Two days passed uneventfully; then shortly before sunset on the third day the look-out reported a periscope about a thousand yards distant and three points off the port bow. Cappy Ricks' old knees promptly commenced to knock together with excitement.

“Here's where Terence gets that torpedo if he doesn't come up out of the engine room,” Mike Murphy remarked laconically, and promptly whistled Terence on the engine room speaking tube. “Come up or be blown up,” he yelled.

“Divil a fear! We're comin',” Terence replied.

The chief and his crew had just reached the deck when the black shining turtleback of the submarine broke water.

“They have to come to the surface to discharge a torpedo,” Murphy explained to Cappy Ricks.

“Great Godfrey! Here it comes!” shrilled Cappy, and watched, fascinated, the wake of the torpedo as it raced toward them. Just as Terence Reardon and his engine crew came panting up on the bridge, the old Costa Rica walked into it. “Me ingine room! I knew it!” cried Terence. Then the explosion came.

From where he lay on his back, half stunned, Cappy Ricks saw water and wreckage fly high in the air. The Costa Rica shivered. So did Cappy. Then the debris descended, and Cappy, choked with salt water, dimly realized that Terence Reardon had him in his arms and was carrying him down to the boat deck, where the motor lifeboat swung wide in the davits.

“Here, take the boss from me,” Terence commanded, and passed Cappy to a negro fireman, who carried the old man forward and laid him on a pile of blankets, previously placed there for just such an emergency.

Then the lifeboat commenced to drop away from the towering black topside and Cappy was aware of Michael J. Murphy's face—white, anxious, terrified—gazing down at him from the ship's rail.

“I'm just suffering from the shock,” Cappy called. “Mike, you 'tend to business. Remember what I told you and tell the crew to keep their mouths shut. He'll do the natural thing and walk into your hand.”

Murphy, reassured, waved his hand, and with his gun crew fled aft to the little house that protected the auxiliary steering gear from the weather, where they concealed themselves. In the meantime the other lifeboats had been lowered away; the painter from the third boat was passed to the second, which in turn passed its painter to the motor boat, and the ship's company hauled clear of the shattered, sinking ship. The Costa Rica was going down by the head, and Cappy, curious as any human being, sat up to watch his decoy disappear.

The submarine steamed up to them. “What vessel is that?” her commander shouted from the conning tower in excellent English.

“The American steamer Soak-it-to-'em, of Rotten Row,” Cappy Ricks replied, “carrying a cargo of post holes. She has three decks and no bottom.”

“How do you spell the name?” the German bawled.

“Can't hear you,” Cappy fibbed. Then, sotto voce, to Mr. Reardon: “Kick her ahead, Terry.”

“How do you spell the name?” the submarine captain repeated.

Cappy jibbered something unintelligible, and Mr. Reardon added to the puzzle by bellowing the information that the p was silent, as in pneumonia. All this time the motor boat was putting distance between itself and the submarine, and the disgusted German, as a last resort, steamed away and circled round the rapidly lifting stern of the doomed Costa Rica, confident that there he would find the record of her identity and home port—information which, in his methodical German way, he desired to include in his official report to the Admiralty. And while he ratched slowly past, striving to find with his binoculars that which was not, Michael J. Murphy and his bully boys came aft with a rush, tore aside the tarpaulin that screened the stern gun and expeditiously opened fire. To Cappy Ricks' horror Murphy's first shot was a clean miss, and instantly the big sub started to submerge with a hoarse sucking sound that brought despair to Cappy Ricks' heart. She was halfway under before Murphy's gun was reloaded, but quite calmly the gun was traversed and deflected until the black stern flashed across the intersection of the wires in the sight; then Murphy's hand dropped and the gun roared.

“That'll do nicely, lads,” he told his crew. “Tore the stern off her that time; and from this dive she'll not come up. Cappy Ricks was right. He banked on human nature, and if curiosity isn't a human trait then I'm a Chinaman. Overboard with you, and away before the old girl goes under or we'll be sucked down in the vortex.”

And overboard they went, to be picked up five minutes later by Terence and Cappy in the motor lifeboat. “You were right, Mr. Ricks,” cried Murphy as he scrambled into the boat. “Curiosity killed the cat!”

“Yes, and it's blamed near killed me,” Cappy declared feebly. “Some of that debris came down and hit me a slap on the dome—Jerusalem! There goes my decoy—peace to her bones!”

The Costa Rica dove to the Port of Missing Ships. Michael J. Murphy, however, did not turn to see her disappear; he was gazing, instead, at a thin red trickle that came from under Cappy's cap band and was running down his wizened neck. “Mr. Ricks,” he said anxiously, “you're wounded.”

Cappy rubbed the sore spot, and when he withdrew his fingers they were bloody.

“By the Holy Pink-Toed Prophet!” he gasped wonderingly. “You're right, Mike. I've been wounded in action with the enemies of my country! So help me, Mike. I've actually lived to shed my blood for the Stars and Stripes, like any other Ricks.”

He gazed wonderingly at Mike Murphy. “Now I can die happy,” he murmured. “I've done my bit.”

“Yes, begorra,” rumbled Terence P. Reardon, “an' if I have my way about it ye're honorably discharged from the service this minute, Misther Ricks. I'll gallivant no more wit' you in ye're ould breadbaskets av shteamers. 'Tis highly dangerous an' no business for a man of family.”

Mike Murphy grinned at his colleague. “For all that, Terence,” he declared, “you must admit that Mr. Ricks' scheme for destroying submarines is the only practical one yet devised.”

“Thrue for ye, Michael. But shtill, like all fine invintions, the idjea has its dhrawbacks. Now if we could only be sure av a continyous supply av ould ships for use as decoys—”

“I see a smudge of smoke,” cried Gappy Ricks.

Mike Murphy followed the old man's pointing finger. “There's only one kind of boat makes a smudge like that,” he declared; “and it's a destroyer. Safe and well out of a glorious adventure. Faith, we're the lucky devils; and by this and by that, I'll enlist aboard that destroyer, now that I'm here on the job.”

“Do—an' good luck to you!” murmured Terence.

“Amen,” said Cappy Ricks, and fingered his trifling but honorable wound. “Gosh!” he murmured. “If Skinner could only know a thrill like this!”

THE END.