The two men watched it for several minutes; all the time it seemed to be growing larger and brighter till, after a while, they saw that the light came from something shaped like a ship, sharp at both ends, and covered with oval glass. As it slowly rose to the surface they saw that it contained five or six men, sitting in easy chairs and reclining on luxurious divans. One of them sat at a sort of pilot-wheel and was directing the course of the strange craft, which was moving as gracefully as a great fish.

Then the young men saw the man at the pilot-wheel raise his hand, and from the water came the musical notes of a great bell. The vessel stopped, and one of the men sprang up and raised an instrument that looked like a telescope to his eyes. With this he seemed to be closely searching the lake shores, for he did not move for several minutes. Then he lowered the instrument, and when the bell had rung again, the vessel rose slowly and perpendicularly to the surface and glided to the shore within twenty yards of where the adventurers stood.

“Could they have seen us?” whispered Thorndyke, drawing Johnston nearer the side of the cliff.

“I think so; at all events, they are between us and the outlet; we may as well make the best of it.”

The men, all except the pilot, landed, and a dazzling electric search-light was turned on the spot where Thorndyke and Johnston stood. For a moment they were so blinded that they could not see, and then they heard footsteps, and, their eyes becoming accustomed to the light, they found themselves surrounded by several men, very strangely clad. They all wore long cloaks that covered them from head to foot and every man was more than six feet in height and finely proportioned. One of them, who seemed to be an officer in command, bowed politely.

“I am Captain Tradmos, gentlemen, in the king's service. It is my duty to make you my prisoners. I must escort you to the palace of the king.”

“That's cool,” said Johnston, to conceal the discomfiture that he felt, “we had no idea that you had a kingdom. We have tramped all over this island, and you are the first signs of humanity we have met.”

He would have recalled his words before he had finished speaking, if he could have done so, for he saw by the manner of the captain that he had been over bold.

“Follow me,” answered the officer curtly, and with a motion of his hand to his men he turned toward the odd-looking vessel.

The two adventurers obeyed, and the cloaked men fell in behind them. Neither Johnston nor Thorndyke had ever seen anything like the peculiar boat that was moored to the rocky shore. It was about forty feet in length, had a hull shaped like a racing yacht, but which was made of black rubber inflated with air. It was covered with glass, save for a doorway about six feet high and three feet wide in the side, and looked like a great oblong bubble floating on the still dark water. As they approached the searchlight was extinguished, and they were enabled to see the boat to a better advantage by the aid of the electric lights that illuminated the interior. It was with feelings of awe that the two adventurers followed the captain across the gang-plank into the vessel.

The electric light was brilliantly white, and in various places pink, red and light-blue screens mellowed it into an artistic effect that was very soothing to the eye. The ceiling was hung with festoons of prisms as brilliant as the purest diamonds, and in them, owing to the gently undulatory movement of the vessel, colors more beautiful than those of a rainbow played entrancingly. Rare pictures in frames of delicate gold were interspersed among the clusters of prisms, and the floor was covered with carpets that felt as soft beneath the foot as pillows of eider-down.

As he entered the door the officer threw off his gray cloak, and his men did likewise, disclosing to view the finest uniforms the prisoners had ever seen. Captain Tradmos's legs were clothed in tights of light-blue silk, and he wore a blue sack-coat of silk plush and a belt of pliant gold, the buckles of which were ornamented with brilliant gems. His eyes were dark and penetrating, and his black hair lay in glossy masses on his shoulders. He had the head of an Apollo and a brow indicative of the highest intellect.

Leaving his men in the first room that they entered, he gracefully conducted his prisoners through another room to a small cabin in the stern of the boat, and told them to make themselves comfortable on the luxurious couches that lined the circular glass walls.

“Our journey will be of considerable length,” he said, “and as you are no doubt fatigued, you had better take all the rest you can get. I see that you need food and have ordered a repast which will refresh you.” As he concluded he touched a button in the wall and instantly a table, laden with substantial food, rare delicacies and wines, rose through a trap-door in the floor. He smiled at the expressions of surprise on their faces and touched a green bottle of wine with his white tapering hand.

“The greater part of our journey will be under water, and our wines are specially prepared to render us capable of subsisting on a rather limited quantity of air during the voyage, so I advise you to partake of them freely; you will find them very agreeable to the taste.”

“We are very grateful,” bowed Thorndyke, from his seat on a couch. “I am sure no prisoners were ever more graciously or royally entertained. To be your prisoner is a pleasure to be remembered.”

“Till our heads are cut off, anyway,” put in the irrepressible American.

Tradmos smiled good-humoredly.

“I shall leave you now,” he said, and with a bow he withdrew.

“This is an adventure in earnest,” whispered Johnston; “my stars! what can they intend to do with us?”

“One of the first things will be to take us down to the bottom of this lake where we saw them awhile ago, and I don't fancy it at all; what if this blasted glass-case should burst? We may have dropped into a den of outlaws on a gigantic scale, and it may be necessary to put us out of the way to keep our mouths closed.”

“I am hungry, and am going to eat,” said the American, drawing a cushioned stool up to the table. “Here goes for some of the wine; remember, it is a sort of breath-restorer. I am curious enough not to want to collapse till I have seen this thing through. He said something about a palace and a king. Where can we be going?”

“Down into the centre of the earth, possibly,” and the handsome Englishman moved a stool to the table and took the glass of green-colored wine that Johnston pushed toward him. “Some scientists hold that the earth is filled with water instead of fire. Who knows where this blamed thing may not take us? Here is to a safe return from the amphibious land!”

Both drank their wine simultaneously, lowered their glasses at the same instant, and gazed into each other's eyes.

“Did you ever taste such liquor?” asked Thorndyke, “it seems to run like streams of fire through every vein I have.”

Johnston shook his head mutely, and held the sparkling effervescing fluid between him and the light.

“Ugh! take it down,” cried the Englishman, “it throws a green color on your face that makes you look like a corpse.” Johnston clinked the glass against that of his companion and they drained the glasses. “Hush, what was that?” asked Thorndyke.

There was a sound like boiling water outside and as if air were being pumped out of some receptacle, and the vessel began to move up and down in a lithe sort of fashion and to bend tortuously from side to side like a great sluggish fish. Through the partitions of glass they saw one of the men closing the door, and in a moment the vessel glided away from the shore. The men all sank into easy positions on the couches, and delightful music as soft as an Aeolian lyre seemed to be breathed from the walls and floor. Then the music seemed to die away and a bell down in the vessel's hull rang.

“We are in the middle of the lake,” said Thorndyke, looking through the glass toward the black cliffy shore; “the next thing will be our descent. I wonder——”

But he was unable to proceed, and Johnston noticed in alarm that his eyes were slightly protruding from their sockets. The air seemed suddenly to become more compact as if compressed, and the water was set into such violent commotion that it was dashed against the glass sides in billows as white as snow. Then Johnston found that he could not breathe freely, and he understood the trouble of the Englishman.

Captain Tradmos came suddenly to the door. He was smiling as he motioned toward the wines on the table.

“You had better drink more of the wine,” he advised sententiously.

Both of the captives rushed to the table. The instant they had swallowed the wine they felt relieved, but were still weak. The captain bowed and went away. Thorndyke's hand trembled as he refilled his friend's glass. “I thought I was gone up,” he said, “I never had such a choky sensation in my life; you are still purple in the face.”

“Eat of what is before you,” said the captain, looking in at the door; “you cannot stand the increasing pressure unless you do.”

They needed no second invitation, for they were half-famished. The fish and meat were delicious, and the bread was delightfully sweet.

“Look outside!” cried Johnston. The water was now still, but it was gradually rising up the sides of the boat, and in a moment it had closed over the crystal roof. Both of the captives were conscious of a heavy sensation in the head and a dull roaring in the ears. Down they went, at first slowly and then more rapidly, till it seemed to them that they had descended over a thousand feet. Great monsters like whales swam to the vessel, as if attracted by the lights, and their massive bodies jarred against the glass walls as they turned to swim away. They sank about five hundred feet lower; and all at once the lights went out, and the boat gradually stopped.

It was at once so dark that the two captives could not see each other, though only the width of the table separated them. Everything was profoundly still; not a sound came from the men in the other rooms. Presently Thorndyke whispered, “Look, do you see that red light overhead?”

“Yes,” said Johnston, “it looks like a star.”

“It is our bonfire,” said Thorndyke, “that's what betrayed us.”

Again the vessel began to sink, and more rapidly than ever; indeed, as Thorndyke expressed it, he had the cool feeling that nervous people experience in going down quickly in an elevator.

“If we go any lower,” he added, as the great rubber hull seemed to struggle like some living monster, “the sides of this thing will collapse like an egg-shell and we will be as flat as pancakes.”

“You need not fear, we have much lower to go!” It was the captain's voice, but they could not tell from whence it came. Then they heard again the seductive music, and it was so soothing that they soon fell asleep.

They had no idea how long they had slept, but they were awakened by the ringing of a bell and felt the vessel was coming to a stop. They were still far beneath the surface; indeed, the boat was resting on the bottom, for in the light of two or three powerful search-lights they saw a wide succession of submerged hills, vales, and rugged cliffs. Before them was a great mountain-side and in it they saw the mouth of a dark tunnel. They had scarcely noticed it before the vessel rose a little and glided toward the tunnel and entered it. Through the glass walls they could see that it was narrow, and that the ragged sides and roof were barely far enough apart to admit them.

Suddenly one of the men came in and drew a curtain down behind them, and, with a vexed look on his face retired.

When he was gone Johnston put his lips close to Thorndyke's ear and whispered:

“Did you see that?”

“See what?”

“Just as he drew the curtain down I saw what looked to me like a cliff of solid gold. It had been dug out into a cavern in which I saw a vessel like this, and men in diving suits digging and loading it.”

This took the Englishman's breath away for a moment, then he remarked: “That accounts for the heel-tap we found; who knows, these people may be possessors of the richest gold and silver mines on earth.”

The bell rang again. “We are rising,” said Johnston. “If this is the only way of reaching the king's domain, we could never get back to civilization unless they release us of their own accord, that's certain!”

“Heavens, isn't it still!” exclaimed the Englishman. “The machinery of this thing moves as noiselessly as the backbone of an eel. I wish I could understand its works.”

“I am more concerned about where we are going. I tell you we are being taken to some wonderful place. People who can construct such marvels of mechanical skill as this boat will not be behind in other things; then look at the physiques of those giants.”

Just then the man who had drawn down the shade came in and raised it. Both the captives pretended to be uninterested in his movements, but when he had withdrawn they looked through the glass eagerly.

“See,” whispered Thorndyke, in the ear of his companion, “the walls are close to us, and are as perpendicular as those of the lake in which they found us.”

Johnston said nothing. His attention was riveted to the walls of rock; the vessel was rising rapidly. An hour passed. The soft music had ceased, and the air seemed less dense and fresher. Then the waters suddenly parted over the roof and ran in crystal streams down the oval glass.

They were on the surface, and the vessel was slowly gliding toward the shore which could not be seen owing to there now being no light except that inside the boat. Captain Tradmos entered, followed by two of his men holding black silken bandages.

“We must blindfold you,” he said; “captives are not allowed to see the entrance to our kingdom.”

Without a word they submitted.

“This way,” said the captain kindly, and, holding to an arm of each, he piloted them out of the vessel to the shore. Then he led them through what they imagined to be a long stone corridor or arcade from the ringing echoes of their feet on the stone pavement. Presently they came to what seemed to be an elevator, for when they had entered it and sat down, they heard a metallic door slide back into its place, and they descended quickly.

They could form no idea as to the distance they went down; but Thorndyke declared afterward that it was over ten thousand feet. When the elevator stopped Captain Tradmos led them out, and both of the captives were conscious of breathing the purest, most invigorating air they had ever inhaled. Instantly their strength returned, and they felt remarkably buoyant as they were led along over another pavement of polished stone.

Tradmos laughed. “You like the atmosphere?”

“I never heard of anything like it,” said Thorndyke. “It is so delightful I can almost taste it.”

“It was that which made Alpha what it is—the most wonderful country in the universe,” said the officer. “There is much in store for you.”

The ears of the two captives were greeted by a vague, indefinable hum, like and yet unlike that of a busy city. It was like many far-off sounds carefully muffled. Now and then they heard human voices, laughter, and singing in the distance, and the twanging of musical instruments.

Then they knew that they were entering a building of some sort, for they heard a key turn in a lock and the humming sound in the distance was cut off. They felt a soft carpet under their feet, and the feet of their guards no longer clinked on the stones.

When the bandages were removed they found themselves in a sumptuous chamber, alone with the captain. The brilliant light from a quaintly-shaped candelabrum, in the centre of the chamber, dazzled them, but in a few minutes their eyes had become accustomed to it.

Tradmos seemed to be enjoying the looks of astonishment on their faces as they glanced at the different objects in the room.

“It is night,” he said smilingly. “You need rest after your voyage. Lie down on the beds and sleep. To-morrow you will be conducted to the palace of the king.”

With a bow he withdrew, and they heard a massive bolt slide into the socket of a door hidden behind a curtain. The two men gazed at each other without speaking, for a moment, and then they began to inspect the room.

In alcoves half-veiled with silken curtains stood statues in gold and bronze. The walls and ceilings were decorated with pictures unlike any they had ever seen. Before one, the picture of an angel flying through a dark, star-filled sky, they both stood enchanted.

“What is it?” asked Thorndyke, finding voice finally. “It is not done with brush or pencil; the features seem alive and, by Jove, you can actually see it breathe. Don't you see the clouds gliding by, and the wings moving?”

“It is light—it is formed by light!” declared the other enthusiastically, and he ran to the wall, about six feet from the picture, and put his hand on a square metal box screwed to the wall.

“I have it,” he said quickly, “come here!”

The Englishman advanced curiously and examined the box.

“Don't you see that tiny speck of light in the side towards the picture? Well, the view is thrown from this box on the wall, and it is the motion of the powerful light that gives apparent life to the angel. It is wonderful.”

In a commodious alcove, in a glow of pink light from above, was a life-sized group of musicians—statues in colored metal of a Spanish girl playing a mandora, an Italian with a slender calascione, a Russian playing his jorbon, and an African playing a banjo. Luxurious couches hung by spiral springs from the ceiling to a convenient height from the floor, and here and there lay rugs of rare beauty and great ottomans of artistic designs and colors.

“We ought to go to bed,” proposed Thorndyke; “we shall have plenty of time to see this Aladdin's land before we get away from it.”

There were two large downy beds on quaintly wrought bedsteads of brass, but the two captives decided to sleep together.

Thorndyke was the first to awaken. The lights in the candelabrum were out, but a gray light came in at the top and bottom of the window. He rose and drew the heavy curtain of one of the windows aside. He shrank back in astonishment.