The specialist smiled grimly. He snatched up a book from a pile on the table, thrust open the title-page and held it out.

"Read that, sir.... As it happens, it's my hobby. Go and ask Dr. Foster, if you like.... No, sir; I must have your friend; it's a good sound case."

The Major read the title-page in a superior manner. It purported to be by a James Whitty, and the name was followed by a series of distinctions and of the initials, which I have forgotten. F.R.S. were the first.

"My name," said the doctor.

The Major handed the book back with a bow.

"I am proud to make your acquaintance, Dr. Whitty. I have heard of you. May I present Mrs. Trustcott?"

Gertie looked confused. The doctor made a stiff obeisance. Then his face became animated again.

"We must move your friend upstairs," he said. "If you will help, Mr. Trustcott, I will call my servant."

(III)

It was about half-past nine that night that the doctor, having rung the bell in the spare bedroom, met his man at the threshold.