CHAPTER XX
THE ARTIFICIAL KIDNEY
In the laboratory, Kennedy quietly set to work. He began by tearingfrom the germ letter the piece of gelatine and first examining it witha pocket lens. Then, with a sterile platinum wire, he picked outseveral minute sections of the black spot on the gelatine and placedthem in agar, blood serum, and other media on which they would belikely to grow.
"I shall have to wait until to-morrow to examine them properly," heremarked. "There are colonies of something there, all right, but I musthave them more fully developed."
A hurried telephone call late in the day from Miss Sears told us thatMrs. Blake herself had begun to complain, and that Dr. Wilson had beensummoned but had been unable to give an opinion on the nature of themalady.
Kennedy quickly decided on making a visit to the doctor, who lived notfar 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 atour having been taken into the Blakes' confidence before herself, andKennedy 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," sheanswered, "but so far haven't been able to discover anything. I shallhave to have her under observation for a day or two before I can answerthat. Still, as Mrs. Blake is so ill, I have ordered another trainednurse 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?" heasked casually.
"None yet. I'm not worrying. It was insured."
"Who is this arch criminal, Dr. Hopf?" I mused as we retraced our stepsto the laboratory. "Is Mrs. Blake stricken now by the same trouble thatseems to have affected Buster?"
"Only my examination will show," he said. "I shall let nothinginterfere with that now. It must be the starting point for any workthat I may do in the case."
We arrived at Kennedy's workshop of scientific crime and he immediatelyplunged into work. Looking up he caught sight of me standing helplesslyidle.
"Walter," he remarked thoughtfully adjusting a microscope, "suppose yourun down and see Garwood. Perhaps he has something to report. And bythe way, while you are out, make inquiries about the Blakes, youngBaldwin, Miss Sears and this Dr. Wilson. I have heard of her before, atleast by name. Perhaps you may find something interesting."
Glad to have a chance to seem to be doing something whether it amountedto anything or not, I dropped in to see Garwood. So far he had nothingto report except the usual number of false alarms. From his office Iwent up to the Star where fortunately I found one of the reporters whowrote society notes.
The Blakes, I found, as we already knew, to be well known and moving inthe highest social circles. As far as known they had no particularenemies, other than those common to all people of great wealth. Dr.Wilson had a large practice, built up in recent years, and was one ofthe best known society physicians for women. Miss Sears was unknown, asfar as I could determine. As for Duncan Baldwin, I found that he hadbecome acquainted with Reginald Blake in college, that he came of noparticular family and seemed to have no great means, although he wasvery popular in the best circles. In fact he had had, thanks to hisfriend, a rather meteoric rise in society, though it was reported thathe was somewhat involved in debt as a result.
I returned to the laboratory to find that Craig had taken out of acabinet a peculiar looking arrangement. It consisted of thirty-twotubes, each about sixteen inches long, with S-turns, like a minuteradiator. It was altogether not over a cubic foot in size, and enclosedin a glass cylinder. There were in it, perhaps, fifty feet of tubes, aperfectly-closed tubular system which I noticed Kennedy was keepingabsolutely sterile in a germicidal solution of some kind.
Inside the tubes and surrounding them was a saline solution which waskept at a uniform temperature by a special heating apparatus.
Kennedy had placed the apparatus on the laboratory table and thengently took the little dog from his basket and laid him beside it. Afew minutes later the poor little suffering Buster was mercifully underthe influence of an anesthetic.
Quickly Craig worked. First he attached the end of one of the tubes bymeans of a little cannula to the carotid artery of the dog. Then theother was attached to the jugular vein.
As he released the clamp which held the artery, the little dog'sfeverishly beating heart spurted the arterial blood from the carotidinto the tubes holding the normal salt solution and that pressure, inturn, pumped the salt solution which filled the tubes into the jugularvein, thus replacing the arterial blood that had poured into the tubesfrom the other end and maintaining the normal hydrostatic conditions inthe body circulation. The dog was being kept alive, although perhaps athird of his blood was out of his body.
"You see," he said at length, after we had watched the process a fewminutes, "what I have here is in reality an artificial kidney. It is asystem that has been devised by several doctors at Johns Hopkins.
"If there is any toxin in the blood of this dog, the kidneys arenaturally endeavoring to eliminate it. Perhaps it is being eliminatedtoo slowly. In that case this arrangement which I have here will aidthem. We call it vividiffusion and it depends for its action on thephysical principle of osmosis, the passage of substances of a certainkind through a porous membrane, such as these tubes of celloidin.
"Thus any substance, any poison that is dialyzable is diffused into thesurrounding salt solution and the blood is passed back into the body,with no air in it, no infection, and without alteration. Clotting isprevented by the injection of a harmless substance derived fromleeches, known as hirudin. I prevent the loss of anything in the bloodwhich I want retained by placing in the salt solution around the tubesan amount of that substance equal to that held in solution by theblood. Of course that does not apply to the colloidal substances in theblood which would not pass by osmosis under any circumstances. But bysuch adjustments I can remove and study any desired substance in theblood, provided it is capable of diffusion. In fact this littleapparatus has been found in practice to compare favorably with thekidneys themselves in removing even a lethal dose of poison."
I watched in amazement. He was actually cleaning the blood of the dogand putting it back again, purified, into the little body. Far frombeing cruel, as perhaps it might seem, it was in reality probably theonly method by which the animal could be saved, and at the same time itwas giving us a clue as to some elusive, subtle substance used in thecase.
"Indeed," Kennedy went on reflectively, "this process can be kept upfor several hours without injury to the dog, though I do not think thatwill be necessary to relieve the unwonted strain that has been put uponhis natural organs. Finally, at the close of the operation, seriousloss of blood is overcome by driving back the greater part of it intohis body, closing up the artery and vein, and taking good care of theanimal so that he will make a quick recovery."
For a long time I watched the fascinating process of seeing the lifeblood coursing through the porous tubes in the salt solution, whileKennedy gave his undivided attention to the success of the delicateexperiment. It was late when I left him, still at work over Buster, andwent up to our apartment to turn in, convinced that nothing more wouldhappen that night.
The next morning, with characteristic energy, Craig was at work early,examining the cultures he had made from the black spots on the gelatine.
By the look of perplexity on his face, I knew that he had discoveredsomething that instead of clearing the mystery up, further deepened it.
"What do you find?" I asked anxiously.
"Walter," he exclaimed, laying aside the last of the slides which hehad been staining and looking at intently through the microscope, "thatstuff on the gelatine is entirely harmless. There was nothing in itexcept common mold."
For the moment I did not comprehend. "Mold?" I repeated.
"Yes," he replied, "just
common, ordinary mold such as grows on the topof a jar of fruit or preserves when it is exposed to the air."
I stifled an exclamation of incredulity. It seemed impossible that thedeadly germ note should be harmless, in view of the events that hadfollowed its receipt.
Just then the laboratory door was flung open and Reginald Blake, paleand excited, entered. He had every mark of having been up all night.
"What's the matter?" asked Craig.
"It's about my mother," he blurted out. "She seems to be getting worseall the time. Miss Sears is alarmed, and Betty is almost ill herselfwith worry. Dr. Wilson doesn't seem to know what it is that affectsher, and neither does the new nurse. Can you DO something?"
There was a tone of appeal in his voice that was not like theself-sufficient Reginald of the day before.
"Does there seem to be any immediate danger?" asked Kennedy.
"Perhaps not--I can't say," he urged. "But she is gradually gettingworse instead of better."
Kennedy thought a moment. "Has anything else happened?" he asked slowly.
"N-no. That's enough, isn't it?"
"Indeed it is," replied Craig, trying to be reassuring. Then,recollecting Betty, he added, "Reginald, go back and tell your sisterfor me that she must positively make the greatest effort of her life tocontrol herself. Tell her that her mother needs her--needs her well andbrave. I shall be up at the house immediately. Do the best you can. Idepend on you."
Kennedy's words seemed to have a bracing effect on Reginald and a fewmoments later he left, much calmer.
"I hope I have given him something to do which will keep him frommussing things up again," remarked Kennedy, mindful of Reginald'sformer excursion into detective work.
Meanwhile Craig plunged furiously into his study of the substances hehad isolated from the saline solution in which he had "washed" theblood of the little Pekinese.
"There's no use doing anything in the dark," he explained. "Until weknow what it is we are fighting we can't very well fight."
For the moment I was overwhelmed by the impending tragedy that seemedto be hanging over Mrs. Blake. The more I thought of it, the moreinexplicable became the discovery of the mold.
"That is all very well about the mold on the gelatine strip in theletter," I insisted at length. "But, Craig, there must be somethingwrong somewhere. Mere molds could not have made Buster so ill, and nowthe infection, or whatever it is, has spread to Mrs. Blake herself.What have you found out by studying Buster?"
He looked up from his close scrutiny of the material in one of the testtubes which contained something he had recovered from the salinesolution of the diffusion apparatus.
I could read on his face that whatever it was, it was serious. "What isit?" I repeated almost breathlessly.
"I suppose I might coin a word to describe it," he answered slowly,measuring his phrases. "Perhaps it might be calledhyper-amino-acidemia."
I puckered my eyes at the mouth-filling term Kennedy smiled. "It wouldmean," he explained, "a great quantity of the amino-acids,non-coagulable, nitrogenous compounds in the blood. You know theindols, the phenols, and the amins are produced both by putrefactivebacteria and by the process of metabolism, the burning up of thetissues in the process of utilizing the energy that means life. Butunder normal circumstances, the amins are not present in the blood inany such quantities as I have discovered by this new method ofdiffusion."
He paused a moment, as if in deference to my inability to follow him onsuch an abstruse topic, then resumed, "As far as I am able todetermine, this poison or toxin is an amin similar to that secreted bycertain cephalopods found in the neighborhood of Naples. It is anaromatic amin. Smell it."
I bent over and inhaled the peculiar odor.
"Those creatures," he continued, "catch their prey by this highlyactive poison secreted by the so-called salivary glands. Even a littlebit will kill a crab easily."
I was following him now with intense interest, thinking of theastuteness of a mind capable of thinking of such a poison.
"Indeed, it is surprising," he resumed thoughtfully, "how many aninnocent substance can be changed by bacteria into a virulent poison.In fact our poisons and our drugs are in many instances the closerelations of harmless compounds that represent the intermediate stepsin the daily process of metabolism."
"Then," I put in, "the toxin was produced by germs, after all?"
"I did not say that," he corrected. "It might have been. But I find nogerms in the blood of Buster. Nor did Dr. Wilson find any in the bloodsmears which she took from Mrs. Blake."
He seemed to have thrown the whole thing back again into the limbo ofthe unexplainable, and I felt nonplussed.
"The writer of that letter," he went on, waving the piece of sterileplatinum wire with which he had been transferring drops of liquid inhis search for germs, "was a much more skillful bacteriologist than Ithought, evidently. No, the trouble does not seem to be from germsbreathed in, or from germs at all--it is from some kind of germ-freetoxin that has been injected or otherwise introduced."
Vaguely now I began to appreciate the terrible significance of what hehad discovered.
"But the letter?" I persisted mechanically.
"The writer of that was quite as shrewd a psychologist asbacteriologist," pursued Craig impressively. "He calculated the moraleffect of the letter, then of Buster's illness, and finally of reachingMrs. Blake herself."
"You think Dr. Rae Wilson knows nothing of it yet?" I queried.
Kennedy appeared to consider his answer carefully. Then he said slowly:"Almost any doctor with a microscope and the faintest trace of ascientific education could recognize disease germs either naturally orfeloniously implanted. But when it comes to the detection ofconcentrated, filtered, germ-free toxins, almost any scientist might bebaffled. Walter," he concluded, "this is not mere blackmail, althoughperhaps the visit of that woman to the Prince Henry--a desperate thingin itself, although she did get away by her quick thinking--perhapsthat shows that these people are ready to stop at nothing. No, it goesdeeper than blackmail."
I stood aghast at the discovery of this new method of scientificmurder. The astute criminal, whoever he might be, had planned to leavenot even the slender clue that might be afforded by disease germs. Hewas operating, not with disease itself, but with something showing theultimate effects, perhaps, of disease with none of the preliminarysymptoms, baffling even to the best of physicians.
I scarcely knew what to say. Before I realized it, however, Craig wasat last ready for the promised visit to Mrs. Blake. We went together,carrying Buster, in his basket, not recovered, to be sure, but a verydifferent little animal from the dying creature that had been sent tous at the laboratory.