and locked herself in. Since then she has refused to see me. She has a maid who was with her before her marriage, Dolores by name — a friend rather than a servant. She takes her food to her.”

“Then the child is in no immediate danger?”

“Mrs. Mason, the nurse, has sworn that she will not leave it night or day. I can absolutely trust her. I am more uneasy about poor little Jack, for, as I told you in my note, he has twice been assaulted by her.”

“But never wounded?”

“No, she struck him savagely. It is the more terrible as he is a poor little inoffensive cripple.” Ferguson’s gaunt features softened as he spoke of his boy. “You would think that the dear lad’s condition would soften anyone‘s heart. A fall in childhood and a twisted spine, Mr. Holmes. But the dearest, most loving heart within.”

Holmes had picked up the letter of yesterday and was reading it over. “What other inmates are there in your house, Mr. Ferguson?”

“Two servants who have not been long with us. One stablehand, Michael, who sleeps in the house. My wife, myself, my boy Jack, baby, Dolores, and Mrs. Mason. That is all.”

“I gather that you did not know your wife well at the time of your marriage?”

“I had only known her a few weeks.”

“How long had this maid Dolores been with her?”

“Some years.”

“Then your wife’s character would really be better known by Dolores than by you?”

“Yes, you may say so.”

Holmes made a note.

“I fancy,” said he, “that I may be of more use at Lamberley than here. It is eminently a case for personal investigation. If the lady remains in her room, our presence could not annoy or inconvenience her. Of course, we would stay at the inn.”

Ferguson gave a gesture of relief.

“It is what I hoped, Mr. Holmes. There is an excellent train at two from Victoria if you could come.”

“Of course we could come. There is a lull at present. I can give you my undivided energies. Watson, of course, comes with us. But there are one or two points upon which I wish to be very sure before I start. This unhappy lady, as I understand it, has appeared to assault both the children, her own baby and your little son?”

“That is so.”

“But the assaults take different forms, do they not? She has beaten your son.”

“Once with a stick and once very savagely with her hands.”

“Did she give no explanation why she struck him?”

“None save that she hated him. Again and again she said so.”