“Thank you,” she murmured, and then, impulsively extending her small hand to Craig, she added, “Mr. Kennedy, if there is anything I can do to help you, I beg that you will call on me.”

“I shall not forget,” he answered, relinquishing the hand reluctantly.  Then, as she thanked him, and turned again to her guest, he added in a low tone to me, “A remarkable girl, Walter, a girl that can be depended on.”

We followed Miss Sears down the hall.

“Who was that young man in the music room?” asked Kennedy, when we were out of earshot.

“Duncan Baldwin,” she answered.  “A friend and bosom companion of Reginald.”

“He seems to think more of Betty than of her brother,” Craig remarked dryly.

Miss Sears smiled.  “Sometimes, we think they are secretly engaged,” she returned.  We had almost reached the door.  “By the way,” she asked anxiously, “do you think there are any precautions that I should take for Mrs. Blake—­and the rest?”

“Hardly,” answered Kennedy, after a moment’s consideration, “as long as you have taken none in particular already.  Still, I suppose it will do no harm to be as antiseptic as possible.”

“I shall try,” she promised, her face showing that she considered the affair now in a much more serious light than she had before our visit.

“And keep me informed of anything that turns up,” added Kennedy handing her a card with the telephone number of the laboratory.

As we left the Blake mansion, Kennedy remarked, “We must trace that car somehow—­at least we must get someone working on that.”

Half an hour later we were in a towering office building on Liberty Street, the home of various kinds of insurance.  Kennedy stopped before a door which bore the name, “Douglas Garwood:  Insurance Adjuster.”

Briefly, Craig told the story of the stolen car, omitting the account of the dastardly method taken to blackmail Mrs. Blake.  As he proceeded a light seemed to break on the face of Garwood, a heavyset man, whose very gaze was inquisitorial.

“Yes, the theft has been reported to us already by Dr. Wilson herself,” he interrupted.  “The car was insured in a company I represent.”

“I had hoped so,” remarked Kennedy, “Do you know the woman?” he added, watching the insurance adjuster who had been listening intently as he told about the fair motor car thief.

“Know her?” repeated Garwood emphatically.  “Why, man, we have been so close to that woman that I feel almost intimate with her.  The descriptions are those of a lady, well-dressed, and with a voice and manner that would carry her through any of the fashionable hotels, perhaps into society itself.”

“One of a gang of blackmailers, then,” I hazarded.

Garwood shrugged his shoulders.  “Perhaps,” he acquiesced.  “It is automobile thieving that interests me, though.  Why,” he went on, rising excitedly, “the gangs of these thieves are getting away with half a million dollars’ worth of high-priced cars every year.  The police seem to be powerless to stop it.  We appeal to them, but with no result.  So, now we have taken things into our own hands.”