We did not have long to wait. It was only a few minutes when Kennedy's surmise proved correct. Miss Golder and Dr. Goode came out, and turned in the direction of the railroad station for Norwood. He was eagerly questioning her about something, perhaps, I imagined, our visit to Dr.

Loeb. What did it mean?

There was no use and it was too risky to follow them. Kennedy turned and we made our way uptown to the laboratory, where he plunged at once into an examination of the blood specimens he had taken from the Moretons and of the peculiar porcelain cone which he had picked up in the rubbish pile between the two houses.

Having emptied the specimens of blood in several little shallow gla.s.s receptacles which he covered with black paper and some very sensitive films, he turned his attention to the cone. I noted that he was very particular in his examination of it, apparently being very careful to separate whatever it was he was looking for on the inside and the outside surfaces.

"That," he explained to me at length as he worked, "is what is known as a Berkefeld filter, a little porous cup, made of porcelain. The minute meshes of this filter catch and hold bacteria as if in the meshes of a microscopic sieve, just like an ordinary water filter. It is so fine that it holds back even the tiny bacillus fluorescens liquefaciens which are used to test it. These bacilli measure only from a half to one and one-and-a-half micromillimeters in diameter. In other words 130,000 germs of half a micromillimeter would be necessary to make an inch."

"What has it been used for?" I ventured.

"I can't say, yet," he returned, and I did not pursue the inquiry, knowing Kennedy's aversion to being questioned when he was not yet sure of his facts.

It was the next day when the post-office inspectors, the police and others who had been co-operating had settled on the raid not only of Dr.

Loeb's but of all the medical quacks who were fleecing the credulous of the city out of hundreds of thousands of dollars a year by one of the most cruel swindles that have ever been devised.

For the time, Kennedy dropped his investigations in the laboratory and we went down to O'Hanlon's office, where a thick batch of warrants, just signed, had been received.

Quickly O'Hanlon disposed his forces so that in all parts of the town they might swoop down at once and gather in the medical harpies. Dr.

Loeb's stood first on the list of those which O'Hanlon decided to handle himself.

"By the way," mentioned O'Hanlon as we hurried uptown to be ready in time, "I had a letter from Darius Moreton this morning threatening me with all kinds of trouble unless we let up on Dr. Loeb. It's pretty hard to keep a big investigation like this secret, but I think we've planned a little surprise for this morning."

With the post-office inspector we climbed into a patrol wagon with a detail of police who were to make a general round-up of the places on Forty-second Street.

As the wagon backed up to the curb in front of the building in which Loeb's office was, the policemen hopped out and hurried into the building before a crowd could collect. Unceremoniously they rushed through the outer office, headed by O'Hanlon.

Quickly though the raid was executed, it could not be done without some warning commotion. As we entered the front door of the office, we could just catch a glimpse of a man retreating through a back door. There was something familiar about his back, and Kennedy and I started after him.

But we were too late. He had fled without even waiting for his hat, which lay on Miss Golder's desk, and had disappeared down a back stairway which had been left unguarded.

"Confound it," muttered O'Hanlon, as we returned, "Loeb hasn't been here today. Who was that?"

"I don't know," replied Craig, picking up the hat, underneath which lay a package.

He opened the package. Inside were half a dozen Berkefeld filters, those peculiar porcelain cones such as we had found out at Norwood.

Quickly Craig ran his eye over the ma.s.s of papers on Miss Golder's desk.

He picked up an appointment book and turned the pages rapidly. There were several entries that seemed to interest him. I bent over. Among other names entered during the past few days I made out both "Moreton"

and "Dr. Goode." I recalled the letter which O'Hanlon had received from Moreton. Had he or someone else got wind of the raids and tipped off Dr.

Loeb?

Above the hubbub of the raid I could hear O'Hanlon putting poor little Miss Golder through a third degree.

"Who was it that went out?" he shouted into her face. "You might as well tell. If you don't it'll go hard with you."

But, like all women who have been taken into these get-rich-quick swindles, she was loyal to a fault. "I don't know," she sobbed, dabbing at her eyes with a bit of a lace handkerchief.

Nor could all of O'Hanlon's bulldozing get another admission out of her except that it was a "stranger." She protested and wept. But she even rode off in the patrol wagon with the rest of the employes unmoved.

Whom was she shielding? All we had was the secretary, a couple of cappers, and half a dozen patients, regular and prospective, who had been waiting in the office. We had a wagon-load of evidence, including letters and circulars, apparatus of all kinds, medicines, and pills. But there was nothing more. Craig did not seem especially interested in the ma.s.s of stuff which the police had seized.

In fact the only thing that seemed to interest him was the man who had disappeared. We had his hat and the package of filters. Craig picked up the hat and examined it.

"It's a soft hat and consequently doesn't tell us very much about the shape of his head," he remarked. Then his face brightened. "But he couldn't have left anything much better," he remarked complacently, as he went over to one of the little wall cabinets which the towel service companies place over wash-basins in offices. He took from it a comb and brush and wrapped them up carefully.

I looked at the hat also. There was no name in it, not even the usual initials. What did Craig mean?

Other raids in various parts of the city proved far more successful than the one in which we had partic.i.p.ated and O'Hanlon quickly forgot his chagrin in the reports that soon came piling in. As for ourselves we had no further interest except in the disposition of this case, and Craig decided shortly to go back to work again in the laboratory among his test-tubes, slides, and microscopes.

"I will leave you to follow the cases against the quacks, particularly Dr. Loeb and Miss Golder, Walter," he said. "By the way, you saw me take that hair brush. I wish I had a collection of them. In some way you must get me a hair brush from Dr. Goode. You'll have to take a trip out to Norwood. And while you are there, get the brushes from Darius Moreton and Lionel. I don't know how you'll get Goode's, but Myra will help you with the others, I'm sure."

He turned to his work and was soon absorbed in some microscopic studies, leaving me no chance to question him about his strange commission.

CHAPTER x.x.x

THE FILTERABLE VIRUS

I was surprised to run into O'Hanlon himself in the train out to Norwood. The failure to get Dr. Loeb troubled him and he had reasoned that if Darius Moreton took the trouble to write a letter about his friend he might possibly know more of his whereabouts than he professed.

We discussed the case nearly the whole journey, agreeing to separate just before we reached the station in order not to be seen together.

It took me longer to carry out Kennedy's request than I had expected. I found Myra at home alone, very much excited.

"Someone called me up from New York this morning," she said, "and asked whether father and Lionel were at home. I thought they were at the factory, but when I called there, the foreman told me they hadn't been there. And Dr. Goode is out, too--hasn't seen any of his patients today.

Oh, Mr. Jameson, what does it all mean? Where have they gone?"

I was a poor one to comfort her, for I had no idea myself. Still, I did my best, and incidentally secured the brushes, though I must confess I had to commit a little second-story work to get into Dr. Goode's.

It seemed heartless to leave the poor girl all alone, but I knew that Kennedy was waiting anxiously for me. I promised to make inquiries all over about her father, Lionel, and Dr. Goode, and, I think, the mere fact that someone showed an interest in her cheered her up, especially when I told her Kennedy was working hard on the case.

As I waited for the train that was to take me back to the city, the train from New York pulled in. Imagine my surprise when I saw Miss Golder step off nervously and hurry up the main street.

I watched her, debating what to do, whether to let Kennedy wait and follow her, or not.

"Someone, they don't know who, bailed her out," I heard a voice whisper in my ear.

I turned quickly. It was O'Hanlon. "She put up cash bail," he added under his breath. "No one knows where she got it. I'm waiting until she turns that corner--then I'm going to shadow her. I can't seem to find anyone in this town just now. Perhaps she knows where Loeb is."

"If you get on the trail, will you wire me?" I asked. "Here's my train now."

O'Hanlon promised, and as I swung on the step I caught a last glimpse of him sauntering casually in the direction Miss Golder had taken.

I handed Kennedy the brushes I had obtained, but he gave me no opportunity to satisfy my curiosity. Instead, he started me out again to keep in touch with the progress made in the cases of the quacks, particularly the search for Dr. Loeb, which seemed to interest him quite as much as the bailing out of Miss Golder.

It was after dinner and I was preparing to follow the cases on into the night court, if necessary, when one of O'Hanlon's a.s.sistants hurried up to me.