But in spite of the dwarf’s great strength, Nicolas was too big and powerful for him.  The powerfulness the dwarf might have overcome, but the size was too much.

Plucking away the arms that were tightened about his neck, Nicolas held the dwarf away from him with his left hand, then struck him heavily in the face with his right.  Taking a step more toward the center of the cavern, he hurled his opponent across the room.

Nikol struck the floor with a thud and lay still.

Now, realizing the need of haste, Nicolas turned quickly and made as though to move toward the exit.  But he had delayed too long.  The dwarf’s efforts to hold him, though futile, had been enough to prevent the Montenegrin’s escape.

A second huge form—­the form of Ivan—­barred the exit.

“Come on, have a try,” said Ivan, with a grin.

Nicolas gave a loud cry—­the cry of a cornered beast.  Then he sprang.

“I’ll kill you!” he yelled in a voice of thunder.

CHAPTER XI.

A fight.

All the others in the cavern were on their feet now, all save Nikol, who still lay unconscious where Nicolas had hurled him.  Stubbs shrank back in the dark, but Hal, Chester and the two British officers quickly produced revolvers with which they covered Nicolas.

Ivan, out of the tail of his eye, caught sight of these movements.  He let out a roar even as Nicolas sprang upon him.

“Put up those guns!” he shouted.  “I’ll attend to this fellow with my bare hands.  Stand back!”

There was something in the voice of the big Cossack that impelled the others to obey; and they drew back, circling about to watch the struggle.  Even Stubbs picked up courage enough to come forward; and hardly had the fight begun when Nikol, too, pulled himself up and cast his eyes upon the combatants.

Nicolas sprang upon Ivan with outstretched arms, his fingers spread wide.  His object was to clasp one of his strong hands about Ivan’s throat, thus obtaining an advantage at the outset.  But Ivan had divined his intention at the moment he sprang, and ducking with remarkable agility for a man of his size, he came up inside the other’s arms and grasped his opponent around the middle with both arms.

Then he squeezed; and the spectators drew their breaths audibly, for it seemed that no man could stand such a strain.  But Nicolas bore up under it, and when Ivan, out of wind, was forced to relinquish his hold, Nicolas whirled upon him quickly and the fingers of his left hand sank into the Cossack’s throat.  Chester uttered a faint cry of alarm, for a hold such as this, obtained by such a powerful man as Nicolas, was indeed a thing to be feared.  Ivan leaped quickly backward, carrying Nicolas with him, but the latter retained his hold; and then he brought his right fist up under Ivan’s chin.  It was a hard blow and Ivan staggered.