tered the
water with scarcely a splash.

Then, for the first time, an audible gasp, as that of one person, came
from the lips of the Secret Agents. For now they could see the objective
of the aero-sub. A monster shadow in the water, at a depth of five
hundred feet. A shadow which, as Maniel manipulated his instruments,
became a floating underwater fortress, ten times the size of any
submarine known to the Americas.

Sporting like porpoises about this held-in-suspension fortress were
myriads of other aero-subs, maneuvering by squadrons and flights,
weaving in and out like schools of fish. The plane which had bourne
Prester Kleig churned in between two of the formations, and vanished
into the side of the motionless monster of the deep.

The striking of a deep sea bell, muted by tons and tons of water,
sounded in the Secret Room.

"Don't turn it off, Maniel," said Kleig. "There's more yet!"

And there was, for the sound of the bell was a signal. The aero-subs,
darting outward from the side of the floating fortress like fish darting
out of seaweed, were plunging up toward the surface of the Atlantic.
Breathlessly the Secret Agents watched them.

They broke water like flying fish, and their wings shot backward from
their notches in the myriad bulbous bodies to click into place in flying
position as the scores of aero-subs took the air above the invisible
hiding places of the mother submarine.

* * * * *

At eight thousand feet the aero-subs swung into battle formation and, as
though controlled by word of command, they maneuvered there like one
vast machine of a central control--beautiful as the flight of swallows,
deadly as anything that flew.

The Secret Agents swept the cold sweat from their brows, and sighs of
terror escaped them all.

At that moment came the voice, loud in the Secret Room, which Kleig at
least immediately recognized:

"Well, gentlemen, are you satisfied that resistance is futile?"

And Kleig whispered the name, over and over again.

"Moyen! Moyen!"

It was Prester Kleig, Master of the Secret Room, who was the first to
regain control after the nerve-numbing question which, asked in far
Madagascar, was heard by the Agents in the Secret Room.

"No!" he shouted. "No! No! Moyen, in the end we will beat you!"

Only silence answered, but deep in the heart of Prester Kleig sounded a
burst of sardonic laughter--the laughter of Moyen, half-god of Asia.
Then the v