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NEW YORK BRANCH.

DECEMBER 27, 1880.

Captain H. A. BARTLETT, U. S. M. C. in the chair.

ICE NAVIGATION,

By LIEUT. FREDERICK SCHWATKA, U. S. A.

This subject, embracing in its whole extent the construction of ships —or altering of those that have seen less severe service.—for this pe. culiar employment, their management and direction under the various combinations of ice-packs, ice-floes, icebergs, tides, storms, currents, and other obstacles, when they have entered their frigid field of action, their care and preservation when securely anchored by the cold clutches of the ice, for the long dreary winter night of the Arctic, their liberation when the summer's sun has broken up the great ice fields, and their reënactment in inverse order of their former experience, as they prosecute their journey or return home, as will be more likely in the light of past Arctic adventures, can all be more fairly comprehended by following the history of such a vessel through all the above until its return to its native waters, or its crushing amidst the grinding pack or its final abandonment by a long beleaguered crew to the unyielding fetters of the frozen zone ; to follow it from its launching back to its lucky laurels or from its dock-yard to its doom.

I will not dwell upon such indubitable facts as the quality of the ship's material, which it is evident must be of the very best, be it wood or iron, or, the almost equally apparent fact of the superiority of a vessel specially constructed for this purpose, in the hands of proper persons, who have had experience in Arctic navigation as well as naval construction over the reconstructed merchantmen or even stronger built man-of-war.

Nothing is more favorable to ice-navigation than a propitious season, and the history of the Arctic is replete with instances where different explorers, at different times, have found the most startling variations in the state of the ice, in the same locality, and at the same corresponding time of the year. So well is this fact appreciated by experienced navigators of these waters that you will seldom find one give that credit to Arctic success which is so often so fully accorded by the press and the public. Rightly estimating that it was not altogether superior management over his more unfortunate brethren, but largely due to the fortunate circumstance of a lucky season, which is a problem defying calculation. Lieutenant Payer of the Austro-Hungarian expedition has pointedly said: “The commander of an expedition must possess sufficient self-control to return as soon as he becomes convinced of the existence of conditions unfavorable for navigation. It is better to repeat the same attempt on a second or even a third summer, than with conscious impotence to fight against the supremacy of the ice.” Splendid as this maxim appears upon the face of it, it nevertheless has the weak point that it is based on things as they should be, rather than on things as they are, and should any Arctic commander, actuated by honorable motives, adopt such a course, he would probably find this maxim, when he returns home, exchanged for that one of Napoleon that “there is nothing so successful as success”; and should the same attempt be repeated on a second or third year it is more than doubtful whether he would find himself retaining his orignal position. It is often this unfortunate relation existing between an ambitious commander and his inexperienced countrymen at home that has done so much to add to that huge list of rotting hulks and human bones which form a necklace of honor around that pole they could not reach. But let us return to our ship and determine in the scales of experience of what material she shall be made. These tell us that the superiority of iron ships over those of wood no longer holds in the Arctic. The rapid conductive power of the former makes it almost impossible to keep an equable temperature in any portion with out a thick inside coating of some non-conductor, besides the more rapid formation of frosts from condensed moistures along the outer sides of the bunks, causing serious diseases, and greatly aiding the propagation of that most terrible of all Arctic scourges, the scurvy. The superior strength and endurance of iron over wood in the usual accidents of the temperate and tropical seas seem to be lost when the test comes in the shape of severe pressure from the ice, the elasticity of the wood allowing it to return to its original shape after an almost indefinite number of nippings which are not sufficient to directly crush the vessel, while the same number of equal pressures in its iron Companion become slowly accumulative, until it finally succumbs. A wooden vessel, however, may be very properly plated with iron over the hull, for some feet under the water, to protect it from the grinding action of the “ice tongues,” which are formed by the unequal melting of the edges of large ice cakes, and projecting their huge submerged points, often for a distance of twenty or thirty feet, become dangerous to a vessel compelled to thread narrow and tortuous channels and “ leads” in an open field of pack-ice, where the first intimation of their presence is a low, dull, groaning sound, and a Swinging of the ship, probably a half a dozen points of the compass, despite the helmsman, or probably a perfect arrest as the helpless ship comes up broadside on against the cake of ice, and with all sails thrown aback, if that be her motive power. Theoretically, therefore, iron ships are inferior to their weaker but more elastic wooden compeers, and this theory is ably demonstrated by facts in the sad fates of the River Tay in 1868, in Baffin's Bay, and of the Swedish exploring ship Sophia in the north of Spitzbergen ; in both instances these vessels sank under circumstances where good wooden vessels would have survived. Having decided to build a wooden vessel the shape of the hull is not a matter altogether of perfect indifference. The full round ship, Or, nautically speaking, a ship with full lines is much more liable to be crushed by ice-pressure than one built with sharp lines, as fully illustrated in Koldewey's German expedition when the Germania, built upon the latter principle, stood the ice-hip without very serious consequences during a heavy storm, while her companion the Hansa was crushed and sunk, she being modelled upon the former plan, and this despite the fact that the Germania was the larger vessel and therefore more liable to destruction than her lighter escort. This last statement would bring us to a consideration of a proper size for an Arctic exploring ship, and while this may vary through tolerably wide limits, depending upon the equally diverse objects to which she may be put and the time she is to be employed in icy seas, still the general principle that a vessel should be as Small as possible, compatible with the Object in View, is a good one. The smaller and lighter the boat the easier she is to raise by the squeezing floes; and this lifting of a vessel from the glacial vice, in some cases completely from her element has been the salvation of many an ice beleaguered boat. The superiority that a large vessel has over a smaller one in its greater momentum, when called upon to “ram” the ice, so as to force a passage, is compensated by the fact, which experience has fully corroborated, that the large ship will succumb sooner to these severe and repeated shocks that she is thus compelled to bear. It should be added that it is only when the floes are small, and the ice comparatively loose, that any ship, whatever may be her size, can ram it with any fair prospect of effecting a passage through. Again a small ship is more readily handled in the tortuous channels through which she is often compelled to thread her way while working in floes sufficiently open to just allow progress. While all Arctic authorities agree upon the employment of small ships, the exact size in tons is seldom stated, but in the few cases mentioned about four hundred tons may be taken as the maximum limit. The charging, ramming, or pushing of ice, by a vessel, brings us to the consideration of the motive power most serviceable for ice navigation—steam or sails alone—for it is only by the former that charging can be made possible, except in these extremely attenuated packs where the headway of the sailing craft is sufficient to carry her safely through, but it must be added that such packs are seldom encountered. The use of steam may be laid down as a positive rule to be all important, despite the fact some few persons of no inconsiderable experience as Arctic navigators still denounce the waste of room occupied by the steaming machinery, its necessary fuel for so long a journey, and the almost triple anxiety imposed upon the commander regarding his propeller, which is constantly breaking its blades despite its protector of iron grating, and other derangements of machinery that may here become extremely difficult if not impossible of repair. The first attempt to use steam power in the frigid zone was essayed by Sir John Ross in the Victory, a small vessel of but eighty-five tons, which sailed from England in 1829, carrying sufficient coal for one thousand hours steaming. At that time the screw-propeller was unknown, and the Victory was fitted up with paddle-Wheels, which proved so utterly worthless in the very first ice they met, which, added to an unfortunate accident which permanently disabled the engineer, and the constant attention the new machinery required, finally forced Ross to fall back wholly upon his sailing power, with which he continued his journey, at last abandoning the Victory in Prince Regent's inlet, the first he had lost of thirty-six vessels that he had commanded during forty-two years' service. This complete failure of the paddlewheel in ice-packs, however slight, fittingly fixed their doom forever. The first use of the screw-propeller was on Sir John Franklin's illfated expedition in the Erebus and Terror in 1845. How effectually they worked, like all other information concerning that party, is Wrapped in mystery. Certain it is Sir John Franklin came nearer accomplishing his object than any of his predecessors, but whether due to his propellers or to a favorable season can only rest on conjecture ; suffice to say they were certainly not powerful enough to release him from his two years' besettal in the ice-packs of Victoria strait, unless the cause was due to a scarcity of coal. With the various improvements in propellers, especially in their protection and other adaptation to this peculiar service, came their more universal use in Arctic navigation ; and at this date one seldom hears of an expedition to these regions not thoroughly fitted with this most essential auxiliary to a perfect success. By steam power only can a vessel defy the ever variable winds of those regions. Running before a breeze and with a current in the same direction is the most favorable condition that can be secured for a sailing craft, not on account of speed which is thus facilitated (for a vessel in the ice should under no circumstances, be she steamer or sailer, exceed six or seven knots per hour, while three or four is not a bad average to adopt), but on account of the disjointed and open condition of the ice-pack that is produced by this state of affairs. Even in this most favorable state, if she be running towards the narrow portion of a funnel-shaped channel, she will more than probably encounter a gorged ice-pack at this point barring her further progress. A sailer caught in this predicament is in a very precarious condition. To attempt to return against both wind and current is sufficiently hard, as all sailors know, but when there is added to all this the incoming pack-ice, which will certainly add two to three and often four or five points to her lee-Way, in constantly attempting to weather the large ice-cakes and often equally dense and larger ice-packs with fruitless results, the time lost in Wearing her around or throwing her on the other tack when a channel open one minute has closed in her front, makes it almost if not quite impossible to return, and the grinding, crushing pack soon builds up to her position and encloses her under the most dangerous circumstances that can occur in ice-pressure, unless she can find an “ice dock”. like that described by Dr. Kane, and even this, at any minute, is liable to be obliterated by an increase of wind or a pressure due to the acCumulation of ice or change of tide. This state of affairs is, I think, more than probable, illustrated in the case of the besettal of Sir John Franklin's expedition, the Erebus and Terror, in September, 1846, off Cape Felix of King William's Land. Attempting to pass through Victoria Channel, whose southward trending current is at this point

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