I don't believe the whales will follow us. Or, if they
do, they can't do much damage when we are in motion. It's because we
are stationary and they are moving that the blows seem so violent.
Unless they collide head on with us, in the opposite direction to ours,
we ought to be able to get clear of them. If they persist in following
us--"

He paused as he pulled over the lever that would send the M. N. 1 to
the surface.

"Well, what then?" asked Mr. Damon.

"Then we'll have to use some weapon, and I have several," finished the
young inventor.

A few moments later the craft was in motion, not before, however, she
was struck another blow, but only a glancing one.

"We're puzzling them!" cried Tom.

Having done all that was possible for the time being, Tom hurried to
the observation chamber, followed by the ethers. There Tom switched on
the powerful lights. For a moment nothing was to be seen but the
swirling, green water. Then, suddenly, a great shape came into view of
the glass windows, followed by another.

"Whales!" cried Tom Swift. "And the largest I've ever seen."

It was true. Two immense specimens of the cetacean species were in
front of the submarine, one on either bow, evidently much puzzled over
the glaring lights. They were bow-heads, and immense creatures, and it
would not take many blows from them to disable even a stouter craft
than was the submarine.

But the motion of the undersea ship, the bright lights, and possibly
the feel of her steel skin was evidently not to the liking of the sea
monsters. One, indeed, came so close to the glass that he seemed about
to try to break it, but, to the relief of all, he veered off, evidently
not liking the look of what he saw.

Just once again, before the craft reached the surface, was there
another blow, this time at the stern. But it was a parting tap, and
none others followed.

"They've gone!" exclaimed Mr. Damon, as the whales vanished from the
sight of those in the forward cabin.

"Have you any adequate protection against these monsters of the deep?"
asked Mr. Hardley in a fault-finding voice. "I should think you would
have taken precautions, Swift!"

He had dropped the formal "Mr." and seemed to treat Tom as an inferior.

"We have other protection than running away," said the young inventor
quietly. "There are guns we can use, and, if the whales had been far
enough away, I could have sent a small torpedo at them. Close by it
would be dangerous t