Submersion

“ Which operation followes the Submersion and sinking; and this it is, How the submersion of Solids in the water is effected.That in the Submersion that the Solid maketh, being depressed downwards by its proper Gravity, it comes to drive away the water from the place where it successively subenters, and the water repulsed riseth and ascends above its first levell, to which Ascent on the other side it, as being a grave Body of its own nature, resists: And because the descending Solid more and more immerging, greater and greater quantity of Water ascends, till the whole Sollid be submerged ”

“ And, therefore, applying the like discourse to our purpose, they say, that the difference of Figure will shew different effects, touching Natation and Submersion, but not conjoyned with any kind of Matter, but only with those Matters which, by their Gravity, are apt to resist the Velocity of the water, whence he that would elect for the Matter, Cork or other light wood, unable, through its Levity, to superate the Crassitude of the water, and of that Matter should forme Solids of divers Figures, would in vain seek to find out what operation Figure hath in Natation or Submersion ”

“ The easiest answer, and the one which most readily suggests itself, is that of a submersion of the continent at successive periods to allow the accumulation of these materials, and its subsequent elevation. I reject this explanation for the simple reason that the deposits show no sign whatever of a marine origin. ”

“ Therefore, we must of necessity conclude, that the said Fiery Exhalations ascend thorow the Water more swiftly than doth the Air; & the Air ascends more swiftly thorow the Water, than Fire thorow the Air. Exhalations do much more expeditiously ascend through the Water, than through the Air; and that, consequently, they are moved by the Impulse of the Ambient Medium, and not by an intrinsick Principle that is in them, of avoiding the Centre of the Earth; to which other grave Bodies tend.
The Authors confutation of the Peripateticks Causes of Natation & Submersion. ”

“ This opinion is, however, untenable; for the sinking down of the bed of the ocean is one of the means by which the gradual submersion of land is prevented. The depth of the sea cannot be increased at any one point without a universal fall of the waters, nor can any partial deposition of sediment occur without 564 the displacement of a quantity of water of equal volume, which will raise the sea, though in an imperceptible degree, even to the antipodes. ”

“ Passive Defence is chiefly confined to inundations, and is effected by letting out water in such a manner, that the level ground which lies round a fortified town or place may be entirely overflowed and become an inert stagnant pool. Mere submersion is, in fact, the distinguishing character of this species of defence, which does not afford any other movement than what naturally arises from the greater or lesser elevation of the waters, without the means of urging them beyond a given point. ”

“ It is well known that for every ten meters under water we oppose the pressure of one atmosphere—one kilogram to the square centimeter—and we must be prepared to dive to far greater depths.
When all these openings have been carefully closed and fastened, then begins the maneuver of submersion. The sea water is admitted into big open tanks. Powerful suction engines, in the central control of the boat, draw out [23] the air from these tanks so as to increase the rapid inrush of the water. ”

“ To satisfie all I may, to all doubts, I have been considering how by some other sensible Experiment I might demonstrate, how truly that little contiguous and superiour Air sustaines those Solids, which being by [Pg 39] nature apt to descend to the Bottom, being placed lightly on the water submerge not, unless they be first thorowly bathed ”

“ Up, up, up—until at last our craft shot bodily out of the waters into the sunlight and clean air. Panting and half senseless we ripped the doors open, breathed deep of the salt breezes. The waters on which the submarine floated were running in great seas, and from a hasty consultation of our instruments we saw that already the sea's level had risen several feet, and knew, too, as no others did, what was causing that rise and bringing doom upon the earth. ”

“ Submarine boats that can hit the target without being detected, go on cruises unattended for more than a thousand miles, and remain submerged for more than a day and a half, must be classed as efficient engines of warfare.
Since the submersible is designed to spend most of its time on the surface of the water like an ordinary boat, it must have considerable buoyancy, but it must also have some means of getting rid of this buoyancy quickly when submergence is necessary. The submarine proper has only from five to eight per cent. buoyancy, while some of the submersibles have twenty-five per cent. ”

“ The raft that I built and erected upon the ways was only as a cradle to support my submarine boat so that I could float the whole affair to the mouth of Stillwater Cove before allowing the latter to be submerged; for where I now was there was not water enough for my experiment, and I well knew that if my boat, which was to be of iron, was once launched, and should, by its displacement or specific gravity, go to the bottom, that I should be unable to raise it again, and that in the water directly in front of the ways it would touch the bottom even before it would be submerged. ”

“ Despite the perfection of the submarine the sea is still a great mystery to us. We know only its surface and its shallows. We have sounded a few deep holes and brought up samples of deep-sea life, but we have not been able to penetrate in person its profound depths and explore with our eyes and hands the world that is buried beneath its waves. Three quarters of the globe is covered by water and if we are to claim complete mastery of the earth we must find some way of descending into the heart of the ocean and exploring its deepest valleys. ”

“ Anon the light sank slowly down; the radiance faded away, and then we heard the angry and hollow roaring of the sea as it was sucked down into the mighty depth of some submarine crater or vortex, the physical construction of which was beyond our conception; but the reflux of the water boiled in hot and seething foam around us, while the spray that flew over the ship to leeward was warm, and became crusted salt in a moment, on the guns, booms, and shrouds. ”

“ The submarine is itself a shell, and as - 76 - it bursts out of it comes the life that animated it, in a new form, to dry and stretch its wings and presently dart into the air on them, henceforth a creature of the sun. Behind each remains its water-world husk, still clinging to the twig to which it crawled. Sometimes I put a finger into the water in front of the swimming insect, and it as readily crawls out on that as on a twig, but neither of us has yet had patience to wait thus till the transformation is complete. ”

“ The modern submersible usually forces itself under water, while still in a slightly buoyant condition, by its propellers and by the action of two sets of rudders, or hydroplanes, which are arranged along its superstructure and which tend to force it below the surface when they are given a certain inclination; but should the engines stop, the diving rudders, or hydroplanes, would become ineffective, and, because of the reserve buoyancy in the hull, the vessel would come to the surface. ”

“ Now there are sails fluttering on every sea, prodigious steamers throbbing like leviathans against wind and wave; harbors are built, and rocks and shoals removed; lighthouses gleam nightly from ten thousand stations on the shore; the great deep itself is sounded by plummet and diving-bell; the submarine world is disclosed; and man is gathering into his hands the laws of the very winds that toss its surface. ”

“ You are referring to the submarines, Toni, to the little submarines that were in existence at the beginning of the war—little grasshoppers of fragile steel that moved with great difficulty when on a level with the water and might be overwhelmed at the slightest shock.... But to-day there is something more: there is a submersible that is like a submarine protected by a ship's hull which is able to go hidden between the two waters and, at the same time, can navigate over the surface better than a torpedo-boat.... ”

“ But if we have no perfectly certain ideas regarding the propagation of the motions of the sea in depth, we can assert, that, whatever that extent and that power may be, the submarine currents no more abrade the rocks than rivers do the surface of the land. ”

“ When you press the stopper in, you compress the air in the submarine and force water in until the submarine weighs more than an equal volume of water and it sinks. When you release the pressure on the stopper, the compressed air forces the water out until the submarine becomes lighter than an equal volume of water and it rises. The water rushing out through the opening exerts pressure backward on the water in the bottle and the reaction drives the submarine forward. ”

“ A PEACEFUL SUBMARINE
Under the green sea, in the total darkness of the great depths and the yellowish-green of the shallows of the oceans, with the seaweeds waving their fronds about their barnacle-encrusted timbers and the creatures of the deep playing in and about the decks and rotted rigging, lie hundreds of wrecks. Many a splendid ship with a valuable cargo has gone down off a dangerous coast; many a hoard of gold or silver, gathered with infinite pains from the far corners of the earth, lies intact in decaying strong boxes on the bottom of the sea. ”

“ In the early part of this chapter I told you that the word submarine means anything that lives in, is done, or works beneath the water-line of the sea. Now, in naval engineering, submarine has come to mean an undersea craft that can dive, while an undersea boat that simply sinks on an even keel is called a submersible. So the Lake shown in Fig. 8 is a submersible, for it is not intended to dive. ”

“ Method of Submergence It may sound ridiculous, in face of the many accidents which have occurred, to say that one of the greatest difficulties is to make a submarine sink sufficiently quickly, and one of the easiest of operations to make her rise, and yet such is undeniably the case. ”

“ It is then actually displacing more than its own weight of water, for if left to itself it will rise rapidly and it is only the speed and the action of the rudders which keep it under. We see, then, that the action of a submarine in submerging itself is a real genuine dive. ”

“ The submarine quickly sank below the surface, aided by the deflecting rudder.
But alas for the hopes of the gold-seekers. No sooner was she completely submerged, with the engine started so as to send her out of the lagoon and to the open sea, than the waters all about were made brilliant by the phosphorescent phenomenon. In southern waters this frequently occurs. Millions of tiny creatures, which, it is said, swarm in the warm currents, give an appearance of fire to the ocean, and any object moving through it can plainly be seen. It was so with the Advance. ”

“ Surge after surge pounds savagely on the great rocks of the reef, and finally a mighty wave that seems to be a giant effort of the madly tortured sea lifts a raging crest high up, and drops it in the roaring surf. A great rock splits beneath the blow, the wave runs up the tall thin shaft and dashes high above its top, and then drops swiftly down, while there, unharmed amid the vastness and the terror of the storm still stands the tower that puny man has built to warn ships from the dangers that surround it. ”

“ The various motions man obtains by means of ponderous machinery are here vested in this simple, almost structureless animal, which has aptly been likened to a drop of animated sea water, and the facility with which it rises to the surface or descends to any depth might furnish hints towards the solution of the submarine vessel, which is at present so engrossing the attention of naval authorities the world over. ”

“ They also hear the rumbling noise of every nodule and fragment of rock, which are continually rolling upon the submarine stratum; which altogether make a kind of thundering roar that would surprise and fearfully engage the attention of the curious stranger. ”

“ Now, the body of a man lying in the water flat on his back will float with little or no exertion. It would appear, therefore, that similar proportions would suit a vessel whose purpose was floating only. It is not necessary to suppose that the ark had to contend with either storm or wind. The waves of water lying to the depth of a few fathoms upon a submerged continent could not, at any rate, be compared in violence to those of the ocean. ”

“ Imagine yourself in a submarine that has ventured a few miles out of port, imagine that you have headache and nausea, and that some ship of the Cobra type is flashing itself and its search-lights about whenever you come up to the surface, and promptly tearing down on your descending bubbles with a ram, trailing perhaps a tail of grapples or a net as well. ”

“ But slowly—very slowly, yet surely—rises the long chain of islands by a double process; the submarine crust of the earth is cooling, and the rocks are folded up as it shrivels, while the molten material within, pressed out through the crevices, overflows and helps to build up the sea-defiant wall. ”

“ I thought it would be possible to remain submerged only a short time unless I provided some sort of apparatus to extract the carbonic acid gas and restore oxygen to the air after breathing and exhaling the air in an enclosed space like a submerged vessel. I took up the question with various physicians and with a professor of physiology at Johns Hopkins University, and, according to their information and text-books, it would be a very difficult matter to carry sufficient air to remain submerged without change of air except for a very short time. ”