Out in the sunlight, there was an explosion. A man screamed. There were other blasts. They sounded about like shotguns, perhaps a trifle louder. Mixed in with the reports was a shriek started by one man and ended by another.

Monk joined Doc Savage. Behind him, big-fisted Renny Renwick was rubbing his wrists and saying, "Holy cows!" and other things in a tone that was like cannonading in distance.

Monk listened to another explosion. "Nice," he said.

He looked into the container at the puffed-breakfast-foodlike substance which remained.

"Workin' swell, ain't it?" he added.

Johnny came up. He carried the big knife, looked bloodthirsty. "I'll be superamalgamated!" he said.

"What's making the firecracker noises?"

Monk said, "An explosive I invented. In little pellets. Goes off when you step on 'em."

Johnny peered into the container. "This stuff? It looks like puffed wheat."

"See the damp pads?" Monk exhibited the pads in the container. "They're wet, but not with water. With chemicals. As long as the pellets are damp with certain chemical fumes, they won't explode. But the second they dry off, and it don't take over a couple of seconds, either, they're as touchy as rotten eggs."

There were more explosions, more shrieks. Men came rushing back in retreat. Other blasts stopped them. "You mean they're stepping on that stuff and it's exploding?" Renny demanded.

Monk said, "If they ain't, my ears are deceiving me."

The homely chemist went down the corridor cautiously, watching the floor, and making sure that no onegot a chance to take a shot at him.

"Bring that poison gas over here!" Monk roared. "There's a draft in this hall. It will carry the gas right to them." He turned and winked, added, "Be sure you get the poison gas. The heck with that other stuff."

Monk had never held any great regard for the truth.

He listened to distressed squallings from down the corridor.

He winked again.

"They want to surrender," he said.

DOC SAVAGE had an elaborate organization for the career which he followed, and one of the least-known parts of it was the unusual "college" which he maintained in a wilderness section of upstate New York. At this college he maintained a staff of men trained by himself, and to the place he sent such criminals as he caught. A course in the college was unusual-the enrollee first received, whether willing or not, an intricate brain operation which wiped out all memory of the past. Following this, the student was taught a trade, and taught to hate crime. Graduates knew nothing of their past, were good citizens, equipped for making a living in an increasingly technical civilization.

Because the existence of the "college" was completely secret, Doc Savage had some difficulty explaining to Peter and Lada Harland what was happening to the prisoners-Chet Farmer, Bodine, Cy and the others-without revealing the truth.

The prisoners were being ferried ash.o.r.e, placed in ambulances, and the Harlands were curious.

Peter Harland saw that the bronze man was reluctant.

"My guess is that whatever you are doing is probably good for them," he said. "I'm not going to ask any more questions."

Doc changed the subject. He asked, "How did you come out with Monk? Get his natural color back?"

"Fairly well," Harland said. "Eyes and hair and teeth are not natural, exactly. However, we did do very well with the teeth. We discovered that an ordinary lead shield will stop the coloring effect, so that we were able to make his teeth white."

Doc said, "I am anxious to go over that device. It opens a new field for scientific research."

Peter Harland looked uncomfortable. "That very point was on my mind."

"How do you mean?"

Harland rubbed his forehead slowly. "To be frank, I do not think-well, I wish I had never found that d.a.m.ned thing." He became animated, concerned. "Do you realize what it means? It will wipe out whole industries-the dye industry, for instance. And those diamonds-I hate to think of what will happen to the diamond market if you can start making commercial black diamonds into white or blue-white stones that are worth hundreds of dollars a carat."

"What would you suggest?"

Harland hesitated. "The thing might undergo more experimentation. And eventually be introducedgradually, so as not to affect employment."

"It might."

"Would . . . would you be interested in taking control of the thing, to prevent something like this thing we've just gone through?"

Doc Savage nodded. "We might work that out," he agreed.

Monk was trying to work out something, too, but along different lines. Along the lines of Lada Harland.

She had very good lines, too. Her brother had done his best with the color-change gadget, and the result was a delightful honey blonde. Ravishing was the word.

The fly in the ointment was Ham. Ham seemed to have the same ideas as Monk.

Concerning Monk, Ham said, "That homely missing link! That accident of nature, His feet are so big"-Ham groped for a suitable comparison-"that it looks as if half his legs were bent under."

Monk overheard that. He said, "One of these days I'm gonna dance on your grave."

"That's great," Ham said. "I'll see if they won't bury me at sea."

THE END.