CHAPTER IV On the Golden Trail

IMAGINE the surprise of the boys the next morning when they appeared at the Emerson wharf to report to Captain Austin to find a trim little submarine craft hugging the quay, her hatches open forward and aft to admit her crew, the exhaust of her gasoline engines fluttering from the rear.

"Must be some mistake here; I never knew they explored the bottom of the sea from a submarine," exclaimed Dick in some surprise.

The boys had expected to find some craft of an altogether different nature. The submarine was a new one on them.

"It's the Nemo, all right," said Jay, pointing out the name of the vessel on the prow.

Captain Austin was standing near the conning tower directing various members of the crew as they prepared to cast off and head out of the harbor.

"Good morning, boys, come right aboard," he called out, noting the arrival of the new members of his crew.

Jay and Dick were soon on deck chatting with their captain, noting that Larry Seymour had already arrived. The three boys were assigned to the diving work exclusively and so had nothing to do with the navigation of the craft. In turn Captain Austin introduced the new arrivals to other divers aboard.

"This is Mr. Weddigen—Carl Weddigen—also a new man," said the captain as a huge hulk of a fellow lurched forward when his turn came.

Jay was almost too dumbfounded to speak. The fellow facing him was none other than the big bully he had knocked down the previous afternoon in the corridor of Superintendent Brown's office.

Weddigen backed away, refusing to extend his hand.

Jay smiled. "I guess we have met before," he remarked dryly.

Dick and Larry were on the point of bursting into a hearty guffaw, but restrained themselves.

"What's the idea?" asked the amazed ship captain, noting how Weddigen was reddening.

"I guess Mr. Weddigen can speak for himself," was Jay's only answer, not wishing to create a scene right at the outset of the new adventure.

"Well, that's rather extraordinary," began the captain.

"Just a little unpleasantness that we had yesterday," added Jay, "But we'll forget it now for the good of the cause."

"I hope things will be all right, for he is a very fine diver, according to my information, and can stand a lot with his big physique, so I am told," explained the captain.

"The matter's a closed incident so far as I am concerned," offered Jay. And so the incident was closed, except for knowing glances exchanged among the newest additions to the ship's personnel.

Soon the Nemo had backed away from her moorings and was headed out into Long Island Sound, the most of the divers and those members of the crew not actually engaged in the ship's navigation standing out on deck in enjoyment of the balmy spring morning.

"I guess you would not be averse to knowing something about this craft," began Captain Austin after a half hour's run. He had strolled forward to where Jay, Dick and Larry were watching the backwash of the water as the steel prow of the Nemo sliced its way forward with knife-like precision.

Indeed they would! The three veterans of the war, two of whom had quite a fund of submarine knowledge from their own experiences abroad, were wondering what the Nemo was like. Was it possible that the submersible was a diving bell from which divers could make their exit while it lay on the ocean bed? Were trap doors opened and the pressure of sea water held in abeyance by dense volumes of compressed air? Or did divers go down from the deck of the submarine just as from any other craft? If so, why the submarine, with its narrow, cramped quarters, in preference to any other type of vessel?

These were some of the questions flitting through their minds as they embarked on their first treasure-hunting voyage.

The whole thing was soon to be unfolded by Captain Austin.

"With this craft we do most of our locating," he began. "By that I mean that we are here equipped with special apparatus for finding the lost ships. Many a salvaging company has found that it is one thing to explore a sunken ship or even raise it, but quite another thing to actually locate the submerged ship. It is one thing to know the approximate position where a ship has been sunk, but another thing to know the exact spot. Some charts may give you the exact spot where a ship has foundered, but this spot may measure five miles or more, and if the ship is located in any channel or such parts of the ocean where there is an undertow or heavy undercurrents, the ship will soon be covered with sand, moss or barnacles, and hard for divers to locate."

Plainly, this new salvage company must have some new method of finding ships all their own. The boys were keenly interested and awaiting eagerly the explanation.

"There are several ways to locate lost ships," resumed Captain Austin. "Divers can be sent down with powerful flashlights, but this is a lengthy procedure, and very often takes weeks of patient search. Then again, grappling irons or anchors may be dragged from the salvage ship. This is even less satisfactory than sending down divers. But the Bridgeford Company has a new scheme all its own. And now you shall see."

The Nemo's captain climbed into the turret and motioned the boys to follow him below deck. Dropping straight down into the heart of the ship the boys followed the captain into a small compartment that he was pleased to style "the listening post."

"In here we listen for lost ships just as you listen for the voice of a friend over the telephone. How does that strike you?"

While in the Navy Jay and Dick had come to know only too well how the microphone was used to hear other vessels, and how it had been a powerful means in the overthrow of the U-boats and the safeguarding of American troops bound for Europe. The microphone listened for moving vessels and was acquainted with their movements because the swish of the propeller blades was borne into the listening device of the Yankee craft.

But how could a salvage ship "listen" for a helpless wreck lying foundered on the bottom of the sea? They were soon to know. Captain Austin conducted them first into the forward hold and showed them another compartment with a massive winch used to raise or lower an object in the water under the keel. Taking them aft he showed another compartment equipped as was the one forward.

"We use the so-called Hughes balance," explained the skipper as the boys gathered close to him in order to hear above the whirr of the throbbing engines. "They are two massive rings suspended by cables and raised or lowered at will by the winches. These rings or cups are wound with copper wire. The lower windings connect with an ordinary telephone receiver while other spools are in series with a microphone and three dry cells. This makes a sensitive instrument."

Dick, who was somewhat of a mechanic, was beginning to see light.

"When these induction coils are trailed through the water from underneath the Nemo the telephone receiver in the control station gives no sound as long as the two balances move through the water," continued the captain. "But the minute one of them comes within the vicinity of a wreck, the electrical balance will be disturbed and the telephone will sound its warning to the operator. The nearer the balances come to the wreck the louder the sound. All you have to do is cruise back and forth near the spot where the sunken vessel is supposed to lie, and sooner or later the faithful induction balance will find the wreck."

"How do you judge for the depth?" asked Dick.

"The depth of the ocean naturally varies more or less," the captain explained further. "If a deeper strata is encountered the induction balances must be lowered further in the water than in cruising in shallow water. Not only will the induction balance give the exact spot where the ship is located, but it will give the precise location even though the lost ship is covered with sand or silt."

"But how do you determine the depth? Do you drop a plumb line, or have you a new method of depth sounding?" persisted Dick, who was taking an engineering course at Brighton preparatory to studying electrical engineering at college. Naturally he was interested in every engineering problem.

Captain Austin smiled whimsically.

"That is another of our new processes," he added after a moment's reflection. "Echo—that's the answer in a nutshell."

The captain led the way to the ship's marimeter, a cylindrical contrivance that looked as though it might house a compass or a binnacle lamp.

"The marimeter works on the principle of electricity controlled by sound vibration," the captain expounded in his competent fashion. "A sound wave is sent out from the bottom of the vessel by mechanical means and the instant this sound is started it is picked up electrically and relayed to the recording instrument and the dial of the latter begins to register. The sound wave travels to the bottom of the ocean and returns in the form of an echo, and this echo is also picked up by the diaphragm in the bottom of the boat and is also relayed by electricity to the recording instrument, causing the pointer to stop immediately. Sound travels at practically a uniform rate in the water, at about 4000 feet a second. The depth is measured by accurately taking and recording mechanically the time for sound to travel down and back. The depth is shown on the dial in fathoms, and four soundings may be made per minute."

It all sounded so simple, and yet what a wonderful contrivance as against the old-fashioned method of taking deep-sea soundings. To demonstrate Captain Austin took an electrical sounding for his new protegées and in a few seconds the "echo" had returned from the bottom of the Sound, showing a depth of ten fathoms.

For some hours, under the guidance of the ship's skipper, the trio of newcomers thoroughly inspected the Nemo. This plainly was the "prospecting" boat of the salvage company's fleet. It went out and staked the claim and then called on the full facilities of the fleet for completion of the job.

Captain Austin, completely won by the honesty and candor of his new friends, and acting under instructions of superintendent Brown, took the boys entirely into his confidence.

"I do not mind telling you that we are after high stakes this trip," he told them. "An English steamship, the Dominion, was sunk off Martha's Vineyard late in 1916. She had among her cargo a quantity of gold bullion and South African diamonds. She took fire after being shelled by a German submarine and was making a run for the coast when she went down. She is between two and three hundred feet down and it is our job to look her over for the next few days and report back to Bridgeford on our findings."

The news of impending action was joyously received by Jay and Dick, who declared they were ready on a moment's notice to take their first dip into the blue for their new employers. What! thirty dollars a day, and the chance to win a percentage on any treasure actually reclaimed! It was a wonderful opportunity, to their minds.

"Better take a look over your diving equipment and see that everything is all right," suggested the ship's captain. Jay and Dick accordingly went thoroughly over their outfits during the next few hours, finding suits, shoes, helmets and air-line connections quite up to the standard of the latest improved diving equipment.

It was a lively crew that spent the warm spring evening above decks on the Nemo as she worked her way steadily on her course toward Martha's Vineyard, off the New England coast. By morning they would have arrived at their destination—ready for the adventure!

A sense of eager expectancy pervaded the snug little "sub." Although Captain Austin had not shared his confidences broadcast as he had with his new divers the men seemed to divine that they were out for real business this time. They were for the most part singing merrily and glad to be in on the big game of treasure hunting.

"Tomorrow morning we'll be back at the old stunt again," mused Dick. "Rocked in the cradle of the deep."

"Hope we get the first peep at the poor old Dominion," said Jay. Although this was a dangerous calling the two navy veterans had come to look upon it by now as any other ordinary duty.

"Only thing I don't like about this outfit is that fellow Weddigen," reflected Jay.

"You mean the fellow you punched on the jaw?" Jay nodded.

"Well, just let him start something and we'll show him where he's at," snapped Larry Seymour, who had just strolled up.

"Yes, I reckon we can take care of that gent if he is inclined to get frisky," remarked Dick meaningly, convinced in his own mind that Weddigen was some kind of a tough customer who was playing his own little game in this adventure.