proceed up the Sound," Dirk ordered the officer, "and take
us directly under the craft of the Lodorians."

In a few minutes they were skimming over the surface of the water and,
when a sufficient depth had been gained, the tiny boat disappeared
beneath the rain-rippled sea.

Dirk sat at a port and watched the aquatic life as it was illuminated by
the powerful aquamarine searchlights.

Progress under the water was comparatively slow, as mankind had made but
little progress in underwater navigation. Air liners long before had
almost superseded travel by land and sea and the abolition of warfare
had swept all of the old navies from the ocean.

It was more than an hour before the officer in charge of the boat
announced that the mammoth hull of the monster that was lying on the
Sound was visible directly above them.

Both Dirk and Steinholt donned diving apparatus, and the former
carefully adjusted the mechanism that was contained in a metallic box
about two feet square.

* * * * *

Then they stepped up into a chamber in the conning tower of the boat
and, after a door slipped shut beneath them, water slowly commenced to
pour into the compartment.

When it was full a sliding door that was in front of them slowly opened
and they passed out onto the deck of the underwater craft.

Steinholt had been provided with some welding apparatus and, in a few
minutes, the box which Dirk had carried was attached securely to the
bottom of the craft of the Lodorians.

They then reentered the submarine by reversing the process which had
attended their exit. Very soon they were in the cabin of the boat
again.

"If everything goes well," said Dirk, "those damned Lodorians will never
know what struck them."

"I only hope," said Steinholt, "that we don't destroy that leviathan
altogether. We might solve the secret of it and then we, too, could ride
out into the heart of the universe."

"It is impossible to imagine what will happen," Dirk replied, "until
after we launch our attack."

Both of the men were silent during the return trip of the small undersea
craft, which emerged at its dock a little before three-thirty in the
morning.

"We'll have to hurry," urged Dirk nervously, "because we will need a
little time to make preparations after we get back to Fragoni's."

They entered their plane and Dirk shot it swiftly up into the night,
following the red shaft of light that rose almost directly from