There was not a soul about, not even a watchman.  Hastily we took in the place, a forge and a number of odds and ends of metal sheets, rods, pipes and angles.

Beside a workbench stood two long cylinders, studded with bolts.

“That’s what I’m looking for,” exclaimed Craig.  “Here, Walter, take one.  I’ll take the other—­and the tubes—­and—­”

He did not pause to finish, but seized up a peculiar shaped instrument, like a huge hook, with a curved neck and sharp beak.  Really it was composed of two metal tubes which ran into a cylinder or mixing chamber above the nozzle, while parallel to them ran another tube with a nozzle of its own.

We ran, for there was no time to lose.  As nearly as I could estimate it, the water must now be slowly closing over Elaine.

“What is it?” I asked as he joined up the tubes from the tanks to the peculiar hook-like apparatus he carried.

“An oxyacetylene blowpipe,” he muttered back feverishly working.  “Used for welding and cutting, too,” he added.

With a light he touched the nozzle.  Instantly a hissing, blinding flame-needle made the steel under it incandescent.  The terrific heat from one nozzle made the steel glow.  The stream of oxygen from the second completely consumed the hot metal.  And the force of the blast carried a fine spray of disintegrated metal before it.  It was a brilliant sight.  But it was more than that.  Through the very steel itself, the flame, thousands of degrees hot, seemed to eat its way in a fine line, as if it were a sharp knife cutting through ordinary cardboard.

With tense muscles Kennedy skillfully guided the terrible instrument that ate cold steel, wielding the torch as deftly as if it had been, as indeed it was, a magic wand of modern science.

He was actually cutting out a huge hole in the still exposed surface of the tank—­all around, except for a few inches, to prevent the heavy piece from falling inward.

As Kennedy carefully bent outward the section of the tank which he had cut, he quickly reached down and lifted Elaine, unconscious, out of the water.

Gently he laid her on the sand.  It was the work of only a moment to cut the cords that bound her hands.

There she lay, pale and still.  Was she dead?

Kennedy worked frantically to revive her.

At last, slowly, the color seemed to return to her pale lips.  Her eyelids fluttered.  Then her great, deep eyes opened.

As she looked up and caught sight of Craig bending anxiously over her, she seemed to comprehend.  For a moment both were silent.  Then Elaine reached up and took his hand.

There was much in the look she gave him—­admiration, confidence,—­ love itself.

Heroics, however, were never part of Kennedy’s frank make-up.  The fact was that her admiration, even though not spoken, plainly embarrassed him.  Yet he forgot that as he looked at her lying there, frail and helpless.