Suddenly Doc discovered a glowing cigarette end in a fern top near the thick jungle.
"Watch it!" he called. "The light might show Kar our position!"
"Im sorry!" called Oliver Wording Bittmans voice. A moment later, the cigarette gyrated downward, to burst in a shower of sparks.
Doc and his men were tired they had not slept a wink the night previous. Although the satanic noises within the crater were as fearsome as on the night before, they were becoming accustomed to them. Noises that made their ears ring and icicles roll down their spines now worried them no more than passing elevated railway trains bother a dweller in the Bronx.
But Doc had developed a sort of animal trait of sleeping with one eye open. He heard a faint noise. He thought he saw a light some distance away.
Later, he was sure he detected a distinct, dragging noise very close!
The sound stopped. Nothing immediate came of it. Doc dropped off to sleep. Too many monsters were prowling about continually to be bothered with one noise.
A loud shuffling beneath their trees aroused him again. He listened.
There seemed to be scores of great beasts below!
"Hey!" yelled Monk an instant later. "Some darn thing is eatin on the bottom of my tree!"
To Docs keen ears came the sound of grinding teeth at work on the base of Monks fern. Then big incisors began on his own tree!
Capable bronze hands working swiftly, Doc picked off a fragment of his own shirt. He put a flame to it, got it blazing, and dropped it. The burning fragment slithered from side to side as it fell. It left a trail of sparks. But it gave light enough to disclose an alarming scene.
A colony of monster, prehistoric beavers had attacked them!
The creatures were about the size of bears. They had the flat, black, hairless tails of an ordinary beaver. But the teeth they possessed were immensely larger, even in proportion.
A determined fierceness characterized the beasts. Although they made no snarlings or squealings, the very rapidity of their angry breathing showed they were bent on accomplishing something.
And that was the destruction of Doc and his men!
DOC SAVAGES gaze moved quickly to one side. He had remembered the dragging noise heard earlier. He sought the spot where it had ended. A powerful suspicion was gripping him.
He was right!
One of the great prehistoric beavers lay dead! The rear legs were tied together tied with a rope!
"
Kar is responsible for this!" he clipped at the others.
"How could "
"He has visited this crater before. He knows how the weird animals here react. He knew it was a trait with these big beavers to avenge the death of one of their number. So he had his men kill one and drag it here. The animals followed the trail. They can scent us up the trees. They think were the killers."
At this point, the fragment of Docs shirt burned out.
To his ears came a gru-u-ump, gru-u-mpchorus. Lusty teeth working upon their tree retreats! And from the sound, they wouldnt take long to bring down the giant ferns! They seemed to bite in like axes.
"Thank Heaven!" came Oliver Wording Bittmans sudden gasp. "My tree is close enough to other growth that I can crawl to safety! Is there anything I can do to help you men? Perhaps I can decoy them away?"
"Not a chance!" Monk snorted. "There must be a hundred of them! And theyre chewing so fast they couldnt hear anything! Say! My tree is already beginning to sway!"
Doc Savage drew his gun.
He fired it downward. A single report! It sounded terrific.
An astounding thing promptly happened!
The entire colony of prehistoric beavers quit gnawing. They stampeded! Away through the jungle they went at top speed! Not an animal remained behind!
"Bless me!" Monk chuckled. "What kinda magic you got in that smoke-pole, Doc?"
Doc Savage was actually as surprised as the others. Then the explanation came to him. How simple!
"What is the method the beaver uses to warn its fellows of danger?" he asked.
"It hauls off and gives the water a crack with its tail," Monk replied.
"That explains it," declared Doc. "These giant prehistoric beavers use the same danger warning, evidently. They mistook the sound of the shot for an alarm given by one of their number."
Monk burst into loud laughter.
Chapter 20. THE DEATH SCENE
THE remainder of the night was uneventful if noisy.
With daylight, and the simultaneous retiring of the more ferocious of the colossal reptiles, Doc and his men slid down their tree ferns to see what damage the overgrown beavers had done.
Docs shot had not been fired any too soon. Monks tree was supported by a piece no thicker than his wrist. And some of the others were as near falling.
One noteworthy incident enlivened their investigations.
"Its gone!" Oliver Wording Bittmans shriek crashed out.
The skeleton-thin taxidermist was clutching madly at his watch chain.
"My skinning scalpel!" he wailed. "It has disappeared! I had it when I retired, I am certain!"
Doc helped Bittman look for the scalpel under the tree. They didnt find it. Bittman seemed distraught.
"It can be replaced for a few dollars," Doc suggested.
"No! No!" Bittman muttered. "It was a keepsake. A souvenir! I would not have taken five hundred dollars for it!"
Unable to locate Bittmans vanished trinket, the adventurers set out in search of breakfast. They cannily kept close to the giant tree ferns which offered the best safety available to man here in the ghastly lost domain of time.
Doc Savage it was who bagged their breakfast. A large ground sloth flushed up in their path. A bronze flash, Docs mighty form overhauled it. A rap of his mighty fist stunned the creature. It resembled a cross between a tailless opossum and a small bear, and looked inviting enough.
"It feeds on herbs and such fruit as there is," Doc decided. "It shouldnt be bad eating!"
It wasnt. But before eating, while the sloth was cooking over a fire near a steaming brook, Doc took his exercises. He never neglected these. The previous morning he had taken them in the tree, although he had not slept a wink during the night.
The kit containing the vials of differing scents and the mechanism which made the high and low frequency sound waves had reposed in his pocket throughout. It was, other than their arms, practically the only piece of their equipment they had saved.
After breakfast, Doc made an announcement.
"Im leaving you fellows. Stick together while Im gone. I mean that! Dont one of you get out of sight of all the others! The danger always afoot in this place is incalculable!"
"Where you going, Doc?" Ham queried.
But Doc only made a thin bronze smile. A swift motion and he was gone! The earth might have swallowed him.
Docs friends would have been awe-stricken had they seen the pace with which he traveled now. His going was like the wind. For there was no need to accommodate his steps to the limited speed of his less acrobatic companions. He seemed but to touch the rankest wall of jungle and he was through. Often he took to the top of the growth, leaping from bush to creeper to bush, maintaining balance like an expert tightrope walker.
Near the slain prehistoric beaver which had been dragged to their nocturnal refuge by Kars men, Doc picked up a trail. Kars men had numbered two!
Docs speed increased. He swept along the trail like a bronze cloud pushed by a swift, if a bit sporadic, breeze. A mile dropped behind him, then another.
His golden eyes missed little of the amazing prehistoric life about him.
One incident intrigued him particularly.
He glimpsed a very black, sleek animal. It had white stripes and spots traveling the length of its body. In size, it approximated an African lion. But it was vastly different in build, being chunky and sleepy looking.