w?"

"Simply the discarded light of the spectrum. By removing this cover on
the disk, the different colored rays shoot up. That was to attract
attention. I used only white light through the periscope."

"And it was this invisible light that blinded so many men, which in your
hands blinded the crews of the Japanese?" asked the admiral.

"Yes, sir. The ultraviolet rays are beneficial as a germicide, but are
deadly if too strong."

"Lieutenant Metcalf," said the admiral, seriously, "your future in the
service is secure. I apologize for laughing at you; but now that it's
over and you've won, tell us about the spectacles."

"Why, admiral," responded Metcalf, "that was the simplest proposition of
all. The whole apparatus--prisms, periscope, lenses, and the fluorescing
screen--are made of rock crystal, which is permeable to the ultraviolet
light. But common glass, of which spectacles are made, is opaque to it.
That is why near-sighted men escaped the blindness."

"Then, unless the Japs are near-sighted, I expect an easy time when I go
out."

But the admiral did not need to go out and fight. Those nine big
battle-ships that Japan had struggled for years to obtain, and the
auxiliary fleet of supply and repair ships to keep them in life and
health away from home, caught on a lee shore in a hurricane against
which the mighty _Delaware_ could not steam to sea, piled up one by one
on the sands below Fort Point; and, each with a white flag replacing the
reversed ensign, surrendered to the transport or collier sent out to
take off the survivors.

IN THE VALLEY OF THE SHADOW

There are few facilities for cooking aboard submarine torpedo-boats, and
that is why Lieutenant Ross ran his little submarine up alongside the
flag-ship at noon, and made fast to the boat-boom--the horizontal spar
extending from warships, to which the boats ride when in the water. And,
as familiarity breeds contempt, after the first, tentative, trial, he
had been content to let her hang by one of the small, fixed painters
depending from the boom; for his boat was small, and the tide weak,
bringing little strain on painter or boom. Besides, this plan was good,
for it kept the submarine from bumping the side of the ship--and paint
below the water-line is as valuable to a warship as paint above.

Thus moored, the little craft, with only her deck and conning-tower
showing, rode lightly at the end of her tether, while Ross and his
men--all but one,