by Various
"The forms of oxygen? Why, there is only one, oxygen gas. Wait a minute though, there is another form, ozone. Are there any more?"
"None that have been previously listed and studied, but at least one other form exists. Those crystals are pure oxygen."
"Impossible! Oxygen is a gas at all ordinary temperatures."
* * * * *
"Yes, a gas, but one whose density varies. Oxygen, to which we chemists assign the formula O{2}, meaning that its molecule consists of two atoms of oxygen, has a weight of 32 grams per gram molecule. Ozone, to which we assign the formula O{3}, meaning that its molecule contains three atoms of oxygen, weighs fifty per cent more or 48 grams per gram molecule. This new form has a density less than water, but tremendously greater than any known gas. I have not yet been able to determine its structure, so I will have to assign to it the formula, O_{x}, meaning an indefinite number of atoms per molecule. The only name which suggests itself is oxyzone, a combination of oxygen and ozone.
"The stuff is a polymerization, or condensation, to speak roughly, of the oxygen of the air. The oxygen takes this form which the lungs cannot assimilate except with great difficulty and with great damage to the tissues. The oxyzone will break down rapidly under the influence of sunlight or of any ray whose wave-length is shorter than indigo. As a result, it disappears as soon as the sun is up and it will reappear after dark. That is why I suggested X-rays as a treatment. They have a very short wave-length and will penetrate tissues and affect the particles in the lungs themselves. Once the material is removed from the lungs, the cauterization of the tissue ceases and it is merely a matter of slow recovery."
"It is a marvelous discovery, Doctor. I can foresee great uses for it in medical science if a way can be found to produce it."
"Just now we are much more interested in stopping its production than in producing it. Carry on with the line of treatment I have prescribed and be ready for a busy time to-night."
* * * * *
From the hospital, Dr. Bird made his way to the headquarters building where he conferred with Colonel Wesley on the measures being taken to clear the proving ground of all persons not strictly necessary for its guarding. The commanding officer, when he learned Dr. Bird's plans, wished to send guards with him, but the doctor promptly vetoed the scheme.
"My assistant, Mr. Davis, won't be able to fix up more than two masks before dark, Colonel," he said, "and you would just be condemning men to death to send them with me into that fog without proper protection. I can see that you are anxious to know what is causing it, but I'm not ready to tell just yet. I had given your medical officer enough information to enable him to treat the hospital cases scientifically, and to-morrow or the next day I hope to be able to tell you all about it. Now, if you'll pardon me, I'm going to the laboratory to see how Mr. Davis is getting along. It will be dark in three-quarters of an hour and I hope that everyone will stay under cover as much as possible."
Davis looked up as Dr. Bird entered the laboratory.
"I'll have the masks completed in an hour, Doctor," he said, "but I don't know how much value they will be. If the oxygen polymerizes before it enters the body, these masks ought to stop it, but if it polymerizes under the influence of heat and moisture in the lungs, they will be useless."
"I'll have to take a chance on that, Davis. From the description of the fog, I strongly suspect that the process takes place outside the body. Have you had your supper?"
"No, Doctor."
"Neither have I. I'll go over to the officers' mess and get a bite to eat. As soon as you have those masks done, get your supper and then telephone me at the club. If Carnes isn't back, I may have to ask you to drive me down toward Michaelville."
"I'll be very glad to, Doctor."
* * * * *
Carnes had not returned when Davis called Dr. Bird at the officers' club two hours later. Night had fallen and everyone on the proving ground sat behind tightly closed windows with lights blazing on them, wondering whether the finger of death would reach in from the swamp to touch them. The fog had not yet made an appearance on the main post and Dr. Bird had no fear of it when he entered his car and drove down to pick up his assistant.
Davis came out to meet him with a curious hood made of vitiolene and rubber, pulled down well over his head. In his hand he carried a second one. Dr. Bird adjusted the second mask and the two men loaded the rear of the car with apparatus designed for collecting samples of air. The outside of each sample cylinder was heavily coated with black rubberine paint. At a word from the Doctor, Davis took the wheel and drove off along the winding ribbon of concrete which led to the upper end of the Michaelville range.
For a mile they drove through a clear, calm night with no traces of fog apparent. Dr. Bird's eyes continually searched the swamps on both sides of the road.
"Stop!" he said suddenly, his voice coming muffled through the enveloping mask. The car stopped and the Doctor pointed to the west. Over the swamp a few stray fingers of fog were curling up from the water.
* * * * *
Leaving Davis in charge of the car, Dr. Bird donned rubber hip boots and with a gas cylinder in his hand, splashed through the water toward the fog. He reached the place with no difficulty and spent ten minutes trying to collect a sample. Finally, with a muttered exclamation, he removed his mask and inhaled deeply a dozen times. Carrying the mask in his hand, he made his way back to the car.
"False alarm," he said as he pulled on his mask. "It was so thin that I couldn't get a sample so I tested it by breathing. There isn't a trace of cough in that fog. Drive on."
A half mile farther along the road, a curtain of fog swept in on them, momentarily hiding the road from view. They were through the belt of fog in a few feet and the car came to a stop. Dr. Bird sprang out, gas cylinder in hand. He returned to the car shortly.
"We may have what we are looking for, Davis," he said, "but I am not at all certain. It looked very much like ordinary fog. Let's go down to the range."
The car drew up between the two main buildings of the Michaelville front. The air was clear as far as they could see, but from under the north building, a tiny wisp of fog was coming. As it came under the glare of the three huge arc-lights which flooded the ground with light, it grew more tenuous and gradually dissipated into nothingness. With an exclamation of satisfaction, Dr. Bird bent down and thrust the end of a cylinder under the building. He removed it in a moment as the fog began to stream from the upper end. Carefully he closed the pet-cocks of the tube and replaced it in the car. He filled a half dozen tubes before he was satisfied.
"I'd like to go down to the water," he said through his mask. "What kind of a jigger do they run on that track?"
"It's a Ford scooter, I was told. It's probably in that shed."
* * * * *
Half an hour later the two men were running the scooter down the four miles of narrow gage track which separated Michaelville from the Bush River. A few scattered patches of fog could be seen on either side of the track, but none were of sufficient thickness to warrant much success in sample taking. At the water front Dr. Bird looked across the half mile wide river and grunted.
"The tide won't be in for another three hours," he said. "Right now there isn't over sixteen inches of water in there."
Carnes was waiting in the well lighted laboratory when they drove up.
"All right, Davis," said the doctor, "get busy on those samples. If you can't make out the first two, don't crack the others but leave them for me. Give Carnes your mask; he'll drive the rest of the night.
"What luck, Carnesy?" he asked, as the detective, wearing Davis' mask, drove toward the officers' club.
"No stray plane landed or even flew over here last night so far as I could learn. Most of the boats on the bay were either known or lent themselves to ready identification. There were four that I couldn't exactly place, but I think we can safely discard all but one. Some fishermen were pulling nets on the bay about half a mile outside the mouth of th
e Bush River last night. About eleven, a boat running without lights passed them. They said that they could not hear an engine running, but just a dull hum and the gurgle of a propeller. They hailed it, but got no answer. It faded away into the darkness and they think it was headed toward the mouth of the Bush River. They had their nets up and reset in another hour but the boat didn't reappear."
"Hmm. High tide was at ten minutes after midnight. There was plenty of water in the river at that hour. It sounds promising."
"I thought of telephoning Washington and getting a Coast Guard cutter put on patrol in the bay but I didn't like to do it without your sanction."
"It might have been a good idea, but on the whole it's probably better that you didn't. Carnes, we'll go down to the water front and see whether anything shows up to-night. High tide will be about eleven-thirty. It's about half-past nine now. We'd better get going."
* * * * *
On the second drive to Michaelville, the fog patches were quite noticeably denser than they had been earlier in the evening. Three times the car had to pass through bands of fog which covered the road. As they passed the second one Carnes suddenly began to cough.
"What's the matter, old man?" cried Dr. Bird, a note of anxiety in his voice. For a few moments Carnes could not answer for coughing. He seized the mask to tear it from his head but Dr. Bird restrained him. In a few minutes his voice became intelligible.
"It seemed like that fog bit right into my lungs, Doctor," he gasped. "I felt as if I were choking. It's better now."
"Are you sure your mask isn't leaking, Carnes? It'll be all up with you if it does. Test it."
The detective closed the intake valve of the mask and expelling all of the air from his lungs, took a deep breath. The air whistled noisily in through the outlet valve.
"The devil!" cried the doctor. "Take that mask off and let me look at it."
A few moments were enough to make the needed repairs and they drove on. Carnes still coughed from time to time. At Michaelville, they started the scooter and ran down the track to the river. They secreted the scooter under the parapet on the water pent-house and walked to the river's edge.
"There's no telling just where they may land, Carnes," said the doctor reflectively, "but this looks like the most likely place. I'll tell you what we'll do. The river narrows a good deal about half a mile east of here. You go up to the narrows and keep watch while I stay here. If any craft passes you, follow it upstream until you find me. If they land, handle the situation as well as you can alone. If you hear any shooting, come as fast as you can leg it. I'll do the same."
* * * * *
The detective stole away into the darkness and Dr. Bird settled himself for a long vigil. For an hour nothing broke the stillness of the night. Suddenly the doctor was on his feet, peering downstream. A faint purring murmur came over the water, so faint that no one with less sensitive ears than the doctor's could have detected it. Assured after a few minutes of listening that some kind of a craft was coming up the river, the doctor sank back into his hiding place, an automatic pistol firmly grasped in his long tapering fingers.
The purr came nearer, but it was not appreciably louder. The gurgle of water past the prow of the boat could be heard and Dr. Bird could see a long ribbon of white on the water where the craft was passing. He stepped from his cover and leaned forward, straining his eyes to see the boat. It passed beyond him and continued up the river. He stepped quickly along the river bank, trying to keep it in sight. Suddenly he paused. The boat had turned and was coming back. Hurriedly he returned to his hiding place.
The boat came down the river until it was opposite the point where he crouched, and then it turned and came in toward the shore. Dr. Bird gripped his pistol and waited. When the craft was less than twenty feet from shore it stopped and a guttural voice spoke. Dr. Bird started. He had expected the language to be Russian, but it came as a shock to him, nevertheless. He strained his ears and cursed his inability to make out the words. Dr. Bird had been assiduously studying Russian under the tutelage of his new secretary for some months, but he had not yet progressed to the stage where he could readily understand it. The gift of languages was one which the erudite doctor did not possess.
* * * * *
The boat lay motionless for several minutes. Nervously the doctor glanced at his wrist watch. He barely stifled a cry of amazement. From the face of the luminous dial, long streamers of faintly phosphorescent light were streaming. He whirled to meet an attack from the rear but he was too late. Even as he turned the muzzle of a pistol pressed into his back and a voice spoke behind him.
"Drop that pistol, Doctor, or I'll be under the unpleasant necessity of making a hole in you."
Reluctantly, Dr. Bird dropped his pistol and the voice went on.
"Really, I hardly expected to catch you by surprise, Doctor. I thought you were clever enough to realize that our boat would be equipped with an ultra-violet searchlight. However, even the best minds must rest sometimes, and yours is due for a nice long rest. In fact, I might almost prophesy that it will be a permanent rest."
Dr. Bird shivered despite himself at the cold mercilessness of the railing voice behind him. The accents were ones which he did not recognize. His captor chuckled for a few moments and then called out in Russian. The boat came into the shore and eight figures climbed out. Two of them bore a small chest which they set down on the wharf. One of the figures picked up the doctor's automatic and his captor stepped in front. A flashlight gleamed for an instant and Dr. Bird started in surprise. The men wore no masks but only a plate of glass which protected their cheeks and eyes. Fastened to the neck of each one, below the chin, was a long tube which gleamed like glass. They wore heavy knapsacks strapped to their backs from which wires ran to each end of the bars.
"Those protectors make your enveloping head-mask look rather clumsy, don't they, Doctor?" said his captor mockingly. "It's too bad you didn't think of them first. It must be such a blow to your pride to think that anyone had invented something better than yours. Really, that mask of yours worries me. Remove it!"
* * * * *
At his words two of the men stepped forward and tore the doctor's mask roughly from his head. The mocking voice went on.
"In view of the fact that you have only a few hours of life left, Dr. Bird, it will give me pleasure to let you know how thoroughly you have been defeated. You may not know me by sight, although my name may not be unfamiliar. I am Peter Denberg."
He turned the flashlight for an instant on his own face, and Dr. Bird gazed at him keenly.
"I'll know you the next time I see you," he muttered, half to himself.
"The next time you see me will be in the hereafter, if there be such a thing," laughed the Russian. "The sweetest blow of all is now about to fall. We expected you to be here and came prepared to capture you. Had we not known that the arch enemy of the people would be here to-night, we would have struck at a point miles away. Do you know who betrayed you? It was one we placed in your laboratory for the very purpose which she served."
He turned on the light again and it picked out of the darkness another face, a long oval face with startlingly red lips and dark oval eyes which glowed as with an internal flame. As the face became visible, the red lips drew back, exposing strong white teeth and the words were literally spat out.
"Swine!" she hissed. "Bourgeois! Did you think you could bribe me with your gifts to tolerate your vileness? I have brought about your downfall and death, Dr. Bird. I, Feodrovna Androvitch! Now will I avenge my brother's death at your hands!"
She sprang forward and spat full in the doctor's face. Dr. Bird fell back for an instant under the ferocity of her attack and long nails ripped the skin from his face. Denberg stepped forward and caught her wrists.
"Gently, sister," he warned. Feodrovna struggled for an instant but gave way to the powerful muscles of the communist leader. "There is no need for anything of that sort," he went on. "In a few moments we will open the chest which
we have and then you will enjoy the amazing spectacle of the man who has temporarily checked the plans of our leader a dozen times, gasping for breath like a fish out of water. Start your protectors."
* * * * *
Each of the Russians closed a switch on the knapsack which he wore. From the bars below their chins came a dull violet glow which made their faces stand out eerily in the darkness. The flashlight was centered on the box which Dr. Bird could see was made of lead, soldered into a solid mass. At a word from Denberg, one of the Russians stepped forward with a long knife in his hand and started to cut open the box.
With a sudden effort, Dr. Bird shook himself loose from the two men who were holding him and sprang forward. Denberg turned to meet him and the doctor's fist shot out like a piston rod. Full on the Russian's chin it landed and he went down like a poled ox. Two of the Russians closed with him but the two were no match for Dr. Bird's enormous strength, fighting as he was for his life. He hurled one away and swung with all of his strength at the other. His blow struck glancingly, and while the Russian spun away under the blow, he did not fall. A man caught at him from the rear and Dr. Bird whirled, but as he did so, two men seized his arms from behind. Mightily the doctor strove but others flung themselves on him. He straightened up with a superhuman effort and then from an unexpected source came help.
One of the men holding him gave a choking gasp and reeled sideways. Dr. Bird felt his neck deluged with liquid and the smell of hot blood rose sickeningly on the air. He shook himself loose again and smote with all of his strength at his nearest opponent. His blow landed fair but at the same instant an iron bar fell across his arm and it dropped limp and helpless. Again a knife flashed in the darkness and a howl of pain came from the Russian who felt it bite home.
"We are attacked!" cried one of them. They whirled about, their flashlights cutting paths through the thickening fog. With her back to the crippled doctor's Feodrovna Androvitch held aloft a bloody knife.