"Still," said Mr. Marchmont, "the fact is that he did get in, and that he is not here now; and therefore he must have got out; and therefore it must have been possible for him to get out. And, further, it must be possible to discover how he got out."
The inspector smiled sourly, but made no reply.
"The circumstances," said Thorndyke, "appear to have been these: The deceased seems to have been alone; there is no trace of a second occupant of the room, and only one half-emptied tumbler on the table. He was sitting reading when apparently he noticed that the clock had stopped--at ten minutes to twelve; he laid his book, face downwards, on the table, and rose to wind the clock, and as he was winding it he met his death."
"By a stab dealt by a left-handed man, who crept up behind him on tiptoe," added the inspector.
Thorndyke nodded. "That would seem to be so," he said. "But now let us call in the porter, and hear what he has to tell us."
The custodian was not difficult to find, being, in fact, engaged at that moment in a survey of the premises through the slit of the letter-box.
"Do you know what persons visited these rooms last night?" Thorndyke asked him, when he entered looking somewhat sheepish.
"A good many were in and out of the building," was the answer, "but I can't say if any of them came to this flat. I saw Miss Curtis pass in about nine."
"My daughter!" exclaimed Mr. Curtis, with a start. "I didn't know that."
"She left about nine-thirty," the porter added.
"Do you know what she came about?" asked the inspector.
"Then don't say," interrupted Mr. Marchmont. "Answer no questions."
"You're very close, Mr. Marchmont," said the inspector; "we are not suspecting the young lady. We don't ask, for instance, if she is left-handed."
He glanced craftily at Mr. Curtis as he made this remark, and I noticed that our client suddenly turned deathly pale, whereupon the inspector looked away again quickly, as though he had not observed the change.
"Tell us about those Italians again," he said, addressing the porter. "When did the first of them come here?"
"About a week ago," was the reply. "He was a common-looking man--looked like an organ-grinder--and he brought a note to my lodge. It was in a dirty envelope, and was addressed 'Mr. Hartridge, Esq., Brackenhurst Mansions,' in a very bad handwriting. The man gave me the note and asked me to give it to Mr. Hartridge; then he went away, and I took the note up and dropped it into the letter-box."