Crime Under Cover

THE throng from the train gate poured into the vast concourse of the Washington Union Station and melted away, much to the amazement of Jerry Croft, and to his annoyance, too. He had counted upon staying with the crowd, thereby keeping himself unnoticed; but it simply couldn't be done.

This was his first visit to Washington, and he had heard, but forgotten, that the concourse at the Union Station was large enough to contain an army of fifty thousand men. At this moment, Jerry felt that he needed about forty-nine thousand others in order to lose himself as he had planned.

His walk across to the main waiting room seemed like a one-man parade, and he felt that all eyes were upon him, until he realized that many of the other people were too far away to identify him, even if they knew him.

In a way, he was lost, after all, but it didn't occur to him, until later, that persons who might have spotted him at the train gate would look as though they were lost while they trailed him.

The waiting room was large, too, but it was fairly crowded, which was something of a help. Jerry found his way to the taxicabs, and hailed one just as someone else took it. He turned around and saw the dark-faced man with the bulgy forehead step back from sight.

He was an odd-looking chap, as Jerry had noted on the train. Odd, that he had arrived at the cab rank as soon as Jerry; odder, that he had gone back into the waiting room.

Maybe he had forgotten something; perhaps he wanted to send a telegram. People did send telegrams from Washington, as Jerry could easily prove, because he had one in his pocket.

It was the telegram that had come from Professor Urlich Ardlan, and it was the thing that had brought Jerry Croft to Washington. Jerry didn't have to look at the telegram to remember it; he knew its brief message by heart.

A cab pulled up and Jerry tossed his small but heavy suitcase into it, as he took another look for the man with the big, dark brow. Not seeing the fellow, he decided that it was safe to confide in the cab driver, so he told him to drive to the World Wide Cafe, the meeting place the professor had named in the telegram.

Why Professor Ardlan, whose chief diet was milk toast, should have picked a restaurant as a rendezvous, was something rather baffling; but then, Ardlan's ways were always curious, and Jerry had learned to expect almost anything from him.

Some people insisted that Ardlan was crazy, and Jerry had learned not to dispute them, rather than have himself considered a bit touched, too. In fact, through association with the professor, Jerry wondered at times whether he was still wholly sane, particularly when he found himself worrying about men with big foreheads and thinking they were on his trail.

The cab worked its way to Pennsylvania Avenue, and sight of that broad boulevard, glittering with light, intrigued Jerry. He was riding away from the capitol building, but in what direction he hadn't an idea, and when the cab turned off into a side street and swung along another, its passenger was totally confused. The cab stopped in front of a prosperous-looking restaurant that bore the sign:

WORLD WIDE CAFE

This, at least, was Jerry's destination. He alighted from the cab, paid the zone fare and entered the restaurant, carrying his suitcase. A hat-check girl wanted to take it, but Jerry shook his head and she smiled.

The girl had seen others like Jerry before. He was reasonably handsome, and very earnest, as if he had important business to handle, with the answer to it in the bag that he carried. He was looking for someone, as such arrivals in Washington usually did.

Jerry wouldn't have had trouble finding Ardlan, had the professor been in the restaurant. Professor Ardlan had much the appearance of a shaggy-maned lion, except that his hair was gray, and, in true leonine fashion, he bellowed at everyone who approached him, which usually meant the waiters when he dined in public.

There was no one in the cafe like Ardlan. Jerry was sure, because he knew that he would have heard the professor, even if he couldn't see him.

So Jerry took a table near a corner from which he could watch the door. He put the suitcase on another chair, where it was within easy reach. Containing, as it did, a collection of chemical formulas, mostly pertaining to gases, the bag was of importance to Jerry, especially as the formulas represented his own research of more than six months.

PEOPLE were coming into the restaurant, but Ardlan was not among them. Jerry wondered if he really had remembered the telegram correctly. He pulled it from his pocket, and found that he was right. It said to come to Washington on the express that arrived at six thirty-five, and to meet Ardlan at the World Wide Cafe.

So Jerry put the telegram away and studied the menu, deciding to get a head start on his dinner before the professor showed up for milk toast.

Men were seating themselves at the next table, and Jerry could overhear their conversation. It wasn't in English, but Jerry had traveled around enough to know smatterings of other languages to the point of identifying them.

This happened to be one that he couldn't class, though it had snatches of familiarity. (Note: Unknown to Jerry Croft at this time, the language being spoken in the cafe is Esperanto. Jerry will learn the meaning of this restaurant conversation later in the story. Throughout the story; if the text itself does not make the meaning of the Esperanto clear, when it is spoken, a footnote will give the translation to the reader. For further information about Esperanto, please turn to the end of this story.) At least, the men spoke plainly, so that their pronunciation was recognizable.

"Mi sekvis lin el la stacio," said one. "Li estas la viro."

"Bonega," spoke another. "Ni observos lin."

Jerry looked toward the speakers and stared. One of the four was the man who had been on the train, there was no mistake about it. Viewing the fellow in profile, Jerry saw the big forehead and its bulge; as for the man's complexion, it was definitely dark, though the cafe was well lighted.

The others were speaking, and Jerry couldn't catch the odd words in the babble. Fortunately, at that moment a waiter approached their table. They silenced, without noticing Jerry, but even the sudden quiet was curious. They weren't worried about the waiter hearing them; they wanted to hear what he had to say, and it was in their own language!

"Oni audos vin," the waiter confided. "Se iu komprenas, gi estus malbona.

There were nods from the rest. With wary looks, they began to point out items on the menu, that the waiter jotted down while he nodded. By then, Jerry was behaving warily, too, but from the corner of his eye he was checking on the bulge-headed man's comrades.

They looked foreign, but of what nationalities, Jerry could not guess, except that they varied. The waiter, obviously a member of their group, looked more American than the rest, but his inset face, tawny in shade, marked him as a probable unknown quantity.

Sliding his hand in his coat pocket, Jerry found a little notebook and rested it on his knee. He had a stubby pencil handy, too, and he decided to jot down what he heard next, particularly if the bulge-browed man spoke it.

The fellow was the one who did speak, just after the waiter had finished taking the orders. He motioned to the waiter and said slowly, importantly:

"Alportu al mi ion florbrasiketo."

The waiter nodded, and repeated:

"Florbrasiketo. Mi memoros."

Pocketing the order list, he became a typical waiter as he strolled away, and Jerry, writing the words as well as he could remember them, was definitely sure of one: florbrasiketo. He regarded it as the most important thing that he had caught from the conversation.

Apparently, by mutual consent, the four men were saying little; when they did, they spoke more rapidly and kept their voices lowered; so that neither Jerry, nor any others close by, could overhear them, but their tones indicated that they were still using the peculiar language that they preferred.

A different waiter took Jerry's order, and while he ate, Jerry kept watching for the professor and speculating about the tribe at the neighboring table. It might be just a coincidence that the bulgy-browed man had come to the World Wide Cafe, and not a remarkable one at that, since the name of the place indicated that it was cosmopolitan.

Nevertheless, Jerry didn't like it, particularly when Professor Ardlan did not appear.

ARDLAN was somewhere in Washington; he had come to the capital to sell the government a wonderful idea that he considered to be of military value, and the fact that Ardlan was staying in Washington indicated that he was getting somewhere with it.

He had left Jerry with enough work to keep him busy indefinitely, instructing him to stay at it until further word arrived. The further word had been the telegram.

Jerry had enough money with him to stay at a hotel, but that wouldn't help to find Ardlan. The professor was absent-minded at times, but there were others with him, and one in particular, Trennick, wouldn't let him forget an important appointment. In fact, Trennick had probably sent the telegram for the professor, unless -

The thing rang home while Jerry was looking at the man with the bulgy forehead. Could it be that the telegram itself was a hoax? That someone in the queer-looking outfit had sent it, signing the professor's name, and that the man with the big brow had been assigned to pick up Jerry's trail along the way?

Professor Ardlan often had ideas that people were following him, but could never furnish proof. In Jerry's case, it was different. He couldn't say that the man had followed him to the cafe, but the fellow had come to the same place, which amounted to the same thing, and perhaps more. It might even mean that he had known where Jerry intended to go.

There was a way to find out. Jerry's waiter had left the check, and it came to an even sum, allowing for the tip. His hat and suitcase close at hand, Jerry reached for them under cover of the table.

He noted that the man with the bulgy head was busy over a plate of broccoli and figured it a time for opportune departure. Before any of them realized it, Jerry had his hat and bag and was on his way.

There was a cab outside, and stepping right into it, Jerry looked back. He saw the waiter - the one who talked the odd language - gesticulating to the men at the table, and they were coming to their feet, not bothering about their checks, which the waiter, as one of their crowd, could pay for them.

Men didn't bolt from the middle of a meal unless there was a fire, or they had chosen to go after someone who had left too soon.

In this case, the early bird was Jerry. He didn't intend to waste his advantage hunting for worms. He was in the cab, his suitcase with him, when he heard the driver say:

"Where to?"

"Next corner," responded Jerry. "Turn left, then I'll give you the address. I'm in a hurry."

Hurry or no hurry, the cab was just turning the corner when Jerry saw the quartet tear from the World Wide Cafe and pile into a speedy-looking sedan that had pulled up to receive them. Then Jerry's cab was around the corner and the driver was asking:

"Where next?"

"Straight ahead," snapped Jerry, "and go like blazes!"

"But this takes us into the Potomac -"

"Then turn off wherever you can, but keep going. Look into the mirror; you'll see that somebody is after us."

The driver looked into the mirror and caught a glimpse of Jerry, as well as the car behind. Jerry struck him as all right, whereas the pursuing car didn't. The cabby needed no further urge.

He took the straightaway at his fastest clip, swerved finally into a drive that followed the river's curve. The other car did the same, and when Jerry looked back, he not only saw that it had gained, but had the sinking impression that still another pursuing car was coming along with it.

Grimly, Jerry Croft set himself to meet the unknown future, confident that when the critical moment arrived, all would not be quiet along the Potomac!

THE cab took a sudden swerve, ripped its way between two Japanese cherry trees, hooked another, skewed about, and wound up within a biscuit's toss of the river bank. Two doors shot open at once - one on the left front, the other at the right rear. The front door emitted the cabby, the rear one disgorged Jerry and his bag.

Staying on the road and stopping farther on, the pursuing sedan let loose its four-man quota. They saw Jerry and came after him, spreading out as they wrenched past the cherry branches.

Jerry tried to chuck the suitcase into the Potomac River, but it was heavier than a biscuit and wouldn't carry that far. He went after it, trying to kick it ahead of him. Failing he ducked around the front of the cab, hoping that he could scout up the cabby and enlist his aid in going after the four men, if they obtained the suitcase.

They didn't bother about the bag. They wanted to get Jerry, instead. Two rounded the front of the cab, as he had; the other pair cut in from the rear. Jerry saw the second car of the pursuit line, as it nosed in through the cherry-tree wreckage that the cab had caused. He'd only be cut off if he kept in that direction. Desperately, Jerry turned, and made his predicament immediate.

Four men were upon him, a pair from each direction, and they were swinging things that gleamed: guns. His hands up to ward off the blows, Jerry felt a surge of overwhelming blackness that struck like an avalanche. He went down beneath it, sensing blows that he thought must come from slugging guns, only to realize that feet were kicking him.

Feet that went jouncing away in one direction, toward the river, as if one pair of attackers had driven back the others.

Staring from propped-up elbows, with his hands clapped to his head, Jerry thought that the four were fighting among themselves - which seemed incredible for the moment, but faded into simplicity at what he realized next.

They weren't fighting each other; they were battling blackness! Slugging wildly, guns were meeting others that Jerry could not see, but could hear by their clicks.

It was a shadowy struggle with an invisible foe, so far as Jerry could view it, until the swirl of battle carried the melee into the glare of the cab's headlights.

There, with invisibility denied him, the fighter who had taken on the odds declared himself, with a laugh that carried weirdly out across the river. It was a laugh of challenge, defiant in its mockery, threatening ill to the opposition, regardless of their number. Amid the swirl, Jerry saw the figure of the lone, intrepid fighter.

He was The Shadow!

Cloaked in black, a slouch hat upon his head, this terror to men of evil was sledging with a pair of automatics that were as large as bludgeons. His gloved fists were using their weapons with such advantage, that he was bashing down opposing guns and beating away warding hands.

Jerry had never seen The Shadow; in fact, did not identify him at the moment. He saw a being in black, a superhuman warrior, which was enough. He knew that The Shadow must have come from the second car; that he had been upon the trail of the pursuers themselves.

Those men who babbled in a strange tongue were not profiting by The Shadow's arrival, and recognizing it, they dropped their silent struggle.

Scattering like debris tossed by a tornado, they came about to blaze with their guns; they were in darkness, and they were shooting back at the light that fronted the cab, hoping that wild aim would clip their foe.

But The Shadow was no longer a target; he, too, had gone into darkness. Only Jerry glimpsed the long plunge that he thought, at first, had carried The Shadow over the river's brink.

FROM the water's edge, guns spoke. Their stabs told that The Shadow was not submerged; he was using the low entrenchments afforded by the bank to knife back his replies to futile shots.

Yelps from near the taxicab indicated that The Shadow was scoring hits. Jerry heard one man stagger past him, while the others ran. Rising, he tried to grab at least one fugitive, but all were past him, heading toward the road.

Again, The Shadow's laugh; this time, its trailing tone carried a warning that Jerry didn't understand at first. Another man was joining Jerry - the cabby, who had regained his nerve, now that he was with the hounds instead of the hares.

Somewhere behind them was The Shadow; confident of his support, Jerry thought that this pursuit was what The Shadow wanted.

He found out differently when he and the cabby overtook the four men. Two were helping the staggering fellow, while the third, who happened to be the bulge-headed man, was carrying one arm rather limp, as though from a deep flesh wound. It was he who turned to brandish a revolver at Jerry and the cabby - at sight of which, they dived apart.

Instantly, The Shadow's gun spoke anew from somewhere in the background. Then did Jerry understand the folly of his own pursuit; the reason for The Shadow's warning. Not only Jerry, but the cabby, too, had blocked off The Shadow's fire. Otherwise, the cloaked marksman would have halted the four fugitives, to the final man, by means of his long-range fire. By now, it was too late.

Two of the men, unscathed, had put their stumbling companion into the car; the driver was starting it away when Jerry saw the fourth fugitive, the man with the big forehead, spring into the front seat.

The Shadow tongued a few shots after them, and they jabbed back, but his purpose was merely to draw their fire away from Jerry and the cabby, who were much closer to danger than The Shadow - if he could be regarded as in danger at all.

Intervening trees helped render futile the last exchange of shots, but Jerry was alarmed by the sudden way The Shadow's gunfire halted - until he heard sirens wail and saw motorcycles whirl in from a broad, curving driveway.

Police had heard the gunfire, and by allowing the escaping opposition the privilege of the last few wasted shots, The Shadow had dispatched the law along their trail.

The cabby was hurrying back to the cab, and Jerry decided to do the same, on the chance of meeting the mysterious fighter who had so ably rescued him. Finding The Shadow in the dark would be impossible, but Jerry hoped that his new friend might declare himself.

On the way to the cab, however, Jerry remembered the suitcase. He knew that the men who talked the strange tongue hadn't taken it, so it logically belonged at the place where Jerry had last kicked it.

Finding the place was the trouble. The cabby had turned off the headlights, in order not to attract any police who might come trailing after the first squad, so Jerry decided to ask him to put them on again. He reached the cab in the darkness; the driver heard him, and said:

"Hop in."

"The suitcase," began Jerry. "I had it with me -"

"It's here in the cab."

The suitcase was in the cab, and Jerry eagerly opened it, while the cab was backing around and nosing for the opening between the trees. The lights were on again, and Jerry saw that The Shadow's car was gone.

As swiftly as he had arrived, the mysterious fighter had departed, hoping, perhaps, that he could pick up the racing motorcycles, to find the fugitive car that was trying to outrun the police.

Jerry's formulas were just as he had packed them. The driver was taking to the curved drive, and Jerry saw that it skirted a roundish landlocked reservoir - the Tidal Basin, jutting in from the Potomac.

"Guess they kind of had us worried," piped the cabby, from the front seat. "You're a cool guy, though. I could tell that when you handed me the bag and told me to put it here in the cab."

"When I told you -"

"Yeah. Or, maybe" - the cabby paused, to peek at Jerry in the mirror - "or maybe you were still kind of groggy."

"I guess I was," acknowledged Jerry. "I don't exactly remember giving you the suitcase."

"I guessed maybe you didn't."

THE cab was swinging into a meshwork of streets where laid-out squares, simple in themselves, were rendered mazelike by the angular crossings of intervening avenues. The cabby knew his way around, for he performed twists that kept carrying the cab along one general direction, but why he was heading that way, Jerry couldn't understand.

Jerry was about to put a question, when a sudden idea struck him. Instead of asking the cabby where they were going, he expressed the query in another way.

"You know where you're going, don't you?"

"To the address you gave me," returned the cabby. "That is, if you remember telling it to me, the same time you passed me the suitcase."

"I remember that part," assured Jerry. "I just wanted to make sure you got it straight."

For all that Jerry knew, their destination might be in Timbuktu, not Washington, but at least he understood the answer to the riddle, as well as the puzzle of the suitcase.

It must have been the cloaked rescuer who had handed the cabby the bag and given him the address in a tone which could have been Jerry's. Up to that time, any tone could have been Jerry's, so far as the cabby was concerned, for their only previous conversation had been an excited one outside the World Wide Cafe.

Maybe the cabby was catching the discrepancy, now that Jerry was talking normally. Maybe not, but in either case it didn't matter. They were bound somewhere, at The Shadow's order, and Jerry Croft was willing to trust the mysterious friend whose fade-out had been as remarkable as his battle.

The cab swung into one of Washington's many secluded streets, where old houses stood half hidden behind rows of shade trees. The cabby poked along looking for the number that he wanted. Finally halting in front of the oddest house of all, he asked:

"Is this the place?"

"It looks like it," Jerry vouchsafed. "I guess you heard me right."

He paid off the cab driver; went to the door of the forbidding house, wondering suddenly whether he might be walking into another trap. The cab was lingering, as if through its driver's curiosity, and Jerry was remembering that he had only the cabby's say-so regarding the address given by the man he thought was his passenger.

Maybe the fellow was in the game and had taken Jerry to the river side so the pursuers could box him. With The Shadow gone, the cabby could have faked his yarn, and this very house might be the headquarters of the strange-speaking men who fled The Shadow's wrath!

If so, the cabby would give the alarm if Jerry welshed at entering the house. If not, he'd at least wonder. The door latch was clicking, and Jerry faced the barrier with tightened fist, hoping that he'd meet The Shadow, or someone who served him, rather than the bulge-headed man, or a similar enemy.

He met neither. Half stepping across the threshold, Jerry continued on a pace, staring in real surprise. His hand came up, its fist unclenched, to receive the clasp of a shaggy-haired man who greeted him with a pleased and booming laugh.

Jerry Croft had kept his appointment in Washington - or, rather, The Shadow had arranged that he should keep it. The man who was greeting Jerry was none other than his singular employer, Professor Urlich Ardlan!

INSTEAD of clearing the mystery, the meeting with Ardlan only deepened it for Jerry, though he was gradually to gain glimmers which he could recognize as facts.

Once the door was closed, Ardlan's laugh took on a triumphant tone, for the benefit of two men standing by. Jerry recognized one, a pale, dry-faced man with deep eyes and long chin, who happened to be Trennick, Ardlan's trusted servant. The other was heavier set, dark-complexioned, and mustached. He gave Jerry a close scrutiny while being introduced to him.

Professor Ardlan introduced the darkish man as Vic Marquette, from the Federal Bureau of Investigation.

"You see?" queried Ardlan, turning from Trennick to Marquette, "I did send the telegram, as I thought, because Croft is here!"

Marquette nodded, while Trennick gave a worried stare. It was Marquette who spoke to Jerry.

"Did anyone follow you here from the Union Station?"

The query was blunt, and it seemed a criticism of Professor Ardlan. Marquette seemed to want a direct answer, so Jerry gave one which was truthful enough.

He simply said: "No."

Satisfied with the reply, Marquette shrugged and turned away from Jerry, who decided, therewith, to withhold further details unless specifically questioned.

"It's still too bad you named this address in a telegram," said Marquette to the professor. "Nobody is supposed to know you're here. You should have let me contact Croft for you."

"Exactly what I told Professor Ardlan," put in Trennick, "and I was sure, sir" - this was to the professor - "that you didn't send the telegram -"

Another shrug from Marquette indicated that he considered the matter closed. But it wasn't so to Jerry. He was quite convinced that Ardlan hadn't sent the telegram, not only because of the professor's penchant toward absent-mindedness, but because the telegram in Jerry's own pocket did not match the one described. It had told Jerry to come to the World Wide Cafe, not to this obscure address.

There was only one answer: someone else had probably wired Jerry; perhaps the bulge-browed man, which would mean that he or some of his associates spoke English, as well as their peculiar, unidentified language. They had brought Jerry to the World Wide Cafe to waylay him before he reached this address.

It was possible that they did not even know where Professor Ardlan was.

How did that bring in The Shadow?

Jerry pondered his own mental question and came to the conclusion that The Shadow was someone who had been watching the group of curious linguists, and seeing them go after Jerry, had taken a hand to stop them.

But only The Shadow could have given the cabby this address, which meant that The Shadow knew much about Professor Ardlan, as well as where the scientist was located.

Those were things that Jerry ought to have told Vic Marquette. There was a reason why he didn't. It was because Marquette happened to speak first.

"I'M glad you're here, Croft," said the Fed. "According to Professor Ardlan, you're the one man he trusts -"

"I trust Trennick, too," insisted Ardlan, clapping his hand on the servant's shoulder. "But each man to his duty. Croft is my assistant in scientific matters, while Trennick attends to my personal affairs."

"Getting to the point, Croft," continued Marquette, "I'm here to make sure that the professor's invention is quite safe. He insists that it is, because Trennick is on watch. But I have no proof" - his tone was emphatic - "that there is an invention in this house!"

"I've shown you the room!" boomed Ardlan. "Down in the cellar, where I keep my Neutralizer -"

"But how do I know what's in the place?" demanded Marquette. "Maybe you're keeping a hippopotamus downstairs, or maybe nothing at all! I've asked Trennick; he doesn't know. He's seen the outside of your strong room, like I have, but not the inside."

Jerry smiled.

"The professor does have an apparatus that he terms the Neutralizer," he declared. "I have seen it, Mr. Marquette, and can assure you of its existence."

"Seeing is believing," reminded Marquette.

Turning to the professor, Jerry suggested that he show the Neutralizer to Marquette. At first, Ardlan was loath to agree, but at last he gave the nod and they went down to the cellar, with Trennick following. They came to a steel door which had a combination lock, like a safe. Ardlan crowded himself in front of the combination, so that not even Jerry could watch him operate it. When the professor opened the door, Jerry noted that the metal was only a sheeting, that the door it covered was of wood.

Marquette started to enter, but Ardlan held him back. He insisted that neither Vic nor Trennick step across the threshold; but he allowed Jerry that privilege.

In the strong room, resting on a table, was the strangest contrivance that it had ever been Marquette's lot to see. Trennick, too, stared open-mouthed, for he had never been privileged to look at the Neutralizer before. Jerry, however, had seen the thing often.

Its center was a squarish box, not unlike that of a radio cabinet, except that it had a greater variety of knobs and dials, at least two dozen of them. The front was about four feet square, though the cabinet was less than that in depth. A row of lights, of different colors, ran along the top of the cabinet, and there were two diamonds of bulbs - red, yellow, green and blue - at each side.

Even more curious were the devices that topped the cabinet. They looked like small megaphones turned upside down, and they were drilled with holes. Each was capped with a glass bell, and in each crystal dome was a tiny fan, aimed downward. A chromium-plated bar ran along the tops of these bells, serving as a support for the axis of each fan.

The cabinet itself was flanked with cylindrical tanks about the size and appearance of small fire extinguishers, except that they were made of glass. Each contained a liquid, and the colors varied, from jet-black, through green and amber, to a smoky-white. These upright tanks, which formed two columns of four each, had pipes that led into the cabinet.

PRESSING a switch, Professor Ardlan caused the lights to glow; those along the top flickered, but the diamond groups remained constant. Another click, and the fans began to whir in the glass bells, producing a sucking sound from within the inverted funnels. Ardlan tapped the odd-shaped stacks that topped the cabinet.

"The Identifiers," he explained. "They sort gases and classify them, automatically. The lights will then register."

Marquette rubbed his chin; Ardlan noted it. He stepped toward an old-fashioned gas jet in the corner of the windowless room; then shook his head.

"Not necessary," he said. "It would be too much trouble as a mere demonstration. Just step over, Jerry, and breathe close to the Identifiers. I am not sure which is the proper one, but we shall soon see.

Jerry complied. He was breathing against the third funnel in the row of eight, when the flicker of the lights stopped. Two colors remained along the top: yellow and blue.

"Carbon dioxide," said Ardlan. "Watch."

He manipulated a switch at the left, until only yellow and blue shone from the diamond at that side. Going to the right, he repeated the process. When he turned a central knob, two vents popped open, one in the middle of each diamond, and the buzz of new fans came from within the cabinet.

Jerry kept on breathing as the professor gestured, but it was no use. Though Ardlan had stepped away from the cabinet, the vents closed suddenly and the diamonds glowed anew with all four colors, while the lights at the top flickered again.

The professor was pointing to one of the tanks at the side of the cabinet; Marquette observed that its liquid had bubbled.

"Enough, Jerry," said Ardlan. "Don't get yourself out of breath." He turned to the door. "Mr. Marquette, you have seen what my Neutralizer does. It sucks in gases, identifies them, and provides a vapor that neutralizes them."

"With any gases?" inquired Marquette.

"It could," returned Ardlan, proudly, "if I made it intricate enough. But I have confined it to known forms of harmful and poison gases, some of which are odorless and difficult to detect.

"Those large tanks in the corner" - he pointed to them - "contain such deadly gases as carbon monoxide and phosgene. I have experimented with all of them, along with chlorine and mustard gases. I regard them as playthings."

He was coming to the door, bringing Jerry along. Marquette, still looking at the tanks in the corner, gave a nod and said:

"I suppose that's why you keep the room locked."

"No," returned Ardlan. "I am more concerned about my Neutralizer. Look!" He stepped back to the cabinet, where he had already turned off the switches, and pressed two catches. As he tilted the device forward, the top lifted and showed the interior - an array of pipes, fans, wires, and coils, with dry-cell batteries perched on special shelves.

"Entirely self-contained," declared Ardlan. "And all the plans for it" - he was tilting the cabinet back with one hand, while he tapped his forehead with the other - "are locked right here. It would take me hours, perhaps days, to go over the mechanism, should anyone meddle with it. The misplacing of even a single wire would put it entirely out of order. That is why I allow no one to touch the Neutralizer."

MARQUETTE started upstairs with Jerry, while Trennick waited for Ardlan to lock the door. Drawing Jerry into a small parlor, the F.B.I. man asked:

"How long have you known the professor?"

Jerry replied, "A year or more."

"Did he ever let you handle the Neutralizer?"

"No,", replied Jerry. "My work is research. I dope out chemical formulas for neutralizing compounds."

"He had the machine before you met him?"

Jerry nodded.

"Tell me," asked Vic, narrowly. "Had he been working on perpetual motion before he started this thing?"

The inference was plain. Marquette thought that the professor was a crackpot, despite the recent demonstration, which in itself meant nothing, because the machine could have been rigged to produce the result automatically.

Behind the thought was Vic's mistrust of the professor, which was reasonable, considering Ardlan's eccentric ways.

Smiling at Marquette's doubts, Jerry insisted that he, at least, had faith in Professor Ardlan; but, therewith, he resolved to make no mention of his adventures here in Washington.

He doubted that Marquette would have any regard for the opinion of a man who talked of enemies who spoke an unknown tongue, and a friend in black who had fought them off and then vanished like a ghost. He didn't suppose that Marquette could believe in the existence of such a person as The Shadow.

That was Jerry's mistake. Marquette did know about The Shadow. It was a mysterious tip-off from the being in black that had brought Vic to Ardlan's. Had Jerry mentioned The Shadow, Marquette would not have doubted his sanity. On the contrary, he would have placed more confidence in Ardlan's young assistant.

Marquette left soon after Ardlan came upstairs, and it wasn't long before the telephone bell rang. Ardlan answered it, and Jerry heard him hold a blunt conversation. Returning, Ardlan announced to Jerry:

"It was Rufus Bradwell. You remember him?"

"The millionaire manufacturer," nodded Jerry, "who wanted to finance your invention. Is he here in Washington?"

"Yes," said Ardlan. "On a matter of some government contracts. He made me another offer, Jerry!" The professor's voice became a confiding whisper. "Half a million dollars for my Neutralizer, as it stands!"

"You turned it down, of course."

"Of course!" Ardlan leaned back and boomed a satisfied laugh. "My invention is for the benefit of all mankind, not as a thing of profit for Bradwell. Here is news, Jerry" - again it was a whisper. "The official test is set for the day after tomorrow."

Trennick was in the doorway. The dry-faced servant spoke remindingly to the professor.

"You wanted to call Congressman Anderton, sir -"

The professor laughed again.

"Anderton called me this afternoon, Trennick," he said. "Have you forgotten so soon? It is your memory that is at fault, this time."

Trennick retired, apologetically, closing the door as he went. Once in the hall, however, the servant no longer looked forgetful. Instead, his usually dull face was shrewd, as he sneaked to the telephone and dialed a number.

When a voice answered, Trennick spoke words that Jerry would have appreciated had he been present to overhear them, though he would not have understood them.

"Li alvenis sendangere," undertoned Trennick, "sed il rakontis nulo. Diru al mi, cu il evitis vin?" ("He arrived safely," undertoned Trennick, "but he said nothing. Tell me, did he avoid you?")

Trennick was using the same language as the men in the World Wide Cafe! He was being understood, for the reply that came from the receiver clicked away in the same tongue. Then:

"Ci tio estas grava," declared Trennick. "Illi estas preta provi la aparato. Morgau nokte estos nia fina okazo malebligi iln." ("This is important," declared Trennick. "They are ready to test the apparatus. Tomorrow night will be our last opportunity to stop them.")

Hanging up the receiver, Trennick took quick cat-footed steps along the hallway when he heard the creak of the parlor door. He was gone, into the kitchen, when Professor Ardlan and Jerry Croft appeared. They stopped at a table in the hallway, where Jerry had left his bag. He opened it to give Ardlan the sheaf of formulas.

Another door was opening, but it did not creak. It was the front door, which the professor thought was securely locked; it had been, until a few moments ago. Through the crack of the door, The Shadow saw Ardlan take the formulas; he could also hear a slight clatter from the kitchen.

"Trennick is preparing you some supper," the professor told Jerry. "He is thoughtful and faithful. I shall take these down to the laboratory, and return later. I feel quite safe, Jerry, now that you are here, along with Trennick."

The front door closed; its lock turned noiselessly under the probe of a special key provided from the other side. As far as The Shadow had seen and heard, all was well in the abode of Professor Ardlan.

How Trennick's unsuspected treachery was to change the situation, only the future could reveal - unless The Shadow, man of many methods, could gain his inklings elsewhere!

LATE the following afternoon, Jerry Croft took a cab from near the professor's house and rode to an apartment hotel nearer the center of Washington, keeping sharp outlook along the way. He felt it safe enough to be at large, since nothing untoward had occurred since the adventure along the Potomac River.

It was better, too, that Jerry should make this trip than the professor - which was the only other alternative. Better, too, because Ardlan wasn't in the right mood to call on Congressman Howard Anderton, who was the object of the visit.

From things that Ardlan had told Jerry in the morning, Anderton must have found the old professor to be quite a Tartar; in fact, Jerry wondered how they had gotten together at all. With the test of the Neutralizer finally decided upon, it would not do to let Ardlan ruin his chance on the last day, so Jerry had gladly accepted the assignment.

Congressman Anderton had a little office in his hotel suite, where he received people after hours. It was not much more than a reception room, where a young man, apparently Anderton's secretary, was on duty. Jerry gave his name and was shown into a study, where he met the congressman.

Anderton was as big a man as Ardlan, but bald, instead of shaggy-haired. His face, though stern, was pleasant enough and his handshake warm.

"Glad you came, young man," announced Anderton. "I've had a deuce of a time with that professor friend of yours. Wish he wasn't from my congressional district. Yes, I actually do. Sometimes, I almost think he's crazy. You'll meet a man soon who really believes that he is."

Jerry didn't ask about the man in question. He merely wanted to know about the test.

"We'll hold it at the proving grounds," declared Anderton. "Ardlan says the apparatus is effective within a radius of thirty feet, outdoors as well as indoors, so we'll have the test outdoors, to let people look on. We're going to use goats. Souse them good with some poison gas and let the professor show that he can save them."

There was a chuckle from the door. Jerry looked to see a tall, rugged man whose square face wore a smile, though it wasn't exactly a pleasant one. Somehow, those features looked familiar, with the grizzled hair above them.

Jerry remembered why, when Anderton introduced the visitor as Rufus Bradwell. Once Jerry had seen Bradwell when he called on Ardlan, but had not been introduced to him.

"So you're going to let the witch doctor have a try," chuckled Bradwell, referring to Ardlan. "He'll have to use plenty of hocus-pocus along with that mechanized brainstorm of his, or it will be tough on the goats. When is the test to be, Anderton?"

The congressman hesitated; then said:

"Tomorrow afternoon. We aren't announcing it publicly, though, because Ardlan preferred otherwise."

"He has a lot of crazy notions."

"I am afraid that he has." Anderton turned to Jerry. "Frankly, Croft, the professor has been a nuisance. For example, he insisted that Congress appropriate a million dollars before it was even tested, as a guarantee that it would really be put in use."

"He feels that it's a human benefit," said Jerry, "but he also told me that he was willing to take your word that the government would go through with it; if it worked."

"And would donate it to all the world," added Anderton, "so that peoples of all nations could be protected against the worst forms of chemical warfare. Don't forget that part of it."

"I know," smiled Jerry. "Ardlan said he would take your word for that, too."

Bradwell inserted one of his unpleasant laughs.

"A million dollars," Bradwell ridiculed. "Why, I wouldn't give another five thousand for the other half share!"

AT Jerry's surprise, Bradwell explained. He said that he had loaned Ardlan five thousand dollars to start work on the Neutralizer, two years ago. He had letters to prove it, containing the statement that he, Bradwell, was entitled to half of whatever profits the device should bring.

Of course, if Ardlan chose to give the invention away, that would leave him owing Bradwell five thousand dollars, nothing more. But there was another angle to it.

"We agreed to develop the device," stated Bradwell. "If Ardlan doesn't, I can. I have some of his earlier plans, and basically, the thing has merit. But I think that Ardlan has gone off the track, as he always does. So I've put other men to work along the same plan. Perhaps they will succeed if Ardlan does not."

Jerry couldn't readily believe that Ardlan would have given anyone the rough plans of his earlier work; but he knew that there were things the professor had never told him. Moreover, Bradwell's statement, considered logically, fitted with something that Ardlan had said the night before; something in keeping with the professor's usual way of mixing matters.

The offer of half a million dollars hadn't sounded plausible, but now Jerry could reconcile it. If Bradwell already held a half interest, and Ardlan figured the government would spend a million dollars, that meant that the professor's own share was worth a half million.

Probably Bradwell had merely requested that Ardlan let him handle the whole thing, which would lead Ardlan, in his none-too-rational way, to consider that he had received an offer of half a million dollars.

"All I ask is this," said Congressman Anderton, wearily. "You produce the professor at two o'clock tomorrow afternoon, Croft, and have him bring his invention. I'll bring the goats, though he ought to be able to produce them, too. He's got my goat, and Bradwell's, and a dozen other people's, I suppose!"

Smiling at Anderton's jest, Jerry was still trying to figure out Bradwell. Obviously, the millionaire was trying to disassociate himself from Ardlan, at the same time claiming that the professor owed him something. Jerry was beginning to wonder just how much the invention, if really practical, might be worth to a far-seeing businessman like Bradwell, when Anderton brought up another point.

"I can understand Ardlan's fear of enemies," said the congressman. "If news of his invention spread too far, it might cause him trouble.

"There are certain governments that would prefer to keep poison gases as an effective offensive weapon, and they wouldn't care to have the Neutralizer get into circulation as a defensive measure. We know for a certainty that such nations have agents operating in this country. They may be the enemies that Ardlan talks about."

Jerry doubted that Ardlan was worried about foreign spies. The idea was too rational for the professor. But Jerry's own experience with men who certainly were not Americans gave potency to Anderton's statement. Jerry, himself, intended to be on guard.

About to leave, Jerry paused as a girl came through the door. She was very pretty, and trimly dressed, and Anderton introduced her as his daughter, Ruth. She was about nineteen, and worthy of the admiration that she seemed to expect, though Jerry didn't give it.

He appreciated her sparkling blue eyes, brown hair, and saucy lips, but classed her as a trifle snippy. He could tell that she was spoiled, too, from the proud way in which Anderton received her.

As for Ruth, she perched against the edge of the desk and looked directly at Jerry, as though to say that she was pleased because an eligible young man had chosen to visit her father.

The glance that she gave toward Bradwell was her way of classing him as a dodo. Maybe she thought that Bradwell didn't guess it, but Jerry could tell that he did.

SHAKING hands with Jerry, Anderton turned to his daughter to say, almost apologetically:

"Sorry, Ruth, but I have to discuss business with Mr. Bradwell."

"You do!" Ruth finished the exclamation with a pout, then turned to Bradwell. "But I'd been counting on you, Mr. Bradwell, to take me downtown in your car to the Club Fiesta. You said you would, you know. You have taken me there before."

"I know," said Bradwell, gravely. "My car is waiting, Ruth, with Winstle at the wheel. He is a fine driver -"

"And you expect me to ride alone?" Ruth interrupted, in horror. "Why... why" - she stared at her father, then looked pleadingly toward Jerry - "I never heard of such a thing!"

She might just as well have shouted what she wanted, as far as Jerry was concerned, and Bradwell, for that matter; though Anderton, the indulgent father, was quite deaf to such wiles. Jerry saw Bradwell smile.

"You should have let me finish," admonished Bradwell. "I was about to say that I was providing you with an escort, too. Your father's friend, Mr. Croft, will be very glad to accompany you to the Club Fiesta in my car."

Slipping from her angled position against the desk, Ruth took Jerry's arm and waved a good-by to her father, who was nodding that it was quite all right. Bradwell gave Anderton a reassuring glance, and undertoned:

"I'll see them downstairs and speak to Winstle."

Bradwell did exactly that, but when he came upstairs again, he stopped in the reception room. He had noted that the secretary was gone, and Bradwell wanted to use the telephone. Getting the number he wanted, he spoke in a low voice:

"It worked... Yes, just the way I wanted it... No, there's plenty of time. Winstle is stopping for gas just around the corner. Oil, too. He can stall five minutes, maybe longer. The girl won't give Croft a chance to argue -"

"Yes. Before they get to the Club Fiesta. We've got to play it safe... Croft wants to get back to the professor's. He'll shake the girl by that time... The rest are with you?... Good! Get started."

While he talked, Bradwell was watching Anderton's door. On that account, he couldn't see the outer door of the apartment itself. It had opened and a man was standing on the threshold; he preferred to hold his steady pose, rather than ease the door shut. It was perfectly safe, since Bradwell was looking the other way.

Had Bradwell turned, which he didn't, he would have recognized the arrival as Lamont Cranston, a wealthy New Yorker and a friend of Congressman Anderton.

Tall, with a masklike expression on his hawkish countenance, Cranston watched impassively, hearing every word of Bradwell's conversation. Even its abrupt ending did not perturb the intruder, for he, like Bradwell, heard the creak from beyond Anderton's door and noticed that the knob was turning.

Away from the phone, Bradwell fairly bowled into Anderton as the latter was stepping from the study. In so doing, Bradwell created the impression that he had hurried back without stopping on the way.

It was during that encounter that Cranston closed the outer door. Disentangled from Bradwell, and accepting the grizzled man's apology, the congressman looked across the reception room, then glanced at his watch.

"I rather expected Cranston," he told Bradwell. "I guess I was mistaken. He always keeps his appointments punctually. He must have said that he was coming tomorrow, not today. You've met Cranston, of course. A remarkable chap!"

More remarkable than either Anderton or Bradwell supposed. Lamont Cranston, the hawkish gentleman who had so suddenly switched appointments, happened to be The Shadow!

JERRY CROFT wasn't allergic to women. He was simply choosy, and within reasonable lines. He liked them closer to his own age than nineteen, for Jerry was twenty-five. Moreover, he considered brains at least as valuable as beauty. He felt that Ruth Anderton was as short on one as she was long on the other.

Winstle's delay at the gasoline station proved a nuisance, and so did Ruth. Jerry couldn't very well hurry Bradwell's chauffeur, and the girl dodged his suggestions to that effect. She said that there wasn't any hurry to get to the Club Fiesta. Jerry would like the crowd, of course, because Ruth did, but she rather preferred a longer while with Jerry before arriving there.

It was simply a case of getting properly introduced, though Jerry doubted that Ruth's definition of the term fitted with his own - or her father's.

Her questions were definitely to be approved; she wanted to know what Jerry did, where he'd been, and other things that she could mention to her friends when she and Jerry met them.

But the way she snuggled closer and kept lowering her tone, so that Winstle wouldn't overhear, was an indication that she wanted to tow Jerry in as a new trophy, to impress her friends with her ability at using glamour in a practical way.

Jerry didn't care to be a souvenir. If someone was to take someone else somewhere, he preferred to be the taker. Maybe that would have suited Ruth even better, but Jerry hadn't come to Washington to cut a figure among the local debs.

He was thinking of humanity at large, and specifically concerned with Professor Ardlan. Tomorrow, his mind would be on goats. He intended to keep it clear, until then.

Ruth could have her friends at the Club Fiesta, and to humor her Jerry was willing to let her think that he was anxious to meet them. She'd get her surprise when the limousine arrived there; maybe sooner, if circumstances so ordained. Telling people off was one of Jerry's habits, when they provoked him too much. He liked such opportunities.

Jerry was going to get one.

The limousine slowed for a traffic light that happened to be green, though it turned red very shortly. Jerry observed Winstle's lapse in not going through, and wondered about it. He didn't puzzle long.

Another car wheeled up beside the big one. A couple of men jumped out and grabbed the limousine door. Winstle began a protest; a third man arrived and poked a gun at him.

Jerry started to open the door on the right, to find that a fourth man had pushed up from the sidewalk. The fellow was masked, but he didn't show a gun. He was reaching for one, as he growled:

"Don't make a fuss, Bradwell. We're snatching you, old moneybags!"

Putting his foot right in the middle of the man's chest, Jerry drove him so far across the sidewalk that the fellow seemed to jar the bricks of the wall he bumped against. He sat down, but he had his gun in hand, so Jerry figured the other direction was better. He turned, to see the first pair of thugs gripping Ruth and stifling her screams.

She was yanking at their masks, and they were too busy handling her to pull their guns. Up front, Winstle was grappling with the only man who did have a weapon handy.

Lunging shoulder first, Jerry bowled Ruth right out of the car and sent the two masked men sprawling ahead of her. They took wide dives, and at that moment Jerry saw a cab, its door open. Its driver had seen what was going on and was offering a route to quick escape.

Remembering the co-operating cabby of the night before, Jerry picked up Ruth and thrust the gasping girl into the yawning door. As he jumped in, the cabby slammed the door and was away, just as guns began to bark.

Jerry managed to look back, despite Ruth's stranglehold. The thing he saw amazed him. Those guns had started to spurt wildly after the cab, but had suddenly changed direction.

Four thugs were going into action against a fighter whose ability was sufficient to make Jerry's flight with Ruth unnecessary.

The Shadow!

FROM a rather amateurish preliminary, the thing had become a professional bout, though Jerry Croft wasn't on hand to witness the transformation. One thug had luckily spotted The Shadow springing from an arriving car and had yelled the word to the others, emphasizing it with his gun, before The Shadow's taunting laugh was given.

Now, with mockery as a challenge, The Shadow was blazing back, scattering his foemen as they fired their hasty shots. Here, under the changing glow of the traffic light, he had an opportunity to deal with enemies more effectively than on the night before. But Winstle spoiled it.

Only one man had gotten back into the other car. If Winstle had held his ground, the others would have been trapped flat-footed. But Winstle stepped on the gas and sent Bradwell's limousine roaring through the traffic light.

The fact that it was red didn't bring a collision. All other cars in the vicinity had darted away. The thing that counted was the fact that Winstle took three thugs along on his running boards - two from the street, the third, the half-groggy man, from the sidewalk.

To witnesses, it appeared that Winstle didn't want such passengers, but The Shadow knew better, for Winstle was Bradwell's chauffeur and this was Bradwell's game. Moreover, the speed that Winstle made with the big car, his deft way of rounding the nearest corner, where a hotel offered cover, showed that he wanted to save his pals.

In his own car, a coupe, The Shadow was in pursuit, but he saw the futility of the chase. This was a great spot for a getaway, thanks to the crisscross of avenues. Once clear, Winstle would simply let his passengers drop off, then come back to claim himself a hero.

What The Shadow wanted was a car that didn't know that it was being trailed. Doubling back on his course, he picked up one.

It was the car that had brought the thugs that Bradwell ordered. Its lone occupant, the driver, thought that Winstle had carried The Shadow off on another track.

His mask pocketed, the fellow was acting as though his car was just another of the lot that had scattered during the fray. He was driving timidly along an avenue, taking care not to violate traffic regulations, and The Shadow fell in behind him.

There were other cars, quite a few of them, in the forming procession; which turned the pursuit into a slow-motion chase. After several blocks, the car ahead turned into a numbered street, then into a lettered one, and finally headed into a parking lot.

The Shadow did the same, but in an inconspicuous fashion, while the one attendant on the lot was checking in the first car.

The unmasked thug started through a little alley in back of the parking lot, and The Shadow followed. He saw the man enter the rear door of a small office building, and waited until a light appeared on the second floor.

Taking advantage of the darkness, which had settled before The Shadow left Anderton's hotel, the cloaked trailer entered the building and found a stairway. Getting into the office was easy. The man ahead had left the door unlocked.

The Shadow saw him plainly in the light of an inner office, part of a two-room suite. From the outer darkness, The Shadow reached the door and overheard the telephone conversation that the fellow was making to someone, who could only be Bradwell. The unmasked thug had a roundish face, but he looked quite tough, particularly because of the twist he gave his lips when he talked.

"Hello, chief... Yes, this is Hortland. Thought you'd be back home... Yes, we got Croft out of the way... No, he wasn't hurt, and neither was the dame, but he won't get back to the prof's for an hour, anyway. He fell for the cab stunt -

"We had trouble, though - The Shadow... Yeah, he showed up and went after Winstle... Don't worry, the boys will drop off at the right places... Winstle? He'll be a hero, like Croft. The whole thing is a set-up, the way it stands... Me? Don't worry. If I get in a jam, I'll call the right guys -"

HORTLAND was in a jam and knew it, as he hung up the receiver. Chance blackness had entered the room and encroached upon the desk, and the fellow was lucky enough to spot its silhouetted form just before it slid away. It was rarely that The Shadow approached too close, but on this occasion he did.

Perhaps because it didn't seem to matter at the moment. Hortland had told Bradwell that he could call the right guys - in a pinch, and "right guys" were usually made to order for The Shadow. If it meant bringing back some of those who had sped away with Winstle, so much the better.

Back in darkness, The Shadow waited. He saw doubt reflected upon Hortland's face. The fellow wasn't quite sure that he had spotted indications of The Shadow. Nevertheless, he picked up the telephone and dialed it.

The undertone that Hortland used was quite a contrast to his speech with Bradwell. Watching for the silhouette, Hortland was sure that The Shadow, if present, couldn't overhear. Still, Hortland was playing the thing doubly safe. He didn't know that The Shadow, by choosing a new angle, was hovering almost in back of him; but if he had, he wouldn't have cared.

Hortland was using the same language that Jerry had heard at the World Wide Cafe!

"Heh!" he began. "Malga!.. Yes; Hortland!"

That part was obvious; Hortland was announcing himself to someone named Malga. But the rest of his speech had the veil of the language that Jerry had not identified.

"La Ombrajo estas ci tie," spoke Hortland. "Malantau mi... Donu iu liberigi min... Rapidu.... Kio?... Ili sekvis lin!... Ili atendas la sonorilo... Mi sonorigas gi, venigi lin -" ("The Shadow is here," spoke Hortland. "Behind me... Send someone to aid me... Hurry... What?... They followed him!... They await the bell... I shall ring it, to bring them -")

HORTLAND was lowering the receiver with one hand, and The Shadow couldn't have seen the movement of the other, for it was hidden by the man's body.

Beneath the desk, Hortland's thumb was pressing a button which produced no sound within the office. It was connected with an outside bell that could only be heard in the hall.

Yet The Shadow wheeled as if actuated by the signal that he could neither see nor hear. Driving through the darkness of the other office, he was at the hallway door as it bashed inward to admit a surge of men, who were thrusting revolvers ahead of them.

As he went, The Shadow uncloaked a second gun, a mate to the one which he had used to cover Hortland. He sledged blows with both weapons.

Hortland heard the impacts as The Shadow's automatics cracked revolvers from the hands that gripped them and landed, like metal cudgels, upon the invaders themselves.

Twitchy-lipped, the round-faced man came full about, his hand fumbling his own gun as he pulled it from his pocket. For Hortland recognized the mistake by which he had himself warned The Shadow, and thereby ruined this snare.

The Shadow understood the language that Hortland had used across the telephone. In repeating aloud the statements of Malga, the man at the other end, Hortland had given The Shadow a cue to the presence of the invaders!

HARD and swift were The Shadow's blows, yet with those strokes his own impetus seemed to fail. The very men who were half staggered by his thrust were carrying him back into the darkened room, spinning the cloaked fighter as if he had been a thing of straw.

Others were shoving in behind them, and to all, it seemed that they had met The Shadow's drive and stopped it, until the last of them were in the darkness.

Then, they felt The Shadow whirl away and knew that he had tricked them. Bringing them clear into the room, some with gun hands numbed, others with aching skulls from which The Shadow's blows had glanced, the cloaked fighter had cleared the path for his own exit.

From various spots, the invaders turned to aim at the door; but, though there were four of them, not one was in a suitable shape to cut him off.

The rule didn't apply to Hortland. He had a grip on his gun and was aiming it toward the upright oblong of light that represented the outer doorway. As a sweep of blackness chopped across that space, Hortland jabbed shots in quick succession. Above the barks of the revolver came an evasive laugh that might have come from anywhere.

Anywhere, except at the fatal doorway!

The Shadow hadn't made off through the exit, to pick up Hortland's bullets on the way. The thing that had sliced into the doorway was the door itself, slammed by The Shadow. He preferred the darkness of the outer office, and was bettering it by cutting off the light from the hall.

He was still in the room with the blundering invaders, and Hortland was among them. They had planned a trap for one, The Shadow; he had turned it into a snare for five!

As Hortland sprang back into the inner office and frantically yanked the cord of the desk lamp to put himself in darkness, he heard shouts from the outer room. Shouts so loud, that they drowned his own as he tried to stop the others from uttering them.

"Evitu la pordo!" ("Avoid the door!")

"Restu proksimi de la fenestroj! Ili estas pli sendangere!" ("Remain near the windows! It is safer!")

"Ni kaptos La Ombron -" ("We will capture The Shadow -")

Those were words The Shadow understood, though only Hortland knew it. Things happened very rapidly, to the surprise of the recuperating invaders. Wheeled full about, The Shadow hurled himself suddenly upon them at the other side of the room, where they were coming up from hands and knees beside two windows that opened into the count below.

They tried to spread, and stumbled across tables and chairs that they couldn't see, losing guns as they went. But they were clever enough to turn their blunders into good account. They began to throw the furniture that blocked them, and in that desperate effort, they bothered The Shadow more than they could have with guns.

Chairs and tables were big missiles. The Shadow could not escape them by dropping close to the floor, for they bounded all about him. He saw the shapes against the slight light from the window, and maneuvered handily enough to avoid them, but he necessarily had to dodge wide.

Nor did the chucking process give away the positions of the foemen, as gun stabs would have. Inadvertently, these enemies were using the best possible system. None of them stayed long in one spot, as they would have had they paused to fire. Needing more furniture, they went after it by the simple process of darting about, pell-mell.

That made them impossible targets, considering that The Shadow, himself, was also on the move, avoiding the articles of furniture that were constantly coming his way.

There were more shouts in the language they all knew, each man telling the rest to keep to the task. The missiles were increasing in size as they lessened in number, for the furniture was breaking apart against the walls. A table top smashed a window, carrying away all the glass, and the clatter gave someone an idea.

"Mi iras al la tero!" called a voice. "Gi estas pli amike ol La Ombro!" ("I am going to the ground," called a voice. "It is more friendly than The Shadow!")

POUNCING upon the shouter, The Shadow caught him close by the windows and flung him back upon the others, as they surged in the same direction. They were lashing about with heavy clubs - legs from tables and chairs - which had a longer reach than The Shadow's guns. But they were after the windows, not The Shadow. Smashing more panes from the sashes, they went rolling through.

The Shadow jabbed shots to stop them, but his gun hand was gripped by the man who had bounced back at him from the human wave. The Shadow saw the fellow; he was the man with the bulgy forehead, who had trailed Jerry Croft. Therefore, he could not be Malga, to whom Hortland had made the telephone call. The fellow was merely the head of the strong-arm crew that Malga controlled.

The bulgy man was putting up a frantic fight, despite the fact that his left arm was bandaged. With others plopping through the broken windows like parachute jumpers, he wanted to do the same, since it had been his own idea.

He slashed at The Shadow with a handy chair leg, wrenched free to the window sill, and toppled across. Instead of hauling him back, The Shadow heeled the other way.

From the outer door came a shaft of light. The Shadow had counted three men going through the window; this fellow was the fourth. One other must have chosen the way through the hall, and the man was logically Hortland. To The Shadow, he was more important than any of the rest, for Hortland had talked to both Bradwell and Malga.

Half through the doorway, Hortland saw the last of the rescue crew go rolling through the window. Still gripping his gun, Hortland hoped that he would see The Shadow following them and get another chance at the fighter in black.

Hortland found his chance, but not as he expected it. Blackness itself came swooping in upon him from an unexpected angle.

That blackness was The Shadow!

Bodily, The Shadow bowled Hortland out into the hallway, shoving the fellow's revolver upward so that its spouting shots were as harmless as those of a popgun. Hortland tried to slug instead, and each time, The Shadow sent his arm jerking upward like a pump handle.

During that process, he was shoving Hortland along the hall in zigzag fashion, from wall to wall, each jounce knocking more breath from the fellow. Hortland's collapse was imminent, as they reached the stairway. The Shadow let him hover over the edge, then caught him to haul him back.

He knew that the thought of a fall wouldn't be pleasant to Hortland, otherwise the fellow would have chosen the window route, like the members of the so-called "rescue crew."

Sagging weakly in The Shadow's clutch, Hortland panted words in English:

"I'll... tell all I know! Let... let me live! I'll talk... I'll spill everything -"

The Shadow was drawing him back from the stairs, when Hortland chanced to look below. A new glitter came into his eyes; with it, he showed a burst of strength. Pulling away from The Shadow, Hortland gave a lunge toward the stairway, gleefully shouting a name:

"Kurd Malga!"

A gun spurted; its bullet found Hortland's chest. But the gun was not The Shadow's. The shot was fired from below.

Malga, the man whose name Hortland had cried, was actually here in person, to learn how his crew had made out. Having heard Hortland's promise of a full confession, Malga had decided to dispose of the man who knew too much.

SPRINGING to the stair top, The Shadow saw Malga below. He wanted to get a good look at the man with the ill-sounding name, for tonight was not the first time that The Shadow had heard of Malga. The fellow was notorious as the hidden leader of an international group who worked for whatever country made the highest bid.

When The Shadow took a look at men of Malga's ilk, it was always along the barrel of an automatic. On this occasion, he applied the usual rule.

Below was a squatty man, standing with a smoking revolver; a vicious personality whose face looked like a grinning skull, except that it was dark, not whitened. Though deep in their blackish sockets, Malga's eyes had an evil glimmer; his lipless mouth was drawn in a death's-head grin. His gun, too, was lifted; he was looking for The Shadow.

Muzzles spurted from both ends of the stairway, as The Shadow and Kurd Malga began their duel. It was the sort that should have been settled instantly, according to whichever gained the split-second advantage, for The Shadow was a sure shot, and Malga rated as the same. But this was a duel with an obstacle that rendered first shots futile.

The obstacle was Hortland, bouncing in his crazy, halting tumble down the stairs. Mortally wounded by Malga's shot, the squealer was going through a convulsion that carried him from banister to wall and back again, in crazy pitching fashion. The Shadow had to side-step to avoid that flaying, downward perking form, and so did Malga. Both fired wide.

Again their guns blasted, as each made a shift. Malga's was first, because The Shadow knew his rival had miscalculated the direction of Hortland's next pitch. Hardly had Malga changed his aim, before The Shadow did the same.

Though Hortland had gone in the direction The Shadow expected, a slump of the tumbling body twisted it about, spoiling The Shadow's aim at Malga, too.

Crouched low, Malga jabbed a third shot upward, as Hortland took a long, unguided lurch for him. That shot was very wide, for Malga made an ungainly shift to deliver it. The mistake saved him, for The Shadow's blast, coming at the same moment, was placed where Malga should have been, but was not.

With those blasts, the duel ended.

Darting away under cover of Hortland's final lurch, Malga reached the court, to hasten after the four men who had plunged from the second-story window. By the time The Shadow reached the ground floor and looked from the outside door, his squatty, skull-faced rival was out of sight.

As an urge to Malga's flight, came the blare of police whistles and the wail of approaching sirens. This battle, almost in the heart of Washington, was bringing in the law.

Turning to the slumped form of Hortland, The Shadow lifted the man's head, which twisted crazily from a neck disjointed by the plunge down the staircase. Dying, Hortland might have forgotten his willingness to talk, so The Shadow reminded him emphatically, speaking in the language that Hortland had used earlier.

"Vi diris ke vi rakontos -" ("You said that you would tell -")

It was useless. Hortland's eyes were staring glassily from his flabby head. The man who knew too much had died too soon. Kurd Malga had at least seen to that before dueling with The Shadow.

Letting Hortland's dead form slump to the floor, The Shadow faded into the outer darkness. Gliding swiftly across the courtyard, he melted from the glaring flashlights of arriving police; who promptly stumbled upon what remained of Hortland.

By then, The Shadow was gone into the night, bound to another destination, where he knew - too well - that trouble threatened because of the designs of Rufus Bradwell and Kurd Malga.

Through Hortland's death, The Shadow had lost his chance to link definitely those two; but as to the game at stake, he had no doubt.

The Shadow's destination was the forgotten house where Professor Urlich Ardlan lived, sole possessor of an amazing, yet unproven invention that might be a boon to thousands of helpless persons throughout the world.

To save that boon for humanity had become The Shadow's cause!

AT the very time when The Shadow was starting for Ardlan's, Jerry Croft was thinking in terms of the professor, too. Jerry and Ruth were still riding in the cab which had so luckily plunged them out of danger, and the driver was darting around every corner which came his way.

The fellow was acting as if a batch of pursuing cars were close behind him, which didn't make sense to Jerry. Looking through the rear window, Jerry saw no one in pursuit, and began to figure what the answer really was.

Smart of Bradwell, Jerry decided, to have this cab show up just at the right time. He couldn't have let Winstle do a run-around all over Washington with the limousine, for that was something that could be traced back to Bradwell later.

Ruth was clinging close to Jerry, bothering him every time he turned to look back through the rear window. Her eyes had their saucy gleam, for she was enthusiastic, rather than frightened, over the adventure, and the mad ride that was still in progress.

"How thrilling," she murmured, "the way you fought them, Jerry, and brought me away! I don't care if they do overtake us. You handled them before, and could again!"

She spoke as if she believed it, but Jerry took it for flattery. There wasn't anything to worry about; no pursuers were on the trail, and Ruth knew it, for she had looked through the rear window, too.

Jerry was tired of the hero stuff, and considered himself a dupe, instead. The animosity he felt toward Bradwell, who had shoved him into this thing, was sufficient for Ruth to have a share.

If it hadn't been for the girl, Jerry would have stayed at the scene of battle. Instead, he had done just what Bradwell figured: he had seen to Ruth's safety ahead of everything else. She wasn't responsible for that part of it, but if she had minded her own business and gone to the Club Fiesta alone in Bradwell's car, instead of demanding an escort, Jerry would by now be at the professor's.

In fact, he intended to be there very soon.

The cab driver had finished his run-around and was bound toward the city limits, in a direction which Jerry was sure must be the opposite from Ardlan's house. Pushing Ruth aside, Jerry told the fellow to stop being foolish. When the cabby looked as though he didn't understand, Jerry put his hands through the front window and tightened them around the fellow's neck.

"Forget the gas and try the brake," urged Jerry. "If you don't, I'll see that you wreck this buggy, and it will hurt you just as much as it will us! Maybe more!"

Unable to breathe, the cabby was already handling the wheel in wobbly fashion, and the prospect of a head-on smash with a car from the opposite direction made him agree with Jerry. He applied the brakes, and Jerry relaxed pressure accordingly. The cab pulled over to the side of the avenue.

"Honest, I don't know who those guys were!" the cabby panted. "Someone, slipped me a ten-spot and told me I was to help a guy and a dame out of a jam. He told me where I was to be, and said to keep dodging, and then head for the limits after you got into the cab."

"Remember what he looked like?"

"No." The cabby shook his head. "He got into the cab where I was parked; then out again. All I heard was his voice."

Jerry didn't inquire if the man had a bulgy forehead, since the cab driver hadn't seen his face. He did ask if the man had talked with a foreign accent, or used any words in a language that couldn't be identified.

Shaking his head, the cabby said that the man had seemed like an American and had talked in very good English.

Giving the professor's address, Jerry told the cab driver to start there and make it fast. As they were turning around in the avenue, he asked if the Club Fiesta would be out of the way, and the cabby said it wouldn't be.

Jerry told him to stop there first, and as a result, he listened to a barrage of stormy protests from Ruth all during the ride.

Wherever Jerry was going, Ruth intended to go, too. If he thought it would mean more danger, and therefore wouldn't take her, he could compromise by stopping off at the Club Fiesta, where she still wanted him to meet her friends, more than before. Saying nothing until the cab stopped at the night club, where a doorman stepped up to meet the cab, Jerry suggested that Ruth get out. She said that she wouldn't unless he did, first, and gave an imperious gesture to emphasize the statement.

The gesture was her mistake. Jerry took Ruth's waist, hauled her across in front of him, and added a neat push that sent her out into the arms of the astonished doorman. Before Ruth could find her feet, Jerry pulled the cab door shut and ordered the driver to continue to his destination.

ALREADY, Professor Ardlan was receiving visitors. They had arrived while The Shadow was busy with battle and Jerry in the midst of undesired flight. There were three men in the party, and Ardlan had let Trennick admit them to the parlor, for they looked harmless.

One, their spokesman, called himself Mr. Crumpf; he wore glasses that were connected to a gold chain running to his vest, and he talked with a very sad, reproving tone.

Crumpf's companions were about on a par with their spokesman. Both were drab and serious-faced; they shook their heads in tune to Crumpf's remarks.

"We cannot tolerate cruelty to animals," insisted Crumpf. "We are a committee opposed to such practices. You must not harm those poor goats, Professor Ardlan. If you will not listen to our protests, we shall take legal measure to prevent you!"

Crumpf's companions turned their headshakes to nods, at mention of legal measures.

"Who said I'm going to hurt the goats?" boomed Ardlan. "Nothing is going to happen to them!"

"But we have heard that they are to be subjected to poison gases -"

"Under the protection of my Neutralizer," interrupted the professor, "which makes harming them impossible."

Crumpf still was uncertain.

"We must have proof," he finally said. "Proof that this device of yours really works. We've heard arguments like this before, Professor Ardlan, and we always like to put a question of our own. Why, if all is safe, do not humans accept such tests themselves, instead of placing the burden upon helpless, ignorant animals?"

"The goats aren't my idea!" stormed Ardlan. "I'd undergo the test myself, if I didn't have to demonstrate the apparatus. It's just that people won't trust me, but goats will. Perhaps you gentlemen would be willing to substitute for the goats?"

"Perhaps we would," rejoined Crumpf, "if we knew more about your Neutralizer, as you term it."

"Then come along."

Ardlan told Trennick to show the visitors the way downstairs, but the professor did not immediately follow. He stepped to the front door, opened it, and saw a car parking across the way.

As he observed the man who alighted, Ardlan gave a beckon; leaving the door unlatched, he closed it and went downstairs. Trennick and the visitors were standing near the door to the laboratory.

Working the combination in the usual fashion, Ardlan opened the door, but held back Crumpf and the latter's companions. Gesturing for Trennick to enter, much to the servant's surprise, Ardlan followed him halfway across the room, then paused to whisper:

"You will find a gun in the desk, Trennick. Have it ready!"

Smiling, Ardlan turned to the group at the door. They started to enter; again, he waved them back. "My demonstrations," boomed Ardlan, "are always given under the proper auspices. I think it proper for everyone to show credentials. Turn around, gentlemen, so that I may introduce you to Mr. Marquette, of the Federal Bureau of Investigation."

They turned, to see Marquette standing with a drawn gun, displaying a badge with his other hand. It was Vic who had come from the car at the professor's beckon. Ardlan had been expecting him at the time when Crumpf and the others called.

"These gentlemen," Ardlan told Marquette, "claim they represent an animal-protection committee. Perhaps their spokesman - Mr. Crumpf - will be willing to show his own credentials."

"I have them," Crumpf acknowledged. "In my wallet -"

CRUMPF was reaching to his hip, which didn't strike Marquette as unusual, as many people carried wallets in their hip pockets. But instead of producing a wallet, Crumpf jerked out a gun and sprang for Marquette at an angle that avoided the Fed's gun.

One of Crumpf's companions yanked a gun, too, as he joined the drive toward Marquette. The third man pulled a revolver to cow Professor Ardlan.

Only Trennick was forgotten. Coming back to the door, the servant was carrying the gun that Ardlan had told him to get, but he was stopping, stupefied, as though he did not know how to use the weapon.

Crumpf and the fakers with him had scored an absolute surprise, as two hurled Marquette to the floor, and a third drove Ardlan to the wall, with Trennick merely standing by.

A surprise that might have meant death for the defenders, had not intervention come. It was the sort that carried challenge to all men of crime, which Crumpf and his companions were.

The challenge was a mocking laugh that came from the stairway, bringing the men who heard it full about.

None could defy that mirth and live.

It was the laugh of The Shadow!

TWO men had so far been mistaken: one was Professor Ardlan; the other, Vic Marquette. Both thought that Crumpf, the man with the gold-chained spectacles, and his drab-looking companions were spiritless individuals.

True, they had turned when trapped, but they had done so in a rattish fashion. With the situation suddenly reversed by The Shadow, the trio should have quailed.

They didn't; nor did The Shadow expect them to do so. He hadn't fallen into the error shared by Ardlan and Marquette.

He knew Crumpf for what he was - a tool employed by Rufus Bradwell to get at Professor Ardlan's invention; whether to destroy it, merely injure it, or simply learn its secret, were matters to be studied later. The case was obvious, considering that Bradwell had taken spectacular pains to remove Jerry Croft, the one man likely to see through the bluff put up by such visitors as Crumpf.

Certain it was that Crumpf and his pals were smooth and calculating workers; otherwise, Bradwell would not have hired them. At least, Crumpf was on a par with Hortland, and The Shadow could bear witness to Hortland's punch in a pinch. He knew instantly how Crumpf and the men with him would react when snared: they would attempt escape at any cost.

They did.

Crumpf didn't have to yell at the others. They were on the move as quickly as he. Marquette, Ardlan were forgotten. Three guns were swinging for The Shadow, shoved ahead of the men who held them, as all made for the stairs.

They wanted to blast the foe in black, and get past him. The double desire was shortening the range, giving them a better opportunity.

Professor Ardlan, flattened against the wall; Trennick, gawking from the laboratory door, considered The Shadow doomed. Not so, Vic Marquette.

Though flat on the floor, his own gun out of reach, Vic expected The Shadow to survive. He knew how the cloaked marksman could beat others to the shot; he was sure that The Shadow would, in this case, nick two out of three and take his chances on the last.

Instead, The Shadow did not fire at all!

His leap from the stairs was something phenomenal. One quick step downward gave him impetus; with the advantage of a higher level, he must have traveled close to twenty feet in the broad jump that he made - or would have carried that far, if he hadn't encountered human obstacles on the way.

In the time space that Vic had allowed for The Shadow to beat two marksmen, the master fighter had outdone all three, for his flying drive carried him right into the surging cluster and scattered them wide.

Floundering backward, the men thwacked the walls and floor, their guns tonguing upward to the ceiling. The Shadow was through them, and beyond, when they rolled to their feet and made a mad dash for the stairs, not bothering to look back. They had good reason to decide that flight came first.

The Shadow was after them, his triumphant laugh ringing in their ears, promising them something much more dire than mere sprawls, should he overtake them.

ON his feet, Vic Marquette was following The Shadow. So was Professor Ardlan, a few seconds later. In the time that Vic took to snatch up his lost gun, Ardlan acquired a weapon, too, by snatching his own revolver from the frozen hand of Trennick.

Ardlan took the additional seconds to boom an order at Trennick, telling the servant to close the laboratory door and turn the combination dial. Then, with long strides, the shaggy professor was hurrying after Marquette.

During the trip up the stairs, Vic realized the soundness of The Shadow's strategy. The cloaked fighter couldn't have risked shots at Crumpf and the others when they surged. Had they been apart, in a room, The Shadow's system would have been to shoot at two, crippling them, while making a quick-fading dodge as a prelude to his duel with the third.

But the hall below was narrow; clustered, the crooks were partly shielding each other. In addition, the stairs had been an impossible place for The Shadow to stage a fade-away. It seemed that every time Vic saw The Shadow in action, it meant another for the book.

Vic was to learn more, very shortly; it was unfortunate that he didn't foresee the fact.

The front door was wide when the Fed reached it, and the fugitives were outside, scattering across the street. The Shadow was taking a long bound down the front steps, his automatic poised as though deciding upon a target.

Marquette halted, intending to take one victim that The Shadow didn't; and Professor Ardlan, arriving, copied Vic's example.

Changing direction, The Shadow took a sudden dart between two trees. He wasn't after the nearest man; he was picking the most important fugitive, Crumpf. The Shadow fired, his laugh echoing with his shot.

Crumpf faltered, but did not stagger. The bullet had whined a half inch past his ear, enough to discourage anyone's idea of flight, which was what The Shadow wanted. His plan was to take Crumpf alive.

Vic's gun was talking now, but uselessly. He'd picked another man; too late. The fugitive was too far away and intervening trees too numerous.

Professor Ardlan wasn't shooting. From the way he squinted, he couldn't see very well in the darkness. The man that Vic failed to get reached a car some fifty feet down the street. Vic looked for the third man and spotted him.

Before Vic could aim, a young man sprang from an arriving taxicab and sprang for the third crook. He grappled with the fellow, trying to wrest away his gun. Marquette recognized the arrival as Jerry Croft and yelled for him to let the fellow go.

Jerry did, but only after a reeling struggle halfway to the waiting car, and it was only because Jerry tripped across the curb that he let the fellow get away.

Running beyond the trees, the fugitive reached the car and jumped into it. The car started, carrying the two men away. Marquette fired a few wild shots after it, and so did Jerry, for he had gotten what he wanted: a gun. He had taken it from the crook just before the spill across the curb.

With the fugitive car rounding the corner, Marquette thought of The Shadow; looking for the cloaked fighter, Vic saw him. The Shadow had overtaken Crumpf after that first shot, for Crumpf, the idea of flight scared out of him, had swung about to fight off the cloaked avenger.

They were grappling in what seemed a furious style, and Crumpf, to Vic's amazement, appeared to have the advantage. He was actually driving The Shadow ahead of him, back across the street toward Ardlan's front door!

IT should have occurred to Vic that such wasn't the direction Crumpf wanted; that, in reality, The Shadow was hauling Crumpf back with him, intending to toss him, exhausted and defeated, right at Vic's own feet. Vic was to think out that point later, and keep it for future reference.

For the present, Vic's only idea was to help The Shadow; and the same thing occurred to Jerry, on the other side of the street.

Jerry saw his opportunity and fired, winging Crumpf, who was on the side toward him. The Shadow wheeled Crumpf about, thinking that Vic wouldn't make the same mistake; but the Fed did. He gave Crumpf a second bullet.

To offset further folly, The Shadow gave Crumpf a lunge, hoping he would sprawl and thereby show that he was helpless. Crumpf staggered, which was enough for Jerry and Vic, but his reel was in the direction of the house.

Recognizing Crumpf, but not realizing the fellow's pitiable condition, Ardlan inserted another walloping slug from his old-fashioned revolver.

Crumpf collapsed in the middle of the front walk. Marquette dashed out into the street to commandeer Jerry's cab, and the young man joined him. Together, they sped away, hoping to overtake the other fugitives.

Professor Ardlan, stopping a few moments to look at Crumpf, continued as far as the sidewalk, but arrived too late to join the pursuit crew.

To all appearances, Crumpf was dead; but The Shadow had tried too valiantly to keep the man alive, to give up the last shreds of hope. He glided up beside Crumpf's coiled form; stooped, and lifted the fellow's head.

Crumpf's gold-chained glasses were gone, but they had only been part of his make-up. His gaze was clear, though he was coughing his last.

There was defiance in those eyes. The Shadow used the system that he had tried with Hortland.

"Vi venis al la domo," spoke The Shadow, in a low tone, "difekti la provo kio estas en la laborejo." ("You came to the house," spoke The Shadow, in a low tone, "to destroy the invention that was in the laboratory.")

Dying eyes still held their stare. Either Crumpf did not understand the language, or he was too obdurate to answer any questions, even from The Shadow. Again, The Shadow spoke, this time in English:

"It was Bradwell who sent you here?"

There was a glitter in Crumpf's gaze. His lips opened; then, between clenched teeth, he gritted:

"No... not Bradwell!"

The response did more than tell that Crumpf was familiar with English only. The denial was practically the same as "Yea," though Crumpf did not realize it. To really deny Bradwell's part, Crumpf should have shown no recognition of the name; but his fading intellect hadn't rallied to that point.

He was being loyal to Bradwell, who hadn't double-crossed him, as Malga had with Hortland. But loyalty, in this case, was a give-away.

At least, Crumpf's warped conscience helped to ease his death pang, for a moment later, his eyes went glassy and his head slumped, but his gritted teeth held an expression which might have been termed a smile.

THE taxicab was returning from a trip around the block, for Marquette and Jerry had found no sign of the fugitive car that had taken away Crumpf's two companions.

As Vic and Jerry joined Ardlan, The Shadow faded into the darkening shelter of the front trees. He watched them carry Crumpf's body toward the house, Ardlan hurrying ahead to call Trennick to help the others with the dead weight.

They were at the top of the steps when Trennick appeared. He helped get the burden into the parlor, then came back to close the front door.

Moving to the steps, The Shadow merged with the door's blackness. Finding the door still unlatched, he opened it a crack without having to trouble with the lock.

Vic and Jerry were still in the parlor, looking at the body. The Shadow saw Ardlan and Trennick, heard the professor speak to the servant.

"Did you lock the strong-room door?"

"Yes, sir," replied Trennick. "Immediately after you gave the order."

"Good!" Ardlan rubbed his hands warmly. "Our visitors failed even to see my invention. Tomorrow's test is certain to succeed, and you deserve a share of the credit, Trennick."

"Thank you, sir."

The Shadow let the door ease shut, because Trennick was turning to lock it. Gliding off into darkness, The Shadow gave a whispered laugh - a tone that might have been a knell for Crumpf, whose death was to be regretted, since he would have been more valuable alive.

But there was a tone of satisfaction in the final quiver of The Shadow's undertoned mirth. It certified Ardlan's opinion that all was secure for the coming test.

For The Shadow's easy glide, his pauses, proved that he did not intend to travel far. Instead, he was assuming a duty; he intended to patrol this neighborhood in person, and make certain that no new attempt would be made, by others, to complete the design at which Crumpf and his companions had failed.

UNFORTUNATELY, The Shadow's vigil did not include a watch within Ardlan's house, itself. He was leaving that to Marquette, Jerry and Trennick. But the first two were not keeping tabs upon the third.

Professor Ardlan had gone into the parlor to talk with Vic and Jerry. As a matter of course, Ardlan closed the door behind him.

It was Trennick's opportunity. Reaching the telephone, the servant dialed the same number as the night before; hearing the voice he recognized, he spoke in the strange tongue:

"Ili venis, sed ilia intenco trovigis... Mi restis en la laborejo en ilia loko... Lo Provo malsukcesos morgau -" ("They came, but their purpose was discovered... I stayed in the laboratory in their place... The test will fail tomorrow -")

As Trennick hung up, a sneering chuckle was audible from the descending receiver; it was identical with a tone that had similarly come across the wire to Hortland's office.

The tone of Kurd Malga, who had balked The Shadow by killing Hortland, and was confident that he had done the same through Trennick, who still lived.

BY noon the next day, reports of Ardlan's coming test had spread through official Washington and reached the newspapers. Congressman Anderton had ended a dilemma by making the facts public. As he put it to Cranston, who dropped into the apartment around noon, there had been no other choice.

"The professor wants a million dollars appropriated for the benefit of humanity," explained Anderton. "At first, he wouldn't hear of doing things any other way. My mention of congressional committees made no impression on him."

"What I did tell him" - Anderton gave a rather pleased smile - "was that the act of voting through an appropriation would proclaim the facts too soon.

"I argued that it would be better to prove the invention's merit, and deliver the apparatus to the government for safe-keeping. Afterward, the appropriation would come in due course - as I actually believe it will. Moreover, I see no reason why the war department would hesitate to give the device to other nations, as Professor Ardlan wishes.

"Our national policy is one of defense, and we have encouraged other nations along that line. America is opposed to war, and anything that can nullify the horrors of war should be extended to those who need it. My one hope" - he shook his head - "is that Professor Ardlan is not as crazy as he sometimes appears to be."

A scoffing voice interrupted. Rufus Bradwell had arrived, and the secretary had sent him into the study.

"You have only seen Ardlan in his milder moods," Bradwell told Anderton. "Like yourself, I hope that the test succeeds, but knowing Ardlan and his eccentric ways, I am short on confidence. By the way, Anderton, I brought Winstle up to the reception room. Do you want to speak to him?"

Anderton nodded, and Bradwell opened the door to call in Winstle.

This was The Shadow's first look at the chauffeur, and one glance told him that the fellow was a rat - a fact which Bradwell calmly ignored and Anderton failed to discern. However, when Anderton shook hands with Winstle, the chauffeur showed a modest manner, though in a crafty way.

"I really did very little, sir," said Winstle. "I fought off one ruffian and managed to get the car away, but I made the mistake of thinking that Miss Anderton was still safely in the car with Mr. Croft."

"They saw a cab and took it," explained Anderton. "Otherwise, they would have stayed with you. In any event, you drew the pursuers, Winstle."

Winstle started to say something, then glanced at Bradwell, as though taking a cue. The grizzled man clapped the chauffeur on the shoulder.

"You're going to drive us to the proving grounds, Winstle," he said. "That shows how much we think of you."

Soon after Winstle had gone, Ruth entered the study. The girl was jauntily dressed and her hair was freshly curled. There was no denying that she was attractive, though she would have described it as allure.

Her get-up was unquestionably for Jerry's benefit, because she passed by Cranston and Bradwell with a roving glance and looked questioningly toward her father.

"Isn't -" Ruth caught herself "- isn't the professor coming with us?"

"No," replied Anderton. "He and Croft are bringing the Neutralizer out to the proving grounds in a truck."

Without knowing it, Anderton had answered the question that Ruth really wanted to put: namely, why Jerry had not come. Bradwell looked toward The Shadow, who considered it good policy to supply the slight smile that suited the guise of Cranston.

THEY rode to the proving grounds in Bradwell's limousine, and as soon as they arrived there, Ruth strolled over to a parked truck and watched the driver open the doors in the back of it: She expected to see Jerry appear, but instead, a procession of goats came popping out.

They didn't merely go "baaaaa!"; they lowered their horns and made for the spectators, and Ruth joined the general scramble for safety. However, the goats were wearing ropes, and their keepers hauled them in before they damaged any of the throng.

The goats were dragged to the center of the flat arena and tethered around a great sack that hung from a high pole. The thing looked like a cross between a giant hornets' nest and a small balloon.

Soldiers measured the ropes, to make sure that the goats were within the required radius, and before they had finished another truck came through the circle of surrounding cars and rolled up beside the pole.

This time, Jerry did step out, along with Vic Marquette and a few other Feds. Ruth couldn't find a chance to speak to him, because soldiers were ordering the crowd back. From the truck, Jerry and the others brought the professor's famous invention, and unveiled it directly beneath the mammoth hornets' nest.

The soldiers checked the ropes again, to make sure that the goats were not close enough to ram the machine upon which their lives would soon depend.

In fact, the goats had become quite ludicrous in behavior, and even tried to butt the truck when it pulled away from among them, much to the amusement of the crowd. Merriment increased when Professor Ardlan arrived on foot and had to dodge between the bewhiskered creatures that were to help his test.

Sight of the shaggy-haired professor, zigzagging between the goats, was really very funny to everyone but Ardlan. When the crowd echoed the "baaaaa" of the goats, Ardlan showed indignation. Forgetting the goats, he glared at the people - and the throng quieted suddenly.

This was to be serious business. Maybe the lives of these very onlookers would some day be in jeopardy, hanging by the thread that Ardlan's invention represented. The newspapers had rushed special editions, and hadn't missed a trick in covering the possibilities of the gas Neutralizer; hence everyone was familiar with the purpose of the new invention.

Poison gas, most horrible of war weapons, would be a forgotten menace if this test went through. There would be one in every home, in every bomb shelter; they could be used in tanks, submarines, and other military conveyances. Hospitals would find them a boon in protecting the wounded.

The Neutralizers, as experts pointed out, would be far more than a substitute for gas masks. They wouldn't just protect people against poison gases; they would eliminate the gases, through neutralization.

This was of vital importance, considering that certain deadly gases, as yet little used in warfare, were known to be odorless and therefore dangerous before gas masks were put on, or after they were taken off.

The Neutralizer, according to Ardlan's claims, could detect such gases automatically, and not only proclaim their presence, but dispose of them. So it behooved the people who watched the test to show more sense than did the unwitting goats.

Standing by Bradwell's car, The Shadow watched the professor's preparations. Bradwell was chatting with Congressman Anderton, but The Shadow noticed that Bradwell's eye was occasionally on Jerry Croft, who had come over to the car. At first, it had seemed that Jerry intended to speak to Anderton, perhaps to make some pointed remarks that Bradwell might have understood. But Ruth had flagged Jerry, and was talking to him so ardently that he couldn't get away, much to his annoyance.

Maybe Jerry would have had a sharp eye for Winstle, too, had the chauffeur been around; but he was not. Winstle had run into some acquaintances - the chauffeurs of other cars - and had gone somewhere with them.

A LOUD-SPEAKER began to blare above the proving grounds, telling everyone to move back to a distance of at least fifty yards. Soldiers were putting the order into effect. As the loud-speaker lulled, The Shadow heard Anderton speak to Bradwell.

"They intend to use chlorine gas," said Anderton. "They tried a quantity this morning and made sure that it would not spread too far. There has been no increase in the wind since then, so the spectators will be quite safe."

"Does Professor Ardlan know what kind of gas is being used?" inquired Bradwell.

"Absolutely not!" emphasized the congressman. "He said that his machine will detect and eradicate any form of gas, so we are putting it to that test."

"But chlorine is a fairly common type of gas -"

"It makes no difference, Bradwell. As long as Ardlan does not know what gas is being used, he will have to be prepared for all."

"He appears to be ready."

Still surrounded by the goats, Ardlan had stepped back from his machine, which was now in action. Its hum, the whir of its fans, could not, however, be heard at that distance; nor did the lights show against the sun, though they were actually blinking.

The professor pressed a final switch, and turned about. Two soldiers made a path for him, by tugging back a pair of goats; then they conducted Ardlan toward the spot where Anderton stood.

The professor's approach gave Jerry his chance to break away from Ruth. He spoke a reminder to Ardlan:

"You remembered to press the automatic switch?"

Ardlan nodded.

"Yes, Jerry." Then, to the others: "It was the last thing you saw me do. Ordinarily, I manipulate the machine during a test - first letting it identify the gas, then setting it accordingly. The automatic device was a later improvement, but it works, as you shall see."

A long cord had been carried from the gas bag atop the pole, to a spot where a cluster of army officers stood. The Shadow noticed foreign uniforms in the group, knew that the visitors were South American officers, at present visiting Washington. They had been invited to view this important test, which might prove so great an asset to the defense of the Western Hemisphere.

A stout colonel pulled the rope. A ripcord opened and the big bag spread, delivering a gush of greenish smoke that spread like a blanket over the tethered goats. The animals did not like the deluge; there was a chorus of a dozen baas, as the goats were lost amid the spreading fog of green.

Then, as the gas crept outward like an ugly monster, spreading itself in search of further, prey, the noise from its midst ended.

Professor Ardlan was staring with wild gaze, as the gas slowly dissipated. Even his short-sighted vision was capable of viewing the result that the other onlookers saw. The blanket had leveled to a mere layer along the ground, no more than a foot in depth, but no goats were visible.

The first signs of them came only when patches of gas cleared entirely away. Then, as the last shroud of the deadly stuff was gone, all the goats were visible.

To a goat, they were lying on the ground. The Neutralizer was still operating, for its blinking lights had shown against the background of the chlorine mist. Yet the gas had annihilated every creature within its range!

WITH a bellow of unbelief, Ardlan stumbled out toward his machine. Jerry leaped after him to draw him back, for the ground was not yet safe. Savagely, the professor tried to keep ahead, and it took two soldiers to help Jerry restrain him. Anderton turned to Bradwell and said, in a sorrowful tone:

"I think it is time for us to go."

Bradwell agreed. His face looked as long as Anderton's. Perhaps The Shadow might have noted that Bradwell's gloom was not genuine, but it happened that The Shadow was not about.

Winstle had just returned, and The Shadow was moving swiftly in the direction from which the chauffeur had come; though, as Cranston, he managed to keep his speed from being too apparent.

"Come, Ruth," said Anderton, to his daughter. Then, looking about, he questioned: "Where is Mr. Cranston?"

"He said he was going to meet a friend," the girl replied, "and ride back to town with him."

Ruth was looking toward Jerry, who was still engaged in humoring the professor. Ardlan was gesticulating, tearing at his shaggy hair, and to all appearances would be a real problem for some time to come. So, reluctantly, Ruth stepped into the limousine, along with Bradwell and Anderton.

Some cars were already leaving the proving grounds, and it was toward one of those that The Shadow hurried. He wasn't in time to overtake it, for it spurted through a gateway out to the road. But he was in time to spot two faces in the front seat.

One, that of the driver, was the grinning, skullish countenance that belonged to Kurd Malga; the other, bulgy of forehead, belonged to the man who served as leader of Malga's strong-arm crew!

There were two more of the tribe in the back seat, but The Shadow did not care about the odds. All that he needed was a car, and people who noticed Cranston saw him turn suddenly, and spring into a coupe that a young man was driving from the proving grounds.

The young man happened to be Harry Vincent, one of The Shadow's secret agents, posted here for just such an emergency as had occurred.

Other cars, however, intervened between Harry's and the gate. The delay made it impossible to overtake Malga and his men. Easing back in the seat, The Shadow spoke in Cranston's quiet tone.

"You saw what happened, Vincent," he remarked. "This does not mark the end of our interest in protecting Ardlan's invention. We may say that our cause has just begun."

There was a grim touch to those calm words, which told Harry that he could expect special instructions as to the part he was to play. So far, The Shadow had played a lone hand, seemingly to perfection, yet his efforts had not availed.

It would require more hands than one to get to the bottom of the riddle which had resulted in the failure of Ardlan's great invention; for the ways of the opposition were many. They had spoiled today's test, despite their apparent failure of the night before.

With such men in the game, neither Professor Ardlan nor his invention would be safe until the perpetrators of secret crime were rendered helpless.

The Shadow knew!

JUST after dusk, Jerry Croft entered the World Wide Cafe and took a table in the corner. This was the second time he had been in the place, but this evening he did not expect to meet Professor Ardlan.

Jerry had just left the professor at his house; he had come here hoping to meet the men that he had found instead of the professor, on that first evening in Washington.

That the man with the bulgy forehead and his companions were in some wise responsible for the failure of Ardlan's Neutralizer seemed quite obvious to Jerry. As obvious as the fact that Rufus Bradwell, the grizzled millionaire with the too-wise smile, must be the man behind the whole dirty game.

Things had looked all right last night, when Crumpf and a couple of stooges had come to grief trying to get at the Neutralizer; but it was Jerry's opinion - and one that seemed indisputable - that Crumpf and his pals had merely been a blind.

Their visit, Jerry decided, must have been intended as a failure; because, by their fluke, they drew suspicion from the real effort that had actually put the invention out of working order.

If Jerry had ever seen Kurd Malga, the man with the grinning death's head, he would have credited, or discredited, the fellow with having done the job, for Malga looked the part of the arch-conspirator that he was. Yet, there would still have been the riddle of how Malga, or anyone else, could have gotten at the professor's invention.

It never occurred to Jerry that the thing might have been an inside job, engineered by Ardlan's faithful servant, Trennick.

None of Malga's strong-arm men was around the World Wide Cafe, though Jerry looked everywhere. He listened for snatches of the strange language that he had previously heard, but no one was speaking it. Even the tawny-faced waiter was absent; either it was his night off, or, more likely, he had quit the job.

A chair scraped beside Jerry; he turned with a start, reaching for the gun that he had been carrying since last night. His expression changed from challenge to exasperation.

Ruth Anderton was sitting down beside him.

Superficially, the congressman's daughter had a mood to suit every occasion, with an extensive wardrobe that matched. Last night, she had tried to impress Jerry by being coy, convivial and, finally, trusting.

Not having clicked, she had used a new technique this afternoon - a straight girlish pose, tending toward the outdoor type. She hadn't made a dent; to Jerry, she had simply been part of the scene, like the lamented goats.

Her present course was to appear confidential and mature. Stunningly gowned; Ruth was a creature of loveliness, her eyes dancing, her smile friendly instead of saucy. Her snub nose was offset by the tilt of her chin, and, in all, Ruth was putting on an excellent act. But it was an act and nothing more, as Jerry could tell, even after so brief an acquaintance.

Ruth was out to make a conquest, and was using every wile. It was plain that she wanted to break down Jerry's reserve, or indifference, whichever it might be, before she began to cast new eyes upon eligible young men who came her way. Hence Jerry, quite sure that he saw through the game, did not feel at all honored by Ruth's attention.

Nevertheless, he covered his annoyance and became quite polite. He accepted Ruth's pretext that she had just chanced into the World Wide Cafe, though he was quite sure that the restaurant did not belong on any fashionable route that she and her society friends followed.

He'd tried to indicate that his lack of interest was actual; and since Ruth wouldn't accept that answer, Jerry would have to try some other plan. Courtesy seemed the best opening move.

FINDING that Jerry had a welcoming smile, Ruth tried her confidential tone.

"I thought surely that you would come to father's apartment," she said. "He doesn't blame you because the test failed. He only blames Professor Ardlan."

To Jerry, that was as bad as if the blame had been placed on himself, but he didn't say so. He foresaw that if he let Ruth talk long enough, he would eventually have cause to tell her off. So Jerry inquired, quite blandly:

"Your father called Professor Ardlan?"

Ruth nodded.

That told Jerry something else. Jerry had told Ardlan that he was coming to the World Wide Cafe, though he hadn't mentioned why. Ardlan must have informed Anderton, which was how Ruth had located Jerry.

"What did the professor have to say?" asked Jerry, casually. "Anything important?"

"I don't know," returned Ruth. "He was busy trying to get his silly invention working, as if it ever could! Dad talked mostly to a Mr. Marquette, who happened to be there."

The news pleased Jerry, even though its bearer did not. He wouldn't have left Ardlan at the house if he hadn't known that Marquette was due. In Jerry's opinion, Trennick wasn't enough protection for Ardlan.

Had Jerry known of Trennick's affiliations, he would have realized that the servant was no protection at all. But Jerry's discovery of that point was to come later.

Most important, in Jerry's mind, was the fact that Professor Ardlan was overhauling the Neutralizer, testing its series of complicated wires and gadgets, one by one.

On the way back from the proving grounds, Ardlan had become himself again, and stated, with a positiveness that impressed Jerry, that someone must have switched portions of the integral mechanism without actually injuring it. In a case of straight sabotage, the professor argued, the Neutralizer would not have operated at all.

Such logic could not be disputed. Neat tampering, of a sort that even Ardlan had not recognized, smacked of Bradwell's work. To Jerry, it also pointed at others - the man with the bulgy forehead and his company - who, despite their strong-arm tactics, were subtle enough to use a mysterious language whenever they conversed in public.

Jarring Jerry's reflections came Ruth's voice, which someone else might have likened to a lovely coo, but which, to Jerry, was as unwelcome as a raven's croak.

"You haven't ordered dinner yet," the girl said. "