In another second the

waters of Omean closed above my head, and the three of us were

making for the little flier a hundred yards away.

Xodar was burdened with the boy, and I with the three long-swords.

The revolver I had dropped, so that while we were both strong

swimmers it seemed to me that we moved at a snail's pace through

the water. I was swimming entirely beneath the surface, but Xodar

was compelled to rise often to let the youth breathe, so it was a

wonder that we were not discovered long before we were.

In fact we reached the boat's side and were all aboard before the

watch upon the battleship, aroused by the shots, detected us. Then

an alarm gun bellowed from a ship's bow, its deep boom reverberating

in deafening tones beneath the rocky dome of Omean.

Instantly the sleeping thousands were awake. The decks of a thousand

monster craft teemed with fighting-men, for an alarm on Omean was

a thing of rare occurrence.

We cast away before the sound of the first gun had died, and

another second saw us rising swiftly from the surface of the sea.

I lay at full length along the deck with the levers and buttons

of control before me. Xodar and the boy were stretched directly

behind me, prone also that we might offer as little resistance to

the air as possible.

"Rise high," whispered Xodar. "They dare not fire their heavy

guns toward the dome--the fragments of the shells would drop back

among their own craft. If we are high enough our keel plates will

protect us from rifle fire."

I did as he bade. Below us we could see the men leaping into the

water by hundreds, and striking out for the small cruisers and

one-man fliers that lay moored about the big ships. The larger

craft were getting under way, following us rapidly, but not rising

from the water.

"A little to your right," cried Xodar, for there are no points of

compass upon Omean where every direction is due north.

The pandemonium that had broken out below us was deafening. Rifles

cracked, officers shouted orders, men yelled directions to one

another from the water and from the decks of myriad boats, while

through all ran the purr of countless propellers cutting water and

air.

I had not dared pull my speed lever to the highest for fear of

overrunning the mouth of the shaft that passed from Omean's dome

to the world above, but even so we were hitting a clip that I doubt

has ever been equalled on the windless sea.

The smaller fliers were commencing to rise toward us when Xodar

shouted: "The shaft! The shaft! Dead ahead," and I saw the opening,

black and yawning in the glowing dome of this underworld.

A ten-man cruiser was rising directly in front to cut off our

escape. It was the only vessel that stood in our way, but at the

rate that it was traveling it would come between us and the shaft

in plenty of time to thwart our plans.

It was rising at an angle of about forty-five degrees dead ahead of

us, with the evident intention of combing us with grappling hooks

from above as it skimmed low over our deck.

There was but one forlorn hope for us, and I took it. It was useless

to try to pass over her, for that would have allowed her to force

us against the rocky dome above, and we were already too near that

as it was. To have attempted to dive below her would have put us

entirely at her mercy, and precisely where she wanted us. On either

side a hundred other menacing craft were hastening toward us. The

alternative was filled with risk--in fact it was all risk, with

but a slender chance of success.

As we neared the cruiser I rose as though to pass above her, so

that she would do just what she did do, rise at a steeper angle to

force me still higher. Then as we were almost upon her I yelled

to my companions to hold tight, and throwing the little vessel into

her highest speed I deflected her bows at the same instant until

we were running horizontally and at terrific velocity straight for

the cruiser's keel.

Her commander may have seen my intentions then, but it was too late.

Almost at the instant of impact I turned my bows upward, and then

with a shattering jolt we were in collision. What I had hoped for

happened. The cruiser, already tilted at a perilous angle, was

carried completely over backward by the impact of my smaller vessel.

Her crew fell twisting and screaming through the air to the water

far below, while the cruiser, her propellers still madly churning,

dived swiftly headforemost after them to the bottom of the Sea of

Omean.

The collision crushed our steel bows, and notwithstanding every

effort on our part came near to hurling us from the deck. As it

was we landed in a wildly clutching heap at the very extremity of

the flier, where Xodar and I succeeded in grasping the hand-rail,

but the boy would have plunged overboard had I not fortunately

grasped his ankle as he was already partially over.

Unguided, our vessel careened wildly in its mad flight, rising ever

nearer the rocks above. It took but an instant, however, for me

to regain the levers, and with the roof barely fifty feet above I

turned her nose once more into the horizontal plane and headed her

again for the black mouth of the shaft.

The collision had retarded our progress and now a hundred swift

scouts were close upon us. Xodar had told me that ascending the

shaft by virtue of our repulsive rays alone would give our enemies

their best chance to overtake us, since our propellers would be

idle and in rising we would be outclassed by many of our pursuers.

The swifter craft are seldom equipped with large buoyancy tanks,

since the added bulk of them tends to reduce a vessel's speed.

As many boats were now quite close to us it was inevitable that we

would be quickly overhauled in the shaft, and captured or killed

in short order.

To me there always seems a way to gain the opposite side of

an obstacle. If one cannot pass over it, or below it, or around

it, why then there is but a single alternative left, and that is

to pass through it. I could not get around the fact that many of

these other boats could rise faster than ours by the fact of their

greater buoyancy, but I was none the less determined to reach the

outer world far in advance of them or die a death of my own choosing

in event of failure.

"Reverse?" screamed Xodar, behind me. "For the love of your first

ancestor, reverse. We are at the shaft."

"Hold tight!" I screamed in reply. "Grasp the boy and hold tight--we

are going straight up the shaft."

The words were scarce out of my mouth as we swept beneath the

pitch-black opening. I threw the bow hard up, dragged the speed

lever to its last notch, and clutching a stanchion with one hand

and the steering-wheel with the other hung on like grim death and

consigned my soul to its author.

I heard a little exclamation of surprise from Xodar, followed by a

grim laugh. The boy laughed too and said something which I could

not catch for the whistling of the wind of our awful speed.

I looked above my head, hoping to catch the gleam of stars by which

I could direct our course and hold the hurtling thing that bore us

true to the centre of the shaft. To have touched the side at the

speed we were making would doubtless have resulted in instant death

for us all. But not a star showed above--only utter and impenetrable

darkness.

Then I glanced below me, and there I saw a rapidly diminishing

circle of light--the mouth of the opening above the phosphorescent

radiance of Omean.