THE SUBMARINE BOAT.

Evening Star, Issue 3099, 24 January 1873, Page 3

THE SUBMARINE BOAT.

It has been already stated that tho diving boat, composed entirely of iron, floats by means of the compressed air contained in the reservoir at each end, aided by the air in the central chamber. If that compressed air is sti 1 further diminished in bulk, after the hold has been made safe and r-tight, it is clear that the specific gravity of th j . whole machine will be altered till it sinks. Accordingly into these air reservoirs the imprisoned men inject water by menus of a forcing pump, until they have thus taken in as much additional ballast as suffices to gink them. It is the principle of ballooning applied to the ocean instead of the atmosphere. Dr Payerne obligingly pointed out that they were pumping away, or loading the boat with warer, first at the tail of the vessel; which, in consequence, gradually sunk, till it scarcely floated above the surface of the sea. Then the front portion was similarly loaded, and became submerged ; and then—it was quite as exciting as the first sight of a bal oon ascent ; it was more fearful than seeing the kraken plunge into the depth below, after you had mistaken it for an island—down went tbe scar : et-mailed monster with a decisive dip which had all the air of a voluntary and muscular action. And the boiling waters, and the white streaming mass of bu' bling air, which those desperadoes left behind them on the surface ! Oh ! Gracious Heavens ! Can I believe my eyes?—that there, down below, and out of sight,—nine living, breathing men, should be cheerfully at work ;—though hidden from our view by the waves of the sea ! and not exactly hidden-only ve led Tho ■waters here are clear, their bed being of rock; and I can perceive a reddish gleam, with a brighter point in the middle, which is the point of the potence, struggling through the blue-green medium in which those nine wretched lost men lie entombed. Survive they cannot—short of miracle ! Lucky that none of their wives or child[on were here to witness that fearful descent. Full fathom five thy father lies: Of his bones are coral made ; Those are pearls that were his eyes. The “father,” however, quotes responsively, but for the miracle, I mean our preservation, few in millions Can speak like us.

The men are safe, thanks to Payerne’s in gsnuity. They have much more air with them than they will require during their stay below; they can regulate «the supply at pleasure, and this will give them sufficient oxygen. But, by.breathing, they throw off carbonic acid, and this must be got rid of, or they will suffer inconvenience, and, perhaps, bq injured in health. They, therefore. take down with them a bucket containing about six (French) pounds of firstrate quicklime, with a small portion of potash ; it is mixed with water, and, as aorni as their feelings tell them what is wanted to he done, one of the number takes a pair of bellows, having the rosj of a gaid'-n water-ing-pot fixed on its snout, and with this simple implement dipped into the alkaline solution, he blows away, until 1 be air is sufficiently purified by the passa e through it, to be aga : h wholesome to the lungs. For those who doubt the healthiness of housewashings, here is a lesson that the human body throws off a something, whoso ill effects are neutralised Ity lime. Dr Payerne has made many experiments on the purification of air—some, in th-f diving bell at the London Polytechnic Exhibition, ten years ago—and has published on the subject. Pht the diving ho it has led to the discovery of an unexpected means of clearing air of an excess of carbolic acid. 4 The bell cannot he worked in a strong current; the boat works best there, for this reason. It is known that carbonic acid is very soluble in water—much more soluble than atmospheric air; that is. it is taken up by it in cdmbinatmn, like sugar or salt, or, as they are both fluids, it might be better to say that water and • carbonic acid unite together like spirits and water, instead of remaining separate, like water and oil. Now it turns out that carbonic aciircmibines so readily with water that when the diving boat is working in a strong current, the men have no need to use their lime solution, nor to Work their bellows at s 'all. The water running beneath their feet attracts and carries off with it the carbonic acid as fast as they produce it; and, fortunately, carbonic acid is so much heavier than atmospheric air, that it naturally sinks to the bottom of the boat by its own weight. It is only in still waters that they aie obliged to hare recourse to the bellows and the alkaline air-filter ; and the more the water changes from the condition of stillness, the leas need have they of that acid. We may hence deduce the fact that fountains and running streams in the midst of populous cities are not only pleasing to the eye, but are healthful to the constitution, by carrying off, while they seem to be only idly sparkling to and fro, many an unseen, impalpable, and unsuspected impurity. Another difficulty with the diving-bell is, that the deeper it descends, the higher the water rises within it, from the compression of the included air by the superincumbent mass of water ; so that the adventurer finds himself half-flooded and seriously hindered both in investigation and in work, long before a depth impossible for human lungs to bear has been reached But the diving-boat, by making use of the internal spring of its store of compressed air, is always able (by letting out an extra supply as profounder depths are arrived %t) to keep the water-surface quite at tho bottom of the internal ‘walls of its chaste It at fort light, a little

paradoxical to learn that it costs much less trouble to make the Auguste float on the surface, than to cause her to sink to the bottom of the sea. But a very slight change of equilibrium or alteration of sp cilic gravity is sufficient to produce the tendency to float. If you sink a bladder full of air in a tub, by means of a small bag-full of snot just enough to keep it at the bottom, it is surprising how few shot Slave to be subtracted, in order to make it mount; just as, in a nicely balanced balloon, the shaking out of a small sand-bag causes it to mount steadily. And so the Auguste, by discharging a little water through the spiracles of its iron shefl, makes itself lighter, and rises buoyantly. The idea is beautifully simple, and would be perfectly novel if similar contrivances had not been observable in the structure of cm tain marine animals. Human ingenuity has sometimes the good fortune to hit upon means similar to those employed by the threat Author of Nature ; ami is then most sure, as well as most successful. The descent of the Auguste, on the other hand, is effected by a laborious injection of water into the reservoirs of compressed air ; and, of course, the greater the store of breathable provision, the harder work it is to cram and force upon it so unyielding an intruder as water is—(he squeczeable of thing'. The air docs yield at last to the impudent invasion, but with a very bad grace, and after proving itself to be somewhat heated by the contest. Moreover, for convenience sake, a greater excess of floating power is usually maintained at the surface, when the Auguste lies at her moorings, than of sinking pow r at the bottom, when she wants to lie steady at her work.

It is good for the safety of the crew, that this should be the case—namely, that it should be less trouble to float the Bateau PJongcur than to sink her. But Dr Pay< me has superaddod a very boantifd and simple contrivance, by which, if the pumps should fail to perform their duty, the Bateau can, by a few touches, be insta t'y brought to the surface. It is a proof, too, how little complex the whole management of the machinery is, that the workmen who dive conduct it with perfect confidence, and, Dr Payerue says, quite as well as himself We left the men at the bottom the Sea The master had returned to his scientific labors, and I had gone home to put on paper something of what I had seen and heard. Having been present at tho imprisonment of the nine martys, I was anxious to assist, as the French say, at their escape. They went down at nine in the morning (<>r a little after, for my visit caus' d a short delay), and they wore to emerge about one in the afto nonn. I returned at the time appointed, and was just too late to see the Augu te r se, like a\ emus with the scarlet fever, from tho sea ; but the living cargo was untouched and unadulterated : the tenth man was beginning to uutackle the trap-door, and clear the rop a from the pulley and gibbet. At last, the ho e opened (it just comes into my head that it is very like the hole in a humming-top, which admits the wind and causes tho music ; or, still more like the enjarged bung-hole of a cask, —and one by one they lifted themselves out. There was no struggling or lighting who should get away firstly, as must have, been the case had they been pent up for four hours in a real and true “ black-hole of Calcutta the exit was made quietly, and even a little lazily. The first word which I hoard from their mouths was not—“'J hank God, here we are, above water again ! ’ nor—- “ Catch me at the bottom another time, if you can 1” but the foreman, turning towards the dock wall, on which we were standing, asked fi Somnss noun him descendus! ’ “ Did we make a good descent?” Think of the fellow’s coolness in caring about ttie style of the performance ! I almost be ieve that he purposely made the last plunge a little more precipitately than usual, simply to show what a high-mottled Triton his Auguste could be on occasion.

The other men toddled off to their dressingroom, not a bit more beaten than minors whom I have seen returning from their work. To say that they were as cool as cucumber*, and as neat as if they came out of a bandbox, would nob be trnp. But they -were to get a hasty snack of dinner, and go down again in the afeernorn. The air reservoirs contained sufficient for that day’s consumption, without any more being pnmpo 1 into them. Next morning, a fresh stock would have to be laid in. Eight houia, divided into two spells, is the usual day’s work at the bottom of the sea; hut, sometimes, when the boat drops nicely, in a convenient position, a shorter stay enables them to satisfy themselves and others as to the quantity of rock removed. The fragments detached are brought up in the diving-boat. These things are only the beginnings of wonders. What Dr Payerne longs for, is additional mechanical power to work his invention, which he feels certa’n of gaining when he has obtained additional capital. He proposes to make a submarine steamboat, which, however, the reader may stare, is as actual a possibility as the Auguste is an existing fact. But, expense is the present stumbling block ; experiments cannot be made for nothing, Tho submarine steamer would have two tires, one for the surface, and another for tho deops. Up above, it wonkl burn air i hut air is -too valuable to hum in the abyss below. Heat must thm bo gen: rated by means of nitrate of potash, though the process is much more costly. Ttye first descent was made in the Seine at Pars ; and it showed the confidence iVhich the inventor placed in his apparatus. Inclosed in an iron cage at tha bottom of a river, he could not have been very easily raised to the surface, either dead or alive, if the effect calculated on had not been produced by the means emp’oyed. But, a trial in the sea at the time of high water, and at a point above low water mark, would have insured him some sort of succour in case of need, if ho patiently waited in his den for three or four hours, and had only air enough to breathe. The greatest depth to which Dr Payerne has yet descended, is seventyfive French feet—a trifle more than Knglish, Bn 1- , many va liable cargoes lie sunken deeper than that, and are well worth the fetching up again. He believes that a man is capable of sustaining the pressure resulting from a depth of a hundred and fifty feet; but, to attain that result, he would require to use steam engines as his air compressors. Manual labour is incapable of the effort; and he has not at present sufficient pecuniary means at command to mak« the necessary outlay. Whether the invention is to halt where it is, or progressively to grow into tho marvel of a submarine locomotive steamer, the name of jthe man who has already dared and performed so much, ought to be enrobed on the list of the world's notables. And. therefore, I venture to propose that the words—Diving Boat—or Bateau Plougeur, be now for the last time used in England, and that henceforth, when we wish to mention this admirable result of mechanical skill, we call it simply— A PAYERNE.