andy was shaky from his experience over on the east side and while bert, harry and blatz went out to a show, he remained at the hotel to rest and think things over.

he was positive that he had seen blatz go into the warehouse and the conviction grew that the german civilian observer was not all that he claimed to be. andy felt a crisis coming, something he couldn’t exactly put into words, but a vague feeling that trouble was just around the corner. he was asleep when the others returned at midnight from the theater and they did not waken him.

andy felt much refreshed the next morning and they decided to accompany harry on his visit to the shipyard.

“it’s the finest tin fish i’ve ever seen,” said bert, who had visited the neptune the afternoon before. “they’ve got just about everything they need in it.”

“it is a wonderful boat,” admitted harry proudly, “but i’ll have to confess that traveling in the neptune won’t be able to compare with the goliath. when we’re submerged the air isn’t any too good if we’re down three or four hours and we’re pretty cramped for space.”

“let’s get under way,” said andy. “i’m anxious to see this wonderful tin fish.”

they took a taxi across town, rolled over the brooklyn bridge and fifteen minutes later were walking into the shipyard where the neptune was being groomed for its polar trip.

the submarine was lying beside a stubby wharf with its main hatch open. workmen were busy passing supplies down into its depths as andy and his party arrived.

“my gosh,” exclaimed andy. “i didn’t suppose you had a submarine of this type. it’s almost as big as one of the navy’s super-cruisers.”

“just about,” agreed harry. “as a matter-of-fact, this sub was built for naval purposes by the seabright yards. they used it as a demonstrator in selling similar models to south american navies. it has just about every modern gadget on it that inventors could devise. as a result of this working model, the seabright people landed contracts for about 25 million in work. the neptune had served its purpose and they were willing to sell it to gilbert mathews at a very reasonable figure when he started looking for a ship in which to make the polar trip. the seabright engineers have made all of the necessary changes for polar cruising and have just put their official approval on the neptune, which means we’ll be starting north within a few days.”

“i’d like to see inside the neptune,” said blatz, adding, “i’ve never been in a submarine before.”

“all right,” agreed harry, “but we’ll have to keep out of the way of the crew bringing in stores let’s go.”

they scrambled down the ladder and reached the rivet-studded deck of the neptune. there was a lull in the steady stream of boxes being carried into the interior and they hurried through the main hatch and into the conning tower, then down into the main control room.

andy looked about in amazement at the compactness of the instruments in the “brains” of the submarine. there was not an inch of waste space in the spotlessly white interior of the steel fish.

harry led them through the forward engine room and into the crew quarters where double-decked bunks lined the walls. just ahead were the officers’ quarters, slightly better furnished than those of the crew and beyond this was the radio cubby where harry would practically live from the time they left the brooklyn shipyard until they returned from the desolate ice wastes of the far north.

they went on ahead into the room usually used as a torpedo room. this had been fitted with scientific equipment for sounding the ocean depths, and determining the material at the bottom of the arctic. in addition to the scientific paraphernalia, the forward room contained the all important rescue chambers. in this room was located the powerful drill which was capable of boring fifty feet upward straight through the ice, opening a tunnel large enough for a man to wriggle through in case the submarine became trapped by ice. there was also an escape passage through the forward torpedo tubes.

the inspection of the forward half of the sub completed, they turned to the after quarters. another large engine room was located after the main control room and beyond this was another room with double-decked bunks while just back of that was the galley.

“you’ve got a place to cook food,” said bert, “but where do you eat?”

“just about any place we find convenient,” replied harry. “there are a number of folding tables that can be pulled out in the crews’ quarters but if the going is rough or we’re busy, we take on food when and where we can get it.”

“when you’re pitching around on the north atlantic and trying to connect a little food with that hungry mouth of yours, just remember what a pleasant time i’ll be having on the goliath where there’s plenty of room to stretch and plenty of room to eat,” said bert.

“i’ll probably remember that a good many times,” grinned harry, “but if you radio me a description of some of those nice meals of yours. i’ll refuse to answer.”

they completed their inspection of the neptune and had climbed back to the wharf when a roadster rolled through the shipyard gate.

“just a minute, fellows,” said harry. “here comes gilbert mathews. i’d like to have you meet him.”

the commander of the neptune was tall and broad-shouldered. his walk was vigorous and he was hatless. his brown hair was slightly gray at the temples and he might be anywhere from 35 to 45 years old.

“hello, harry,” he said as he came up. “your radio equipment all ready?”

“everything’s tested and in fine shape,” replied the radio operator. “i’d like to have you meet my friends.”

“delighted,” said the explorer, and he greeted blatz, bert and andy cordially.

“i’ve had some very pleasant conferences with your father,” he told andy. “will we meet at the north pole this summer?”

“i sincerely hope so,” replied andy. “bert is chief radio operator on the goliath and i will make the trip as assistant to captain harkins.”

“then i am sure that we will meet again,” replied mathews. he turned to harry.

“did the orders reach you at your hotel before you left this morning?” he asked.

“no sir,” replied harry.

“then this will come as somewhat of a surprise,” smiled mathews. “we’ll leave at sunrise and every member of the crew has been ordered on board tonight.”

“it certainly is a surprise,” gasped harry, “but i’ll be aboard ship tonight.”

“you’re leaving almost two weeks earlier than you had first planned,” said andy.

“conditions in the arctic are more open than they have been for a number of years,” replied the explorer, “and i am anxious to get the neptune into the ice as soon as possible.”

“we probably will not see you again,” said andy, “but we wish you every good fortune and we’ll see you at the north pole.”

“thank you for your good wishes,” replied mathews. “in return, i wish the goliath a fair voyage and a fast one.”

the explorer left them and hurried down the ladder to supervise the final preparations for the departure of the neptune.

harry was busy the remainder of the day, finishing the task of getting his kit together and sending goodbye telegrams to relatives, for his parents lived in illinois and would not be able to reach new york before sailing time.

hotel reporters learned that the assistant pilot of the goliath was in the city and when they returned to the hotel in late afternoon, half a dozen were waiting for andy.

they plied him with questions. how long would it be before the goliath was ready to take the air; what would the big ship do; where would it go on its trial flights; was it true that attempts had been made to destroy the ship in its hangar; when would it start on the cruise into the arctic regions?

to all these questions andy was able to give only the most general of answers for he was bound in secrecy not to reveal definite information about the goliath or the plans for its trial flights. andy and his friends posed while flashlights flared but finally they were alone in their rooms.

harry had finished the score of small tasks which had been necessary when the final sail order, was given and he stretched out on one of the beds, his hands clasped above his head.

“tonight we’re all here together,” he said. “tomorrow i’ll be going down the sound in the tin fish; next week you’ll be aloft as the goliath tries its wings, and the next time we meet will be at the north pole. believe me, that’s adventure.”

“how i envy you all,” said blatz, his voice low and earnest, and andy actually felt sorry for the european whom he had come to firmly suspicion. if he could wipe those doubts out of his mind, he would thoroughly like blatz for the foreigner was a born airman and would be a real asset to the technical staff of national airways.

“when you sail away for the north pole in the goliath,” he told andy, “i’ll stay on the ground at bellevue and watch you fade into the north but i’ll glory with you in success.”

“i’m hungry,” announced bert. “let’s go down and get something to eat. if we sit around here we’ll all get blue for we’re going to miss harry a lot. there’s just this one consolation. we’ll be able to talk back and forth daily on our low wave sets unless the arctic puts up a wall of static we can’t break through.”

their last meal together was a quiet affair despite bert’s efforts to make it jolly and cheerful. with harry going aboard ship within the next hour or so and the neptune casting off at dawn, they knew the start of the great adventure was at hand and it awed them all.

a messenger paged harry in the dining room and handed him a telegram. the neptune’s radio operator tore it open with fingers that shook just a little and read it hungrily. his face whitened for a moment and he folded the message carefully and placed it in an inner pocket. there was a suspicion of a tear in one eye.

“a wire from dad and mother,” he said. “they’re the best ever.”

an hour later they stepped out of a taxi on the brooklyn wharf. lights glowed over the neptune; cars hurried up to disgorge other members of the crew, newspaper men were buzzing around, flashlights blazed and over the whole scene there was a feeling of tension.

gilbert mathews was at the head of the ladder, checking in every man as he came aboard. harry reported and was checked off the list. he turned to his friends from bellevue.

“i can’t say very much,” he told them. “everything is sort of choked up in my throat. bert, old scout, i’ll be tuning up for your messages. don’t forget me.”

“i won’t,” promised the goliath’s operator.

“so long, fellows,” said harry and he turned and hastened down the ladder to the deck of the neptune. he paused for a moment and waved before stepping inside the steel hull.

when they returned to their hotel, blatz stopped at a newsstand to buy an early edition of one of the morning papers. they were so much more comprehensive than the rubanian papers to which he had been accustomed and he thoroughly enjoyed reading them. in the quiet of his room he digested the news of the day. a story on an inside page caught and held his attention. the dateline was “kratz, rubania.” the story told of the growing unrest against the regime of dictator reikoff, adding that this bad feeling was centered in the powerful air corps, the largest unit of the rubanian army.

blatz knew what they meant. reikoff had been making unjust demands of his airmen and he was sitting on an open powder keg which was likely to explode with disastrous results to himself. blatz almost wished that revolution would sweep the country and rid rubania of its dictator. he was thoroughly disgusted and out of sympathy with the task to which he had been assigned, that of destroying the goliath, and he would welcome any opportunity to escape but as long as reikoff lived and ruled it would mean death for blatz if he failed to carry out his mission.

andy stepped through the door which connected the double room.

“any objections to our returning to bellevue in the morning?” he asked.

“no, why?” replied blatz.

“oh, there’s no reason for us to stay on longer here but i thought you might have some business over on the east side to transact.”

andy’s keen eyes were watching blatz’s face, searching for some change of expression that would indicate his alarm. there was none; the civilian observer outwardly appeared cool and unruffled but it was well that andy could not see the flash of fear that seared across his mind. it was true, then, that andy did suspect him. he was warning him in this way to watch his step. undoubtedly he would tell the secret service. if he, blatz, were to accomplish his mission of destruction it must be immediately after his return to bellevue.

“there is nothing to keep me in the city,” replied blatz, “and i am anxious to get back and see the finishing touches put on the goliath.”

“then we’ll get an early start,” said andy, “drop down the harbor and say goodbye to the neptune and then head for home. we ought to be there in time for lunch.”

they were up shortly after dawn but it was eight o’clock by the time they reached the airport of the national airways in jersey, had stowed their baggage in the monoplane and were ready to take the air. andy took over the controls, blatz climbed in beside him and bert stowed his more ample bulk in a chair just behind and beside a window where he could wave when they passed the neptune.

satisfied that the motor of the monoplane was functioning perfectly, andy sent the plane speeding over the crushed rock runway and into the slanting rays of the sun. he circled the field until he had plenty of altitude, and then cut across the jersey flats where the blue atlantic gleamed in the distance.

the neptune must have started at the crack of dawn, for the submarine was far down the bay when they finally picked it up. the neptune was running on the surface at ten knots an hour, its sharp nose cleaving through the sparkling waves and its decks almost awash. the main hatch was open and half a dozen of the crew were on top of the conning tower.

andy sent the monoplane down in a gentle glide, levelled off, and skimmed over the water with motor on full. they flashed past the neptune, raced out to sea, turned and roared back: someone on the conning tower was waving frantically.

the three in the monoplane caught a fleeting glimpse of harry as they sped past. the neptune was off, headed for plymouth, england, on the first leg of its long and adventurous trip into the arctic.