native State, and they had forthwith invested enough money in it to enable the young inventor to build a full-fledged machine, and to go to see the Secretary about its employment in the impending conflict. Harry Borden was a good talker, but he could not talk the government of the United States into prompt action.

"My dear young friend," said the Secretary, "I am sure that your invention will prove of inestimable value to the United States in time of war."

"It's the time of war now, isn't it?" said Harry.

"Yes, yes, to be sure; but this is a matter which must be laid before Congress, and a bill must be introduced regarding it. I should advise you to see the Congressman from your district about that. I will give you a letter to him saving that I heartily approve of your machine."

"But, sir, while all this is going on we are losing valuable time. My machine ought to be down there damaging the enemy."

"Really, my dear young friend, you must allow things to take their course."

"Why can't you give me permission to go ahead on my own hook?"

"Embark in private warfare? Privateering is out of date, my young friend. But, ah—um—I may say that—ah—if you should go down there and succeed in inflicting serious damage on the British fleet, I think—mind, I say only that I think—the government would ignore the irregularity of the proceeding."

"That's enough for me," said Harry, springing to his feet. "If my backers will consent, I'll be there in less than a week; and, mark my word, sir, you'll hear of my machine down there, sir."

And before the astonished Secretary could say more, Harry Borden had bounded from the room.

The British cruiser Ajax III. was steaming at a speed of ten knots through the blue waters of the Caribbean Sea. She had been carrying certain despatches of grave importance from Vice-Admiral Sir Wallace Bruce to the Governor of Jamaica, and was now returning in a leisurely manner, which told of economy in the coal department. The Ajax III. was an armored cruiser of about 6000 tons. She carried armor eight inches thick on her sides, and had a steel protective deck four inches thick. Her main battery consisted of four improved Smith-Dodge-Hopkins 8-inch rapid-firing breech-loaders, capable of discharging four of the new steel-iridium conical projectiles every minute, with a point-blank range of two miles, and an initial velocity of 3000 feet per second. Her secondary battery consisted of six 4-inch revolving guns, discharging seventy shells a minute when operated by electricity. The cruiser had the new compound quintuple engines, capable of driving her twenty-six knots an hour under forced draught. On the whole, she was regarded as a fairly efficient vessel, though some of the leading British critics declared that she belonged to a type that was fast becoming obsolete.

She was moving gently and steadily through the water. The sun was shining brightly, and his gleaming rays made sparkling light along the cruiser's polished brass-work and on the brown chases of her long slender guns. Captain Dudley Fawkes was pacing the after-bridge in conversation with his Executive Officer, Commander Bilton-Brooks, and Lieutenant Sir Edward Avon was the officer of the watch on the main bridge.

"I don't believe," said Captain Fawkes, "that the United States means seriously to take a hand in this light."

"I don't know about that," responded Commander Bilton-Brooks. "Congress has taken action, and the President has called out troops."

"True enough," rejoined the Captain, "but that does not necessarily mean anything. You know the navy must be the aggressive force, and we have yet to see an American ship afloat in these waters."

"That is quite true," said the Executive Officer; "yet, for the life of me, I can't help feeling that there is mischief of some sort in the air."

The Executive Officer's words were more nearly correct than even he suspected, for at that very instant the two lookouts in the foretop were puzzling their eyes and brains to make out a strange object which had appeared on the lee beam. While they were watching it, it dropped from the air, where it had seemed to be floating, and rested on the bosom of the sea, where it presently resolved itself into a cutter-yacht some sixty feet in length.

"It were a bloomin' mirage, Bill," said one lookout to the other, as he lifted his voice and bawled, "Sail, ho!"

"Where away?" came the quick demand from the bridge.

"On our lee beam, sir," answered the man. "Looks like a cutter-yacht, sir."

Now in the year 1927 a cutter-yacht was something of a curiosity, for electricity had supplanted sail-power for small craft, and vessels propelled by canvas were rare indeed. The cutter-yacht seen from the decks of the Ajax III. was on the port tack, close hauled and heading so as to intercept the cruiser's course, provided she had speed enough, which was wholly unlikely. She was under full canvas, and though the breeze was very light, she slipped through the smooth water at an amazing speed. This fact dawned on the minds of the Captain and his Executive Officer at the same time.

"She must have an auxiliary electric screw," said Commander Bilton-Brooks.

"I fancy so," said the Captain. "Owned by some fellow who likes to think he's sailing, but has no patience with light breezes. It's rather curious, though, that he should be cruising in these waters at a time like this, isn't it?"

"It certainly is," answered the Executive Officer. "I don't see any flag—do you, sir?"

"No. I rather fancy I shall have to overhaul this yacht, and make her skipper give an account of her. There's a mysterious air about her that I don't half like."

But it was a good deal easier to talk about overhauling the cutter than it was to do it. The yacht's sails, which were made of some extremely light material, like Chinese silk in appearance, were drawing powerfully, and her electric motor—if it really was electric—was doing astounding work. The yacht flashed through the water like some great fish, and so fine were her lines that she left hardly a bubble in her wake. The Captain of the Ajax III. gave orders to increase the speed of the cruiser, and presently the quick throbbing of her engines and the vibrations of her hull told that she was tearing across the long swells at a 25-knot speed. But still the cutter-yacht flew along, and it was evident that she would pass across the cruiser's bow if both held their courses.

"We must stop her lively skipping," said Captain Dudley Fawkes, and he gave orders to sound the call to quarters. The bugle rang out, and the hearty British tars jumped to their stations.

"Cast loose and provide!" ordered Commander Bilton-Brooks.

The ammunition hoists slipped noiselessly upward bearing the steel-iridium shells for the 8-inch guns, and the electric chains hauled up the 70-pounders for the secondary battery. In forty-five seconds the ship was ready to fight, and the order was given to train all forward guns on the cutter and stand by for orders. Then the Captain and his Executive Officer turned their glasses once more on the cutter.

"What on earth is she up to now?" exclaimed the Captain.

"Taking in sail—and spars, too!" cried Commander Bilton-Brooks.

It was true. Not only had the strange cutter let all her thin sails run down, but she seemed to have folded up her mast, boom, gaff, and bowsprit in some strange way and stowed them out of sight.

"Has she shown any flag yet?" asked the Captain.

"None that I have seen," answered the Executive Officer.

"Then I'll wager a month's pay that she's some Yankee invention," declared Captain Dudley Fawkes.

"What in the world are they doing now?" said the Executive Officer.

A strange misshapen mass was rising above the bulwarks of the cutter with surprising swiftness.

"It's a balloon!" exclaimed the