Loud yells denoted the voodoo men were taking the trail of Doc and his friends. Pine-knot torches flamed. They cast fitful, dancing shadows. The hot white rods of modern flashlights mingled with them.
Random bursts were loosened frequently from machine guns. These never did anything more annoying than shower Doc and his five men with bark, twigs, and leaves.
"Kinda reminds me of the big scrap in France!" Monk's mild voice was more than ever a surprising contrast. It hardly seemed possible the boisterous, animallike bellowings he emitted while in action could come from the same source as the sleepy, soft words.
"Well, the wind is at our backs!" Renny announced. "So what?"
"So this!" Doc pointed.
Before them reared the white, ghostly stub of a dead tree. Lightning had apparently shattered it long ago. The bark was gone. Cracks gaped in the pale wood. Patches of foul green fungus spotted it.
Doc quickly wrenched away a section of the lifeless trunk. A cavity was revealed. The trunk was hollow.
The cache held a number of boxes about the size of apple crates. One of these had been opened.
"I investigated," Doc explained. "Two of those boxes hold ordinary hand grenades. The others contain a supply of poison-gas grenades. It's the same kind of deadly gas the Gray Spider has twice sought to use on us. The wind will carry it over our foes."
"Glory be!" enthused Monk. "And that ain't the half of it! There's gas masks along with the stuff!"
The masks were swiftly hauled out. Monk, Renny, Long Tom, Ham, and Johnny donned them. But Doc Savage delayed.
"We will use the gas only as a last resort," he pointed out "After all, the fiendishness of these swamp men is largely due to one man—the Gray Spider. If we can get the master devil and the group of his important lieutenants, which he calls the inner circle of his Cult of the Moccasin, it will be unnecessary to do any wholesale killing. The other swamp men, freed from the Gray Spider's sinister influence, can be reformed."
Doc now advanced a few yards. He carried a hand grenade—one which did not contain gas. He plucked out the firing pin and lobbed the metal egg into the morass.
It exploded with an ear-splitting roar.
The blast caused silence to seize momentarily upon the low hill. The voodoo men were surprised, uneasy.
Into the void of quiet rolled Doc Savage's words. Now, more than ever, was the amazing quality of penetration apparent in the bronze man's voice. It seemed to gather some of the elusive nature of Doc's strange trilling sound, for, without being in the least loud or blaring, it filtered to every part of the hill.
"We have the gas and the masks!" Doc told the voodoo men. "To attack us will mean death for you! The wind will sweep the gas to you!"
AT this threatening declaration, the silence deepened. It became an uneasy pall.
Suddenly, an order crashed among the voodoo men.
"He's right! We can't rush them. Draw back into the swamp! We'll get them if they try to leave the hill!"
It was the Gray Spider speaking.
Doc's men exchanged puzzled looks.
"Glory be!" gulped Monk. "Did you notice—"
In giving the command to his voodoo followers, the Gray Spider had been forced to lift his tone to a yell.
He had forgotten to disguise his voice!
"I’ll say I noticed it!" Renny snapped. "That voice is familiar! I've heard it somewhere!"
"So have I!" Monk said mildly. "But I can't place it."
Renny offered: "Maybe Doc can!"
With a start, Renny bit off his words.
Doc had vanished! There had been no sound. They had noticed no stir in the pale moonlight that splattered through the canopy of swamp vegetation. Yet the mighty bronze form was no longer in their midst; he had slipped away as if on a moonbeam.
"Doc has gone after the Gray Spider alone!" Ham clipped.
Ham had made a good guess. At the precise moment he spoke, Doc was two-score yards away. The russet metal hue of his skin, the dark color of his garments, rendered him nearly invisible, even when he crossed patches of moonlight.
At the foot of the hill, the swamp tangle reared like a wall. A great leap sent the bronze man upward. His case-hardened fingers found a limb. The branch bent some under his great weight, but made little noise.
A voodoo man near by saw the foliage sway. He got the most fleeting glimpse of a figure that might have been a metallic bat. There had been no noise. The swamp man blinked, thinking a dark, night-flying moth was before his eyes. When he looked again, the strange vision was gone.
He galloped off, muttering of voodoo curses and evil spirits. He couldn't understand what he had seen.
Nor would he have believed his eyes, had he observed the flashing speed with which a Herculean bronze man traversed the aлrial lanes of the interlaced swamp vegetation. No squirrel or anthropoid jungle dweller could have shown more uncanny ability.
Sometimes creepers draped in tree-tops parted under the weight of the bronze giant. But he never fell far before his sure fingers found fresh grip. Nor did these breath-taking drops seem to bother him in the least.
Deep in the morass, the voodoo man had stopped to catch his breath.
Suddenly a voice came out of the murk beside him.
— vare ees de Gray Spider?" it asked. "Me—I got plentee important message fo' heem."
The voodoo man thought it was one of his fellows. "Dunno vare Gray Spider ees! Him go away—not tell anybody vare to!"
The silence of a tomb followed. The voodoo man got curious. He investigated. He found no trace of whoever had spoken.
Several other swamp men had almost identical experiences. No one discovered who had addressed them in the debased jargon of their kind. Not one dreamed it was the mighty bronze man they feared.
For Doc Savage was seeking the Gray Spider—seeking with all his great resource of muscle and brain—and seeking in vain!
Chapter XV. THE BUZZING DEATH
Periodic, vicious little storms were sweeping the voodoo hill in the great swamp. The storms were lead—driven by the machine guns of the voodoo men. The little devils completely ringed the hill around.
Trees sheltered them. Foliage concealed them. An army of forty thousand men would have had trouble stamping them out. When danger threatened one particular group, they had but to fire and lose themselves in the steaming, cankerous morass.
Doc and his five men were in a state of siege upon the hill. They had ripped planks off the shacks of Buck Boontown's settlement, and used them to scoop out gun pits. In these they had installed the machine guns which they had taken from their erstwhile swamp guards.
Employing the same planks, they had rigged substantial dugouts—a precaution that proved highly worth while.
"Listen!" Monk barked. "There's a plane coming!"
The craft soon swept into view. It dived on the hill. Crude bombs, fizzing fuses attached, dropped overside.
Exploding, these threw up great fountains of mud and vegetation. Thanks to the dugouts, no harm was inflicted upon Doc and his men.
"Get that crate!" Doc directed. "It may come back with more efficient bombs!"
The rapid-firers snarled in chorus. Ragged patches appeared in the wings of the plane. The craft banked away. Apparently it was not seriously damaged. Now it was lost to view, flying very low.
But a few minutes later, the sound of the engine suddenly ceased. A short silence, a gruesome whistling of wind through flying wires—and a resounding crash!