"You--you don't think it is serious?" whispered Betty in an undertone, scarcely waiting to be introduced. She had evidently known of our visit, but had been unable to get away to be present upstairs.

"Really, Miss Blake," rea.s.sured Kennedy, "I can't say. All I can do is to repeat what I have already said to your mother. Keep up a good heart and trust me to work it out."

"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."

"What are you doing in this case?" asked Kennedy.

"What the insurance companies have to do to recover stolen automobiles," Garwood replied. "For, with all deference to your friend, Deputy O'Connor, it is the insurance companies rather than the police who get stolen cars back."

He had pulled out a postal card from a pigeon hole in his desk, selecting it from several apparently similar. We read:

$250.00 REWARD

We will pay $100.00 for car, $150.00 additional for information which will convict the thief. When last seen, driven by a woman, name not known, who is described as dark-haired, well-dressed, slight, apparently thirty years old. The car is a Dixon, 1912, seven-pa.s.senger, touring, No. 193,222, license No. 200,859, New York; dark red body, mohair top, bra.s.s lamps, has no wind shield; rear axle brake band device has extra nut on turnbuckle not painted. Car last seen near Prince Henry Hotel, New York City, Friday, the 10th.

Communicate by telegraph or telephone, after notifying nearest police department, with Douglas Garwood, New York City. "The secret of it is,"

explained Garwood, as we finished reading, "that there are innumerable people who keep their eyes open and like to earn money easily. Thus we have several hundreds of amateur and enthusiastic detectives watching all over the city and country for any car that looks suspicious."

Kennedy thanked him for his courtesy, and we rose to go. "I shall be glad to keep you informed of anything that turns up," he promised.

CHAPTER XX

THE ARTIFICIAL KIDNEY

In the laboratory, Kennedy quietly set to work. He began by tearing from the germ letter the piece of gelatine and first examining it with a pocket lens. Then, with a sterile platinum wire, he picked out several minute sections of the black spot on the gelatine and placed them in agar, blood serum, and other media on which they would be likely to grow.

"I shall have to wait until to-morrow to examine them properly," he remarked. "There are colonies of something there, all right, but I must have them more fully developed."

A hurried telephone call late in the day from Miss Sears told us that Mrs. Blake herself had begun to complain, and that Dr. Wilson had been summoned but had been unable to give an opinion on the nature of the malady.

Kennedy quickly decided on making a visit to the doctor, who lived not far downtown from the laboratory.

Dr. Rae Wilson proved to be a nervous little woman, inclined, I felt, to be dictatorial. I thought that secretly she felt a little piqued at our having been taken into the Blakes' confidence before herself, and Kennedy made every effort to smooth that aspect over tactfully.

"Have you any idea what it can be?" he asked finally.

She shook her head noncommittally. "I have taken blood smears," she answered, "but so far haven't been able to discover anything. I shall have to have her under observation for a day or two before I can answer that. Still, as Mrs. Blake is so ill, I have ordered another trained nurse to relieve Miss Sears of the added work, a very efficient nurse, a Miss Rogers."

Kennedy had risen to go. "You have had no word about your car?" he asked casually.

"None yet. I'm not worrying. It was insured."

"Who is this arch criminal, Dr. Hopf?" I mused as we retraced our steps to the laboratory. "Is Mrs. Blake stricken now by the same trouble that seems to have affected Buster?"

"Only my examination will show," he said. "I shall let nothing interfere with that now. It must be the starting point for any work that I may do in the case."

We arrived at Kennedy's workshop of scientific crime and he immediately plunged into work. Looking up he caught sight of me standing helplessly idle.

"Walter," he remarked thoughtfully adjusting a microscope, "suppose you run down and see Garwood. Perhaps he has something to report. And by the way, while you are out, make inquiries about the Blakes, young Baldwin, Miss Sears and this Dr. Wilson. I have heard of her before, at least by name. Perhaps you may find something interesting."

Glad to have a chance to seem to be doing something whether it amounted to anything or not, I dropped in to see Garwood. So far he had nothing to report except the usual number of false alarms. From his office I went up to the Star where fortunately I found one of the reporters who wrote society notes.

The Blakes, I found, as we already knew, to be well known and moving in the highest social circles. As far as known they had no particular enemies, other than those common to all people of great wealth. Dr.

Wilson had a large practice, built up in recent years, and was one of the best known society physicians for women. Miss Sears was unknown, as far as I could determine. As for Duncan Baldwin, I found that he had become acquainted with Reginald Blake in college, that he came of no particular family and seemed to have no great means, although he was very popular in the best circles. In fact he had had, thanks to his friend, a rather meteoric rise in society, though it was reported that he was somewhat involved in debt as a result.

I returned to the laboratory to find that Craig had taken out of a cabinet a peculiar looking arrangement. It consisted of thirty-two tubes, each about sixteen inches long, with S-turns, like a minute radiator. It was altogether not over a cubic foot in size, and enclosed in a gla.s.s cylinder. There were in it, perhaps, fifty feet of tubes, a perfectly-closed tubular system which I noticed Kennedy was keeping absolutely sterile in a germicidal solution of some kind.

Inside the tubes and surrounding them was a saline solution which was kept at a uniform temperature by a special heating apparatus.