vessel down here under the sea?" asked Jack.

"By the gyrocompass," answered Bill Witt, pointing to where Executive Officer Binns and Commander McClure stood in the conning tower. "We are running blind down here, except that the skipper knows from his compass which direction we are going, and he has charts that tell him the depth of the sea at this point. They know the longitude and latitude and can easily determine on their maps and charts just where we are."

"How deep down can we go?" inquired Ted.

"Most of the boats have to be tested at a depth of two hundred feet before they are accepted by the government from the builders," replied Bill. "But you can bet your life we don't often go down that far. When we do, the water is oozing through the thin steel hull and dropping in globules from the sides and top of the vessel. From sixty to a hundred feet is our average plunge."

Even at that moment the boys noticed that the Dewey was "sweating" a little bit, the vaulted steel above them, coated with a composition that contained cork, being dotted here and there with drops of water. Jack craned his neck to look at the depth dial and noted the indicator hand was pointing at seventy-two feet.

Mess was served at noon while the Dewey kept on her run. Coffee and biscuits made up the frugal meal this time, the officers and crew being anxious to prove the submersible ready for any emergency call that Uncle Sam might make, and not desiring to spare the men from their posts longer than possible.

All afternoon the Dewey ploughed the waves, sometimes running submerged, other times on the surface. About five o'clock the boys perceived the lighthouse at the bay entrance, and soon they were back in the navy yard. Their letters home that night thrilled with accounts of their first dive under the ocean, and in their dreams the boys were sharing all manner of wonderful exploits against the foe on the boundless sea.

For several weeks the Brighton recruits were kept busily at the business of mastering submarine navigation. In the distribution of the crew throughout the vessel Jack and Ted found themselves assigned under the leadership of Chief Gunner Mowrey. In turn the boys were drilled in the forms for loading and firing torpedoes from the chambers in the bow of the boat, and in manning the four-inch guns above deck, as well as the anti-aircraft guns that poked their noses straight up in the air and sent up shells much after the fashion of Fourth of July skyrockets. The crew had pet names for their guns. The forecastle gun was nicknamed "Roosey" for Colonel Roosevelt, the gun aft was dubbed "Big Bob" in honor of "Fighting Bob" Evans of Spanish-American War fame, while the anti-aircraft guns became "the Twins."

"Hope we get a shot at a zepp some day soon with one of the Twins," sighed Jack one afternoon after the gun crew had finished peppering to pieces a number of kites that had been raised as targets.

"Yes, and I hope we get that shot at the zepp before the zepp gets one at us," replied Ted, as he recalled the stories he had read of the submarines being visible while yet under water to aircraft directly overhead, and thus being a ready target for a sky gunner.

Coming in the next afternoon from a run to shake down the engines, the boys on the Dewey found the navy yard in the vicinity of the submarine fleet moorings in a commotion. Motor trucks were depositing piles of goods near the piers which were being lightered to some units of the submarine fleet in motor launches. Officers were hurrying to and fro between their vessels and the shore and there was a general air of suspense that seemed to indicate early action of some kind.

The Dewey was wigwagged to take up a position near the other undersea craft that were being provisioned and fueled, and very soon supplies were coming aboard.

"Looks like we are going away from here," suggested Ted to his sailor comrade.

"It's a guess I've been making myself," answered Jack.

Their surmises were all too true, for very soon Commander McClure, who had been ashore for some hours now while the businesslike preparations were in progress, came alongside in the launch of the commandant of the yard and called his staff of officers into executive conference down in the officers' quarters. The news spread quickly through the Dewey as though by magic, that the submarine was due to get away during the night under sealed orders. A few minutes later Bill Witt confirmed the news. He was on night watch and had heard it from the officer of the deck.

Under sealed orders! Where and what!

CHAPTER IV

SOMEWHERE IN THE NORTH SEA

The Dewey was off! Shortly after midnight the little craft got under way, with her nose pointed out of the harbor.

"I guess it's 'so long U.S.A.' this time," confided Jack to his chum, as they stood together, aft the conning tower.

"Gee, I'm glad we're off!" answered Ted. "I only hope we are going over there with the rest of the boys."

Although they had yet to learn officially their destination, the Brighton boys, together with other members of the crew of the Dewey, took it for granted they now were on their way to Europe to join the great American fleet and battle with the Imperial German Navy for the mastery of the sea. It had been noised about ever since their enlistment that Uncle Sam's submarine fleet was soon to be sent abroad.

"Going to fight the U-boat snakes with made-in-America snakes!" was the way Bill Witt had sized up, the situation one evening when he and the Brighton recruits had been discussing the likelihood of their getting out on the firing line at an early date.

Jovial Bill Witt had proved such a capital good fellow that Jack and Ted had taken a great liking to him. The three boys were great pals by this time and were always together in their leisure moments. Temperamental Jean Cartier, the smiling little Frenchman who had shipped aboard the Dewey as chief commissary steward, very often joined their circle and spun the boys stories of that dear France and his home near Marseilles.

To-night it was different. There was no levity. Every man seemed to sense the situation and stood to his post of duty grimly conscious of the serious business upon which he had embarked. Through the minds of the lads flitted visions of home and campus.

Jack, dreaming of good old Brighton, was stirred out of his reverie by his chum.

"Do you suppose we will go all the way over under our own power, or will we be towed?" Ted was asking.

"Haven't the least doubt but that we'll stand on our own sea legs," replied Jack. "Don't you remember how we read in the papers early in the war of a bunch of submarines put together in the St. Lawrence River going all the way across to Gibraltar and thence through the Mediterranean to the Dardanelles under their own power?"

Ted did remember, now that it had been called to his mind. It had gripped their imagination at the time; it seemed such a wonderful thing, the fact that submarines small enough to be carried on the decks of huge liners had been able to cross the Atlantic alone and unaided. They had been still further amazed by the feats of the German undersea cargo carrier Deutschland that had made the trip to America and back, and the U-53 that suddenly popped into Newport one summer afternoon.

The night dragged along. Now that they were fairly off, Jack and Ted preferred not to sleep, but rather to keep tabs on the maneuvers of the American fleet.