xecute the warrant."

Whiteside agreed.

"It is quite impossible that she could have committed the murder," he
said. "I suppose the doctor's evidence is unshakable?"

"Absolutely," said Tarling, "and it is confirmed by the station master
at Ashford, who has the time of the accident logged in his diary, and
himself assisted to lift the girl from the train."

"Why did she call herself Miss Stevens?" asked Whiteside. "And what
induced her to leave London so hurriedly?"

Tarling gave a despairing gesture.

"That is one of the things I should like to know," he said, "and the very
matter upon which Miss Rider refuses to enlighten me. I am taking her to
an hotel," he went on. "To-morrow I will bring her down to the Yard. But
I doubt if the Chief can say anything that will induce her to talk."

"Was she surprised when you told her of the murder? Did she mention
anybody's name?" asked Whiteside.

Tarling hesitated, and then, for one of the few times in his life, he
lied.

"No," he said, "she was just upset ... she mentioned nobody."

He took the girl by taxi to the quiet little hotel he had chosen--a
journey not without its thrills, for the fog was now thick--and saw her
comfortably fixed.

"I can't be sufficiently grateful to you, Mr. Tarling, for your
kindness," she said at parting "and if I could make your task any
easier ... I would."

He saw a spasm of pain pass across her face.

"I don't understand it yet; it seems like a bad dream," she said half to
herself. "I don't want to understand it somehow ... I want to forget, I
want to forget!"

"What do you want to forget?" asked Tarling.

She shook her head.

"Don't ask me," she said. "Please, please, don't ask me!"

He walked down the big stairway, a greatly worried man. He had left the
taxi at the door. To his surprise he found the cab had gone, and turned
to the porter.

"What happened to my taxi?" he said. "I didn't pay him off."

"Your taxi, sir?" said the head porter. "I didn't see it go. I'll ask one
of the boys."

As assistant porter who had been in the street told a surprising tale. A
gentleman had come up out of the murk, had paid off the taxi, which had
disappeared. The witness to this proceeding had not seen the gentleman's
face. All he knew was that this mysterious benefactor had walked away in
an opposite direction to that in which the cab had gone, and had vanished
into the night.

Tarling frowned.

"That's curious," he said. "Get me