"And arrest Milburgh," suggested Whiteside. "Do you accept Ling Chu's theory?"
Tarling shook his head.
"I am loath to reject it," he said, "because he is the most amazingly clever tracker. He can trace footmarks which are absolutely invisible to the eye, and he has a bushman's instinct which in the old days in China led to some extraordinary results."
They returned to town by car, Ling Chu riding beside the chauffeur, smoking an interminable chain of cigarettes. Tarling spoke very little during the journey, his mind being fully occupied with the latest development of a mystery, the solution of which still evaded him.
The route through London to Scotland Yard carried him through Cavendish Place, where the nursing home was situated in which Odette Rider lay. He stopped the car to make inquiries, and found that the girl had recovered from the frenzy of grief into which the terrible discovery of the morning had thrown her, and had fallen into a quiet sleep.
"That's good news, anyway," he said, rejoining his companion. "I was half beside myself with anxiety."
"You take a tremendous interest in Miss Rider, don't you?" asked Whiteside dryly.
Tarling brindled, then laughed.
"Oh, yes, I take an interest," he admitted, "but it is very natural."
"Why natural?" asked Whiteside.