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from both land and water to keep the crew in a healthy state and especially to combat the scurvy is apparent, while in case of disaster their humble abodes are always open to the shipwrecked sailor until there can be convenient times for retreat to reach more civilized succor—a retreat in which the white man may be greatly aided by the native method of transportation. A fire hole being dug in the ice near by which must be opened every morning and evening, and a snow house thrown over it, if natives are convenient, to protect it from drifting snow, and our ship is ready to pass her Arctic winter unmolested until the coming summer opens a renewal of her labors. Should the circumstances of the case warrant an early start in the season, it will probably be necessary to cut a very long channel through from six to ten feet of ice of sufficient dimensions in length and width to float the ship to the outer open water. This channel is generally constructed as shown in horizontal projection in the following figure.

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The channel B. B. B. B. is always brought up alongside the ship, as shown, since should she draw more water than the thickness of the ice, and the channel be brought up immediately under her, the outgoing tide or a strong wind might sweep her out before it was intended she should move. The scarf lines cc. cc., formed in sawing, are sufficiently intelligible to be understood without an explanation, the iceblocks a. a. a, being allowed to float out along with the ebbing tide, a single person directing each one as fast as sawed off to prevent its rotation and consequently binding in the channel. If the vessel delays her starting until after the solar rays have made considerable impression on the ice of the harbor, it will save much labor to remove the snow along the contemplated scarf-lines of the channel, and place thereon a covering of black seaweed, sand, dirt, or ashes which will have cut deeply into the ice by the time the sawing is necessary. These layers, of course, should be very thin, otherwise they will protect the

ice instead of acting as ready conductors of the sun's heat. A little funnel-shaped harbor with but few projections along its converging sides may sometimes be relieved of all its ice at one time by a small amount of sawing along these serrated edges and a happy combination of tide, wind, and good management. This is especially the case where the rise and fall of the tide exceeds the thickness of the ice, the consequent vertical oscillation of the ice keeping it broken up in hummocky masses along the shore line. The use of blasting apparatus has so far been of but little use, wherever used, still I think a series of small charges, fired electrically, giving rather a pushing than a concussive effect, might be used advantageously in removing quite large masses of obstructing ice. Blasting, I believe, would also be more efficacious in harbors not fed by fresh water streams, as here the ice is more brittle, less tenacious and elastic, and consequently harder to remove by the percussive power of explosives. The difficulty of sawing increases in a rapid ratio with the thickness of the floe, and when its depth becomes so great as to allow a play of but a foot or two with the ice-saws it becomes essentially impossible. Ice-saws if very thick impose severe labor on those operating them by their great weight; if thin, they will warp and cramp in the thick ice, also creating severe labor. As all these contingencies cannot be foreseen it is desirable to have quite an assortment of these utensils varying in length and weight. A sailing vessel can nearly wait until she is liberated by the forces of nature, as this will probably be the earliest date at which she can take advantage of the season owing to her peculiar motive power. While a vessel is certainly safer when in harbor, this position may not always be without its dangers. She may have entered such a haven during an exceptionally open season and unless this recurs within the limit of time allowed by the ship's provisions she must be abandoned to save the lives of the crew. Such was the experience of the Investigator, abandoned in 1854, in the Bay of Mercy, Bank Sand, by Mc Clure of the Royal Navy, while on a search for Sir John Franklin.

It would be a useless waste of time to go into the various advantages derived from employing two ships instead of one wherever the funds available will allow such a course. It proved the salvation of Parry on his third journey and other instances are not wanting. They should both be provided with equal motive power, steam or sails, in order to prevent separation. The use of balloons to make slight ascents—they being made fast to the ship-to enable the ice master to obtain a more

comprehensive view of the state of the ice, has never yet been experimented upon, though by many recommended, and consequently cannot be either rejected or accepted as an auxiliary in this sort of cruising. Certain it is, however, that nothing is more deceitful than ice packs or ice drifts at a distance, the most invulnerable looking, upon a closer examination, proving to be the most disjointed oftentimes, and the re

verse.

Although from this rather long list of probable Arctic accidents to which a ship is exposed escape would seem rare, yet after all it is wonderful the small number of craft actually lost in this dangerous species of navigation, in proportion to the whole number engaged.

The compass, that all important little guide in more favored zones, here becomes almost practically useless. In North Hudson's bay and strait, and, in general, near the magnetic pole, its sluggish oscillations are easily overcome by the most insignificant local attraction, which it is impossible to avoid upon shipboard. The farther removed from this great center of magnetic force, necessarily the more reliance can be placed on the needle. While in this district the direction may be approximately determined by a watch or chronometer rated to mean local time conjoined with the well known uniform motion in azimuth of the sun which, barring cloudy weather, will be continually in sight during the twenty four hours during the greater portion of the voyage. This direction will be sufficiently exact for a navigation which after all depends rather on the bearings of the "leads" and ice barriers than on any determinate points of the compass. The fact that a vessel should follow a continuity of land, as already described, lessens the value of this instrument while capes and headlands can be kept in view.

PRIZE ESSAY

1880.

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Rear-Adm. G. B. BALCH, U. S. N., in the chair.

The meeting having been called to order, the Cor. Secretary, Prof. C. E. Munroe, stated that he had received from the honorable Secretary of State, the eight essays forwarded to him in Jan. 1880, by Lieut. J. C. Soley, at that time Secretary of the Institute, together with the following letter:

"The undersigned to whom it was referred to examine the essays submitted in competition for the prize offered for the best, by the Naval Institute, having performed the duty with which they had the honor to be intrusted, award the prize to the essay identified by the motto, 'Sat cito, si sat bene.'

Washington, Feb. 10, 1881.

W. M. EVARTS,

Prof. Chas. E. Munroe,

Cor. Secretary U. S. Naval Institute,

Annapolis, Maryland."

R. W. THOMPSON,
J. R. Mc PHERSON.

Prof. Munroe further stated that the Executive Committee had resolved to postpone discussion upon the Prize Essay until it had been printed and distributed, and upon his motion the thanks of the Institute were tendered the gentlemen who had so kindly acted as judges. The envelope bearing the motto designated was then opened, and the name of the successful competitor announced.

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