Just clear of the head of the companion staircase and leading up one side of the pilot-house was another light staircase of open grid-work leading to the floor above, which, at a height of seven feet, spanned the building from side to side. This floor was also of light open gridwork, affording easy verbal communication between persons occupying the different stories in the pilot-house. Through this open grid-floor could be seen various apparatus, the objects of which the new-comers were naturally anxious to learn; and to this floor the professor accordingly led his companions up the staircase.

The first object to which he directed attention was a long straight bar of aethereum handsomely moulded into the form of a thick cable, and finished off at the outer end with the semblance of a "Matthew Walker"

knot. This bar issued at its inner end from a handsomely panelled and moulded casing which extended down through both floors of the pilot- house, presumably covering in and protecting the mechanism with which the bar was obviously connected.

"This," said the professor, laying his hand on the bar, "is the steering apparatus--the tiller as you call it--of the ship. It moves, as you see, in all directions, and communicates a corresponding movement to the propeller--as you may see, if you will take the trouble to look out through one of those windows."

The trio immediately did so, and saw, as the professor had stated, that with every movement of the tiller, right or left, up or down, the propeller inclined itself at a corresponding angle. A handsome binnacle compa.s.s stood immediately in front of the tiller, but the professor did not call attention to it, rightly a.s.suming that his companions were fully acquainted with its use and purpose.

On the professor's right, as he stood at the tiller, was an upright lever working in a quadrant, and communicating, like the tiller--and indeed all the other apparatus--with the interior of the ship.

"This," said the professor, directing attention to the lever, "is the lever which controls the valves of the main engines. I have fashioned and arranged it exactly like the corresponding lever in a locomotive.

Placed vertically, thus, the engines remain motionless. Thrown forward, thus, the engines will turn ahead. And thrown backward, thus, they will turn astern. That is simple enough. And so is this," directing attention to a dial on his left hand which stood facing him. The dial had a single hand which was obviously intended to travel over a carefully graduated arc of ninety degrees painted on the dial-face, and which, in addition to the graduations, was marked in the proper positions with the words "Stop;" "Quarter speed;" "Half speed;" "Full speed;" and also with two arrows pointing in opposite directions marked "On" and "Off" respectively. Just beneath the dial was a small wheel with a crank-handle projecting from one of its spokes, and on this crank-handle the professor now laid his hand.

"This," he said, "regulates the valve which admits vapour into the engine; and the dial-hand shows the extent to which the valve is opened.

Turn the wheel in the direction of the arrow marked 'On'--thus, and you admit vapour into the engine. You will observe that, as I turn the wheel, the hand on the dial travels over the arc and indicates the extent to which the valve is open. There; now it is fully open, and the cylinders are full of vapour." Then he quickly reversed the wheel and sent the index hand back to "Stop," keeping a wary eye on his companions as he did so.

"These are dangerous things to meddle with," he remarked apologetically.

"The engines are of one hundred thousand horse-power; and, full as the ship now is of air at the atmospheric pressure, they would drive her irresistibly along the ground and through all obstacles. I must beg that none of you will meddle with the machinery until you are fully acquainted with its tremendous power."

"What is this pendulum-looking affair, professor?" asked the colonel, pointing to a pendulum the point of which hung in a shallow basin-like depression thickly studded with needle-points which the pendulum just cleared by a hair's-breadth.

"That," explained the professor, "is a device for automatically regulating the balance, or 'trim' as you call it, of the ship when she is floating in the air. You will readily understand that when freed of air, and thus deprived of weight, as it were, the most trifling matter will suffice to derange her equilibrium; one of us, walking from side to side, or from one end of the deck to the other, would very seriously incline her from the horizontal, and thus alter the direction of her flight, possibly with disastrous results; so I have devised this little apparatus to prevent all that. This pendulum, as you see, is so delicately poised that it will instantly respond to the slightest deviation from a horizontal position, and, swaying over one of these needle-points, will send an electric current to the air-pump, causing it to promptly inject a sufficient quant.i.ty of air into the proper chamber to restore the equilibrium. But, as we may desire occasionally to direct the flight of the ship in an upward or a downward direction, I have so arranged matters that the apparatus shall be thrown out of gear when the tiller is sloped in either direction out of the horizontal; and as we shall not require it when the ship is on or below the surface of the ocean, I have here provided a small k.n.o.b by pressing which inwards the apparatus can also be thrown out of gear until it is again wanted."

"Excellent!" exclaimed the baronet. "I must again congratulate you, professor, on your truly wonderful forethought. And what is this, pray?"

"That," said the German, "is the controlling lever of the air-pump.

When we want to sink into the depths of the ocean, I thrust this lever over--so; and the pump at once begins to pump air into the air- chambers."

"_Out_ of them, I suppose you mean," interrupted the baronet.

"_Into_ them, I mean," insisted the professor. "You must understand,"

he continued, noting the baronet's look of astonishment, "that air, like everything else, has _weight_. Feathers are light; but you may pack them so tightly into a receptacle as to make them very weighty; and so is it with air: the more air you force into a receptacle of given size the heavier you make that receptacle; and, provided that both your forcing apparatus and your receptacle are strong enough to endure the tremendous pressure, you may at last force enough air into the receptacle to sink it. And that is precisely what we shall do; we shall force air into our air-chambers until the ship is on the point of sinking, and we shall then close the valves, stop the air-pump, and, opening the sea-c.o.c.ks of the water-chambers, admit water enough into the ship to send her to the bottom like a stone."

"Well! you astonish me, I freely admit," gasped the baronet. "This is the first time I ever heard of a ship being sunk by filling her with air. And then the cool way in which you talk of our 'sinking to the bottom like a stone!' I undertook this enterprise because I wanted to experience a new sensation; and it appears to me that there are a good many of them in store for me. However, it is all right; go on with your explanations, my dear sir."

"These," said the professor, indicating several levers marked with distinguishing labels ranged all along one side of the pilot-house, "are the levers opening and closing the valves of the air and water chambers, and need no further description. This," he continued, pointing to a small box with a little k.n.o.b projecting out of the top of it, "is the apparatus for firing our torpedo sh.e.l.ls."

The baronet glanced mutely round at his companions, and shrugged his shoulders expressively, as who should say, "What next?"

The colonel and the lieutenant nodded approvingly, however, and the latter said:

"That is capital, professor; we ought to have the means of fighting the ship, if necessary; but I was beginning to fear you had overlooked that matter, having seen no provision for anything of the kind. But where is your torpedo port? you omitted to point that out to us when we were under the ship's bottom."

"There was nothing to show," replied the professor; "and I can explain the matter just as well up here as I could have done when we were down below. The conical point which forms the extreme forward end of the ship is solid and movable. Under ordinary circ.u.mstances it remains firmly fixed in position; but when it becomes necessary to fire a torpedo-sh.e.l.l the solid point is made to slide in along a grooved tube for a certain distance; the sh.e.l.l is then placed in the tube and fired, when the solid point follows it out and becomes again securely fixed in its former position. In addition to this arrangement, I have two large guns which can be worked through ports in the dining-saloon, and six wonderful magazine rifles invented by a Mr Maxim, a friend of mine.

They are perhaps the most wonderful pieces of mechanism in the ship, for when the first shot has been fired they will go on firing themselves at the marvellous rate of six hundred shots per minute so long as you keep them supplied with cartridges. Then I have also provided an ample supply of ordinary guns and rifles, swords, pikes, pistols, and in fact everything we are likely to require for the purposes of sport or defence. These small k.n.o.bs afford the means of lighting the electric lamp in the lantern on the top of the pilot-house and those in the bow and stern of the ship. And that is all to which I think I need direct your attention here at present. Now, if you please, we will go down and look at the machinery."

The party accordingly left the pilot-house and directed their steps below by way of the grand staircase. At the bottom of this they found themselves upon a s.p.a.cious landing magnificently carpeted, and lighted at each end by a circular window in the side of the ship. In front of them as they descended the staircase, and at a distance of about twelve feet from its base, a part.i.tion stretched from side to side of the ship, evidently forming one of the saloon bulkheads. Along the face of this a series of Corinthian pilasters, supporting a n.o.ble cornice at the junction of wall and ceiling, divided up the part.i.tion into a corresponding number of panels, which were enriched with elegant mouldings of fanciful scroll-work and painted in creamy white and gold.

In two instances, however, at points which divided the part.i.tion into three equal parts, the panels were replaced by handsome ma.s.sively moulded doors of unpainted aethereum, imparting a very rich and handsome effect. These doors were, however, closed, and the curiosity of the new-comers as to what was to be seen on the other side of them had to remain for a short time ungratified.

Pa.s.sing round to the back of the grand staircase (in which direction lay the sleeping apartments, bath-rooms, and domestic offices) they found themselves at the head of another staircase much narrower than the former. The one now before them was only about four feet wide, winding cork-screw fashion round the tube which encased the communications between the pilot-house and the engine-room, etcetera, and it was in its turn encased in a cylindrical bulk-head, in which, on their way below, they pa.s.sed several doors giving access, as the professor explained, to the different decks.

Winding their way downward for a considerable distance they at length reached the foot of the staircase and pa.s.sed at once through a doorway marked "Engine Room." The first sensation of those who now visited this apartment for the first time was disappointment. The room, though full of machinery, was small, absurdly so, it seemed to them. So also with the machinery itself. The main engines, consisting of a pair of three- cylinder compound engines, though made throughout of aethereum, and consequently presenting an exceedingly handsome appearance, suggested more the idea of an exquisite model in silver than anything else, the pair occupying very little more s.p.a.ce than those of one of the larger Thames river steamers. The impression of diminutiveness and inadequacy of power pa.s.sed away, however, when the professor informed his companions that the vapour would enter the high-pressure cylinder at the astounding pressure of five thousand pounds to the square inch, and that, though the engines themselves would only make fifty revolutions per minute, the propeller, would be made, by means of speed-multiplying gear, to revolve at the rate of one thousand times per minute in air of ordinary atmospheric pressure.

"But how on earth do you manage to get your vapour up to that tremendous pressure?" asked the colonel.

"Oh!" answered the professor, "that is a mere matter of mixing.

According to the proportions in which the crystals and the acid are mingled together, so is the pressure of the vapour."

"And how do you mingle them together?" asked the lieutenant.

"This," said the professor, leading them up to a small boiler-like vessel, "is the generator. The crystals are placed in a hopper at one end, and the acid in that small tank at the other, from whence they are respectively conducted along tubes into a small well in the bottom of the generator, where, their proportions being regulated by the size of the tubes through which they pa.s.s, they mingle and generate a vapour having a pressure of five thousand pounds on the square inch. See, there is the gauge, and it is now registering a pressure of five thousand pounds."

"Good Heavens, man!" exclaimed the baronet, starting back; "you don't mean to say that your generator is _now_, at this moment, subjected to that enormous pressure of more than two tons per square inch? Supposing it exploded, what would become of us?"

"We should be consumed in an instant by the fierce heat of the liberated vapour," replied the professor calmly. "But," he continued, "you need have no apprehension of an explosion. When that generator was being made I had a second one constructed at the same time, precisely similar in every respect, and this second one I tested to destruction, with the satisfactory result that it endured without distress a pressure of thirty-five tons per square inch, showed the first signs of weakness when it became subjected to a pressure of thirty-eight tons, and burst at a joint when under a pressure of forty-three tons per square inch.

You may therefore feel quite satisfied that the generator is fully equal to a continuous pressure of at least fifteen tons, instead of the trifle over two which it will have to sustain."

The remainder of the machinery possessing no very startling or novel features, it was pa.s.sed by with merely an admiring glance at its exquisite finish; and the quartette, leaving the engine-room, pa.s.sed round on the other side of the spiral staircase to a room marked "Diving Room."

Entering this they found themselves in an apartment about twenty feet square, one side of which was wholly occupied by four cupboards labelled respectively "Sir Reginald Elphinstone," "Colonel Lethbridge,"

"Lieutenant Mildmay," and "Von Schalckenberg."

"This," explained the professor, "is the room wherein we shall equip ourselves for our submarine rambles; and here," opening one of the cupboards, "are the costumes which we shall wear upon such occasions."

The opened cupboard contained an ordinary indiarubber diving-dress, a sort of double knapsack, a number of heterogeneous articles, and, lastly, a suit of armour.

"Why, professor, what, in the name of all that is comical, is the meaning of this? Are we to walk forth among the fishes equipped like the knights of old?" asked the baronet, pointing to the armour.

"I will explain," said the professor. "In an ordinary diving-dress a man can only descend to a depth of something like fifteen fathoms.

Instances have certainly occurred where this depth has been exceeded, a Liverpool diver named Hooper having descended as far as thirty-four fathoms, if my information is correct; but this was quite an exceptional circ.u.mstance; and, as I have said, fifteen fathoms may be taken as the average depth at which a man can move about and work in comfort. The reason for this limit is that beyond it the pressure of the water on the exposed hands is so great as to drive the blood to the head and bring on a fainting fit, if nothing worse; besides which, the volume of air inside the dress necessary to counteract the outside pressure of the water would be so great as to speedily result in suffocation. Now, if our explorations were limited to a depth of fifteen fathoms only they would hardly be worth the undertaking; so I have devised these suits of armour, in which we may safely explore the profoundest depths of the ocean to which the _Flying Fish_ can penetrate. The armour is, as you see, composed of a number of small scales or plates of aethereum, and is so constructed that, whilst it is perfectly flexible, permitting the utmost freedom of movement to the wearer, it is also absolutely water- tight and incompressible, no matter how great the exterior pressure to which it is subjected. The wearer of it will consequently be perfectly protected at all points from the enormous water pressure; and he will be able to breathe in comfort, his air being supplied to him at the normal atmospheric pressure. In equipping himself the diver will first don the india-rubber diving-dress in the usual way. Then he will a.s.sume this double-haversack, the larger chamber of which, worn on the back, will contain a supply of air, whilst the smaller of the two, worn on the chest, is charged with a supply of chemicals for the purification of the air after it has been breathed. The two are connected together by a pair of flexible tubes, as you may perceive, and the mere expansion and contraction of the chest, in the act of breathing, sets in motion the simple apparatus which produces the necessary circulation of air between the two chambers. Having secured this haversack in position the diver next dons his body armour, and straps about his waist this belt, with its electric lamp and its dagger. The dagger, as you see, is double- bladed; it has a haft of insulating material, and the blades have connected to them this insulated wire at the point where the blades and the handle unite. You thus have a weapon which, on being plunged into the body of a foe, not only inflicts a severe wound, but also administers an electric shock of such terrible intensity as must result in instant death. The last portion of the armour to be a.s.sumed is the helmet, on the top of which is securely fixed an electric lamp, which, with the aid of the one at the belt, will give us, I imagine, as much light as we are likely to need.

"Having donned our armour we pa.s.s out of this chamber into the next, which I call the chamber of egress, carefully closing the door behind us."

The professor, suiting the action to the word, ushered his companions into the next chamber, closing the door behind him, and they found themselves in a small room some ten feet square by seven feet in height.

This room, in common with the diving-room, was brilliantly lighted by an electric lamp inclosed in a lantern of abnormally thick gla.s.s.

"Arrived here," continued the professor, "we are all ready to sally forth upon our submarine explorations; all we have to do therefore is, first to fill the chamber with water by means of this valve, then open the trap-door and step forth upon the bottom of the sea."

As the professor said this he released the fastenings of the door, and it fell down, forming a sort of inclined plane, over which they pa.s.sed, to find themselves once more on the solid earth, under the ship's bottom, with the starboard bilge-keel rising like a wall of silver before them. They pa.s.sed along the lane formed by this keel and the cylindrical bottom of the ship, and then stepped back with one accord to take another glance aloft at the huge bulk of the ship as she towered high above them. They now became conscious of the sounds of vigorous hammering and of men's voices in the direction of the river gable of the building shed, and on looking in that direction they saw that the contractor, whom the professor had engaged for the purpose, was already at work with his men removing the boarding which had hitherto concealed the _Flying Fish_ from pa.s.sers-by on the river, thus making a way for the exit of the ship a little later on.

The little party had re-entered the hull by way of the trap-door, and the professor had just made the fastenings once more secure, when, far away aloft from somewhere within the recesses of the ship, they heard the loud, sonorous, sustained note of a gong.

"Ah, that is good!" exclaimed Herr von Schalckenberg, rubbing his hands; "that is the dinner gong; and I am hungry. Come, my friends, to the dining saloon, and let us partake of the first of, I hope, many pleasant meals on board the _Flying Fish_."

CHAPTER FOUR.

THE NOVEL BEGINNING OF A SINGULAR VOYAGE.