I could do no good behind this grill. It was the act of a contortionist to turn in that meager space, but somehow I accomplished it, scrambled desperately toward the corridor grill through which I had entered the air-duct.

It was just as I gained the opening that the hinges of the lock finally gave way, the door burst open. Even I was not prepared for that which appeared through the frame. The entire aperture was one solid sheet of flame. Despite their eagerness, no one could blame my men for falling back, horrified, from the scorching fingers that leaped out to grasp them.

All but one! And that one was Dr. Thomas Mallory. Perhaps it was because he alone realized the vital necessity of jerking that fuse from its charge before everything ended in one coruscant moment. Arms locked before his face, head lowered, he dashed recklessly into that flaming hell!

I fell—or dropped, I know not which—from my outlet, found myself on my feet, heard myself bellowing, "Water! We've got to stop that fire before—"

But they knew that. Already someone had raced to the jets, another was tugging desperately at a reel of fire hose. I suppose what I did next was heroic. Either that or damned, blind foolishness. It could not have been deliberate heroism, for there was no time to measure the chances, weigh the consequences. I leaped through the doorway, followed Dr. Mallory. And even so, there was another figure at my side. That of burly Bruce MacGregor.

We found him at the same time. He lay face down on the floor, arms outstretched before him. But in one blistered hand was—the end of the fuse. Scant inches from its charred end stood piled boxes of Triple-X, most deadly of all explosives. The flames had not yet quite reached it, but in another moment—

Then the water came! Like a solid fist it caught me in the middle of the back, shot me, sprawling, forward. The breath shot from my lungs before that impact—but never had I been more grateful for a bruising blow.

MacGregor, a sorry sight with his blistered cheeks, scorched hair, spark-charred garments, bent his brute strength against the flood, roared directions.

"Here! On these boxes first! Soak them, ruin them! We can fight the fire later...."