Thus, The Shadow counted six who had returned. He calculated that four had fallen in the battle wherein he had sided with the deputies, and had been left dead on the shore at Grendale's, along with Barcla.
While the wounded men were being helped from the steel lake monster, The Shadow gained a good view of the craft. Its motor was still running, with a sighing hiss.
The Shadow noted low lumps, like ventilators, in front of the cockpit and recognized their purpose.
They were intakes, sucking in air to a hidden device that separated the component elements. Similarly, there were valves along the water line near the bow of the boat, that took in water. Near the stern, bubbles were drifting from outlets, accounting for the foamy wake that The Shadow had seen on other nights.
The Shadow recalled a story of a crazed inventor, now dead, who claimed that he had created a hydro-vapor motor which combined oxygen from the air with water, to form an explosive chemical combination, H2O2. Such an invention had been doubted on the grounds that the apparatus would have been highly improbable.
Evidently it worked, for this ship fitted with the story. The lake monster's cigar-shaped hull housed a floating laboratory which could combine air and water into a vaporized fuel. However complicated the mechanism, once working, it could continue almost indefinitely, and the motor had added qualities unstated by its inventor: those of speed and silence.
Criminals had acquired it, diverting the device to their own purpose. Confident that the mystery ship would never be recognized as a vessel, they had kept their game concealed until The Shadow arrived at Lake Calada. Even yet, they supposed themselves safe, here in their subterranean lair.
MOVING behind the men with the lights, The Shadow was working toward the crevice in the rocks. His course was slow, for he was dripping wet and had to avoid sloshing sounds. He wanted to enter the lair itself before the crooks arrived.
Deep in the split, The Shadow found his path barred by a formidable door of metal, that had a large keyhole. Bullets could settle that lock, but it might take a gunfull of them; and the sounds would be heard on the other side. It would be better, The Shadow decided, to follow Rufus and the others through.
An automatic drawn from its waterproof holster, The Shadow started to retrace his steps. As he neared the watery vault where the lake monster was berthed, he found that he was too late. Rufus and the others had come along the landing rock, flashing their lights ahead of them.
Supporting one of the wounded pals, Rufus was displaying a large key. That, plus the fact that Rufus hadn't come ahead alone to get help for the wounded, indicated that all the crooks had gone on the night's expedition.
Had The Shadow blasted the door with bullets, he would have brought no opposition from within. But that course had become too dangerous, with Rufus and the rest on their way here. The only thing to do was settle the crooks first.
The Shadow gave them chance for life.
His laugh reverberated suddenly through the vaulted chamber, unearthly in its stridence. It seemed a voice of mockery from a tomb, in a setting well suited for it.
Walls, dome, even the water's surface caught the taunt and threw it back. It might have been a laugh from the sleek lake monster, for the echoes made it impossible to locate.
The Shadow expected consternation from the crooks. They wouldn't guess that he had gone past them at the boat. By rights, they should have picked the channel under the arch as the place of the laugh's origin, and turned in that direction. Once scattered, looking for battle from the rear, they would be harmless.
But the thugs saw The Shadow.
Rufus, trying to twist for cover, was grabbed by his wounded pal, who wanted the light extinguished. In their struggle, they staggered toward the cleft where The Shadow stood. The beam turned toward the black-cloaked fighter; Horace gave the shout that told the others where real danger lay.
Even the wounded men showed agility, as the whole crew dived for sheltering rocks, bringing out their guns. They were shooting with frantic determination, as The Shadow wheeled for shelter of his own.
Rufus was quick enough to reach the very edge of the cleft. He yelled for the rest to help him trap The Shadow.
Back by the metal door, The Shadow was jabbing shots that held the crooks where they were. His fire was spasmodic. He knew that he faced a bullet shortage, if this fray kept up. Lights were gone: a drive out toward the enemy marksmen would be dangerous, except as a last resort.
They were copying The Shadow's measure, making their shots occasional, confident that their cloaked foe would drop if he tried to squeeze out through the cleft. But their fire would come closer the moment that The Shadow ceased to return it. For that reason, he could not spare time to blast the stout lock of the door behind him.
The Shadow was trapped; but the crooks did not guess why he had allowed himself to be.
Half a dozen boats had reached the stone-jutted channel that fronted Indian Rock. The occupants of those boats could hear the hollow blasts of gunfire. They could locate it, too, coming from within the mighty rock itself.
Fitful reflections of light came from the archway at the water line.
Men were working their boats toward that inlet, using searchlights to study the entrance. Their trouble was how to get through; none of their boats were low enough.
AMONG the arriving craft was Scorpio's speedboat. Lois had seen it at the dock and had used it to join the chase, with Denwood as a passenger.
Other boats had crowded through the stony channel toward the rock; by that delay, Lois and Denwood were able to aid The Shadow. They saw the thing upon which he depended.
Reflected gun spurts were no longer visible at the water-line arch because of the searchlights. But Lois and Denwood saw the same tokens higher up, from a crack that no one else noticed. They shouted to the boats ahead; when an obliging searchlight swung toward them, Lois pointed upward.
During the next five minutes, men were busy scaling to the fissure that the girl indicated. All the while, the muffled reports of guns came at paced intervals. The crooks were keeping up their policy of wearing down The Shadow; he was letting them continue, confident that it would produce their own disaster.
The catastrophe came. The thugs suddenly heard shots from a new direction. Turning, they saw guns spurt from a slit in the front dome of the vault. Men had spotted their flashing guns and were giving them a barrage.
Danger of exhausted ammunition applied to the crooks. Bullets were nicking the rocks about them. They had only one course: to rush The Shadow.
They came, en masse, the wounded with the rest. Then all were staggering out again, met by fire that was quicker than their own. They were dropping guns; some were stumbling into the water, as they tried desperately to reach their only refuge, the berthed ship.
Too late. Splashes near the arch told that men had dropped through from the crevasse above. Flashlights began to gleam, as the newcomers found the ledge that formed a shore. The crooks, already crippled, hadn't a chance against that insurge. The Shadow's expected supporters had arrived.
Reaching the metal door, The Shadow used his remaining bullets to ruin the lock. They weren't quite enough; he hammered steadily with the butt of an automatic to complete the work. Haste was no longer needed; still, The Shadow always counted minutes. He had spent at least a dozen, from the time that he had arrived on board the lake monster.
Through the door, The Shadow followed passages with his flashlight. He encountered other barriers, set in narrow places, but they were comparatively flimsy. Reaching a squarish room, The Shadow saw a flight of rough- hewn steps. He called below.
A shout answered him; he recognized the voice as Harry's. Another voice joined in; The Shadow could hear the rattle of doors as he dashed down the steps.
Then the clatter increased; a third voice added its bellow. It was louder than the others, for it came from the nearest cell; there, The Shadow's light showed Niles Rundon.
Smashing the locked gate with his heavy automatic, The Shadow went on to the next. He finished it in quick time, and slashed at the third. Rundon was stumbling for the steps, followed by Harry and finally Carradon, when The Shadow turned about.
From above the steps, he saw the wavering flicker of a flashlight. Shouting to the rescued men to watch out for an attack, The Shadow sped to overtake them. He heard yells as he reached the top of the steps.
