“And so exit Scorpion Agent SC-21!” observed Don Winslow harshly. “He killed himself rather than go down later with the ship. That leaves one enemy agent still unidentified. Who is he, Corba?”

“Seaman Second Class, by the name of Mink,” replied the radioman sullenly. “He’s just a tough gorilla we brought aboard for strong arm work. As it turned out, we didn’t have to use him.”

“Which means you were the bird who shot at us tonight from the corner of the galley!” put in Red Pennington. “You sure hated to let us get a look at those forged enlistment records, didn’t you, Mr. A. Corba?”

With a snort of anger, Captain Riggs turned to the door.

“The whole business smells like plain mutiny to me!” he declared. “While you’re questioning this man, Commander, I’m going to hunt up Seaman Second Class Mink, and throw him in irons! Join me in my quarters, gentlemen, when you’re ready to compare notes.”

X
A DESPERATE SCHEME

The questioning of Anton Corba, Electrician First Class, took less than twenty minutes; but it laid bare the whole Scorpion plot to destroy the gunboat.

Corba and the other two spies had come aboard at Guantanamo. The Navy men whose places they took, had been kidnapped by other Scorpion agents, and held until the gunboat sailed.

“The rest was easy, sir,” the prisoner stated, with a nervous glance at Red Pennington’s gun. “I rigged up a special sending key and an extra short-wave receiver with the help of stuff I’d smuggled aboard. I kept in touch with the Scorpia headquarters by tunin’ into a new wave length they gave me each day. And I listened in to any talk aboard ship with this electric 'ear’ which they say the Scorpion himself invented. Here it is, if you want to look at it.”

Slipping a hand inside his blouse, Corba produced the tiny amplifier and earphone. Don Winslow took it from him, with a smile.