glimmering past the Nomad. It was luminous with phosphorescence. Amidst the greenish, ghastly glare, was plainly perceptible a darker spot. It was a human head.
“Hold on, Joe! I’ll be with you!” shouted Nat, and then, without hesitation, he mounted the bridge rail at the port side and plunged into the mass of spume.
Fortunately for those interested in the adventures of the Motor Rangers, at that instant a freak of the current spun Joe’s body about and flung him, like a bit of driftwood, toward the side of the Nomad. In a flash Nat’s strong arm was about him. It was just in time, too, for Joe, who had been swept from the bridge unseen when the Nomad encountered the angry maze of cross currents and tide rips, was almost exhausted.
In this condition he was not in full possession of his ordinary presence of mind. He clung to Nat desperately, with a grip that threatened to pull both rescuer and rescued under water together.
Nat, battling with the sharp, angry waves, as choppy and angular as giant fangs, had all he could do without struggling with Joe. Again and again he tried to break the other’s grip, but without avail. The hold of a drowning man or boy is the most tenacious known. It is almost impossible to loosen it.
“Joe, you must let go of me!” gasped out Nat.
But Joe only clung in a more leech-like fashion. What with the other lad’s dead weight clinging to him, and the conditions against which he was laboring, Nat, strong as he was, felt his strength being rapidly sapped.
Luckily, so intense had been the heat, the lads wore only light tropical trousers and sleeveless undershirts. Had they been incumbered with ordinary clothes, they could not have survived a quarter of the time that Nat and Joe did.
Nat began hauling in on his line, but with Joe gripping him so tightly, it was too much of a task.
“Joe, I hate to do it,” he said at length, “but I must, old fellow, I must!”
With these words, Nat did what he would have done with anybody else when first he realized the conditions. He struck Joe a blow on the head that completely robbed him of his senses. The lad’s vise-like grip relaxed. Under these circumstances, Nat could handle him easily.
By strong, rapid, over-hand motions, he hauled himself and his burden closer and closer to the side of the Nomad. At last they reached it. And now came the most difficult part of Nat’s enterprise. He had to get back on board, and, more than that, to get Joe there, too.
The Nomad was rolling and plunging till she was almost rail under at every roll. A sudden lurch of extra violence gave Nat his opportunity. It brought the bridge rail within reach of his free hand. He grasped it with a tenacious grip. But the next instant he was almost flung back into the sea again, as the little craft righted, and the lad, with his unconscious burden, was carried high above the boiling waters.
But Nat’s muscles had been trained to nickel steel suppleness and strength. He managed to hold on somehow, and the next roll to port of the Nomad gave him an opportunity to get one foot on the edge of the bridge. Thus he clung till the next wild roll in the opposite direction was over.
Then exerting a reserve force he had never before had occasion to bring into play, the young captain drew up Joe’s limp form and bundled it bodily within the bridge railings. This done, he clambered over himself. But he felt queer and dizzy. He could hardly keep his feet, even though he hung on to the rail. His head spun like a teetotum.
“I – why, what’s the matter with me? I – I believe I’m going to – ”
Nat did not conclude his sentence in words. Instead, he enacted it by giving a crazy plunge backward and collapsing in a heap, almost alongside the unconscious Joe.
CHAPTER III.
THE ISLANDS VANISH
Nat sat upright with a strange singing sound in his ears. It was insufferably hot. He fairly panted as he opened his eyes. The sweat ran off him in rivulets. For an instant recollection paused, and then rushed back in an overwhelming flood.
“We were in that channel between those two queer islands,” mused Nat; “and we – gracious, where are the islands?”
He had staggered dizzily to his feet and was looking about him. He knew he could not have lain senseless very long, for his garments were still wet, despite the intense heat. But the islands were nowhere to be seen.
It was still partially dark, a murky twilight replacing the former deeper blackness. But an indefinable change had taken place, somehow, in the atmosphere. Nat drew in his breath with difficulty. It seemed to scorch his lungs.
He glanced over the side of the craft and then drew back with an alarmed cry. The water all about them was bubbling and eddying furiously. A shower of spray from one of the miniature waterspouts struck Nat in the face. It was this that caused his exclamation and made him step back hastily, just as if, in fact, he had been struck a blow in the face.
The water was boiling hot!
Where it had spattered on the lad’s skin it had instantly raised blisters.
“Well, we certainly have landed in a surprising sort of fix this time,” muttered Nat to himself.
He bent over Joe. The lad had not yet regained his senses. But he was breathing heavily, and this stilled a dreaded fear, which, for a moment had almost caused Nat’s heart to stop beating.
“This air is suffocating,” gasped Nat presently. “It smells like it does when they are fumigating a room.”
He ran his tongue around his dry mouth in an effort to moisten it, for it felt parched and cracked. The reek of sulphur in the air, too, caused his throat to contract and his nose and eyes to tingle unmercifully.
But this stench also told Nat something. It furnished him with a partial explanation of the extraordinary occurrences that, as it seemed, were not yet over.
“This whole disturbance is volcanic,” reasoned the boy. “That is the cause of this awful sulphur smell. But that doesn’t account altogether for the sudden disappearance of those islands. I wonder – ” But here he broke off his meditations.
Joe was plainly in need of immediate attention, and Nat devoted his efforts to trying to raise the recumbent lad. He wanted to get him below to the cabin, where there was a well-stocked medicine chest and a supply of reasonably cool water.
But, weakened as he was, Nat couldn’t accomplish the task.
“What’s the matter with me, anyhow?” he asked himself half angrily. “This sulphur stuff must have knocked all my senses out of my head. Where’s Ding-dong, I wonder?”
He rang the engine-room call sharply. But there was no response. No Ding-dong appeared.
“Maybe the signal is out of whack,” muttered Nat, who had noticed some time before that the engine had stopped running. “Guess I’ll go below and see what’s the matter.”
It was the work of an instant to reach the hatchway leading below, and dive into the engine room. What met Nat’s eyes there made him jump almost as violently as he had when the boiling water struck him.
“Great Scott!” he exclaimed, as his gaze fell on the unconscious engineer, “if this isn’t worse and more of it. Poor Ding-dong is knocked out, too; cut on the head. It doesn’t seem to be a bad gash, but it
