Lord St. Simon shrugged his shoulders and raised his eyebrows. “We have been on a friendly footing for some years -I may say on a very friendly footing. She used to be at the Allegro. I have not treated her ungenerously, and she had no just cause of complaint against me, but you know what women are, Mr. Holmes. Flora was a dear little thing, but exceedingly hot-headed and devotedly attached to me. She wrote me dreadful letters when she heard that I was about to be married, and, to tell the truth, the reason why I had the marriage celebrated so quietly was that I feared lest there might be a scandal in the church. She came to Mr. Doran’s door just after we returned, and she endeavoured to push her way in, uttering very abusive expressions towards my wife, and even threatening her, but I had foreseen the possibility of something of the sort, and I had two police fellows there in private clothes, who soon pushed her out again. She was quiet when she saw that there was no good in making a row.”

“Did your wife hear all this?”

“No, thank goodness, she did not.”

“And she was seen walking with this very woman afterwards?”

“Yes. That is what Mr. Lestrade, of Scotland Yard, looks upon as so serious. It is thought that Flora decoyed my wife out and laid some terrible trap for her.”

“Well, it is a possible supposition.”

“You think so, too?”

“I did not say a probable one. But you do not yourself look upon this as likely?”

“I do not think Flora would hurt a fly.”

“Still, jealousy is a strange transformer of characters. Pray what is your own theory as to what took place?”

“Well, really, I came to seek a theory, not to propound one. I have given you all the facts. Since you ask me, however, I may say that it has occurred to me as possible that the excitement of this affair, the consciousness that she had made so immense a social stride, had the effect of causing some little nervous disturbance in my wife.”

“In short, that she had become suddenly deranged?”

“Well, really, when I consider that she has turned her back -I will not say upon me, but upon so much that many have aspired to without success -I can hardly explain it in any other fashion.”

“Well, certainly that is also a conceivable hypothesis,” said Holmes, smiling. “And now, Lord St. Simon, I think that I have nearly all my data. May I ask whether you were seated at the breakfast-table so that you could see out of the window?”

“We could see the other side of the road and the Park.”

“Quite so. Then I do not think that I need to detain you longer. I shall communicate with you.”

“Should you be fortunate enough to solve this problem,” said our client, rising.

“I have solved it.”

“Eh? What was that?”

“I say that I have solved it.”

“Where, then, is my wife?”

“That is a detail which I shall speedily supply.”

Lord St. Simon shook his head. “I am afraid that it will take wiser heads than yours or mine,” he remarked, and bowing in a stately, old-fashioned manner he departed.

“It is very good of Lord St. Simon to honour my head by putting it on a level with his own,” said Sherlock Holmes, laughing. “I think that I shall have a whisky and soda and a cigar after all this cross-questioning. I had formed my conclusions as to the case before our client came into the room.”

“My dear Holmes!”

“I have notes of several similar cases, though none, as I remarked before, which were quite as prompt. My whole examination served to turn my conjecture into a certainty. Circumstantial evidence is occasionally very convincing, as when you find a trout in the milk, to quote Thoreau’s example.”

“But I have heard all that you have heard.”