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floated across the Atlantic at the rate of about four miles a-day. An iceberg in the same situation would have coasted Labrador, crossed the tail of the gulph stream and the bank of Newfoundland, being carried southerly by the under current, whereas the bottle floated easterly by the superficial movement of the water.
There can be little doubt that the great quantity of field ice and the multitude of those icebergs which, from gales of wind or some other cause, were dislodged from their abodes in Baffin's Bay and the Greenland seas in the winter and spring of 1817, and carried into the Atlantic, were the main cause of the extreme chilliness and dampness of the weather on the coast of America, and over the eastern coasts of Europe in the summer of that year, and that the almost total absence of ice in 1818 produced that warmth and dryness felt through the winter, not only by us and all the northern parts of Europe, but also along the whole coast of America. In the depth of last winter, the Baltic remained unfrozen; so late as the end of February the bays of Newfoundland were free from ice; and even to the middle of April there had been neither ice nor snow on Iceland, a circumstance which had not happened before in the memory of man. The fact may probably be accounted for by the long continuance of southerly winds, which, as found by both the late expeditions, had hemmed up the ice to the northward; and so likely is this, that the Greenland fishermen have a common observation that when the winter at home is mild, they are sure to meet with a close season in the Arctic seas. That the approach to the southward and the melting of such masses of ice should exert an influence on the temperature and movement of the atmosphere is no new idea; and the dissolution of an ice-mountain of the following dimensions, measured by Mr. Parry, must be allowed very materially to disturb the equilibrium of the atmosphere. It was more than two miles square and 367 feet high: its weight by measurement was 1,292,397,673 tons—and it was capable, if reduced to a plane of a foot in thickness, of covering a space equal to 1750 square miles.
Having thus fairly stated our objections to the conduct of the voyage, we shall just glance at the advantages which have resulted from it. In the first place, we are now quite sure that there is such a bay, or rather inland sea, as that of Baffin, though neither so wide nor of the same form as it is usually represented in charts. One chart, however, must be excepted, which is that of the navigator who quaintly calls himself, ' the North-west Foxe.' The coincidence of the latitudes and longitudes, but more especially of the latter, with those observed by Captain Ross, is so very *triking (being within a degree of longitude on both sides, or fifteen teen miles) as to lead to the conclusion that Foxe must have been in possession of Baffin's chart, which Purchas found too troublesome and expensive to engrave. All the other charts that we have seen are very far wide of the truth.
In the second place, the swinging of the pendulum on Hare Island in lat. 70° 26' has given results, we understand, highly satisfactory, as tending to corroborate the previous theory for determining the precise figure of the earth, built on experiments made in various latitudes, but never before in one so high as this.
In the third place, the variation and dip of the magnetic needle, and the intensity of the magnetic force taken at different places so very near to one of the magnetic poles, are, in themselves, exceedingly curious, and may lead to important conclusions. It had been foreseen that the probable approach of the ships to one of the magnetic poles would afford the opportunity of making some interesting observations, and accordingly compasses of various construction, and other instruments, Were provided for this purpose. We cannot find, however, that they have been used to the extent which would be desirable.
Another phenomenon, connected with these observations, seems, however, to have attracted the marked and continued attention of our navigators. It had been noticed, on Captain Cook's voyages, that the variation of the magnetic needle differed very sensibly on the same spot with the different directions of the ship's head, but not to such extent as to be considered of much importance to navigation. Captain Flinders, however, resumed the subject, and made a series of observations both on his voyage of discovery, and after his return to England, from the result of which he constructed a formula for correcting the error of the ship's course as steered by the compass. This formula, however, was found to be wholly inapplicable in high latitudes, where the deviation of the needle from the correct variation was much more considerable than where Captain Flinders had an opportunity of making his observations. He concluded, justly enough, that the error was occasioned by the iron in the ship; but conceived that the attractive power of it was concentrated in some particular part of the ship, whose influence was exerted on that pole of the needle which dipped towards the pole of the earth, and was drawn aside towards it. The fact, however, as might have been supposed, is, that the compasses of different ships are differently affected, according to the quantity and the disposition of the iron employed in the construction of the vessel, or of her ballast, guns, 8tc. and consequently, that each ship will have her particular deviation,
Vol. xxi. No. Xli. E which which will differ very materially in different parts; and the points of one ship's head, which give no deviation, will, probably, in another, be those of the greatest deviation. These irregularities must, no doubt, be owing to the unequal distribution of the iron with regard to the two sides of the ship. This was remarkably the case on the present occasion, the compasses of the Isabella differing from those of the Alexander not merely several degrees, but in some situations several points; in fact, in the high latitudes where the dip and variation were greatest, so sluggishly did the needles act, that those which were loaded with heavy cards would scarcely move at all, but stood still at any point to which they were directed. In middle and low latitudes this deviation is of little or no importance, and in high latitudes we suspect it can only be truly ascertained by actual observations frequently repeated. Dr. Young, however, has constructed a formula and a table from the experiments of the Isabella, which may assist, at least, in coming to an approximation of the deviation. The following results of the mean of several observations taken on the ice, for determining the variation and dip of the magnetic needle, may be considered as approaching nearly to the truth.
A series of observations on the temperature of the sea at the surface, and at certain depths, may serve to correct erroneous notions, which, it would appear, have prevailed on this subject. We have no doubt they are the most accurate that have yet been made, afid in deeper water than a self-registering thermometer had ever been sent down before in any part of the world. The result is very different from that of former observations. It seems that, in Baffin'sBay, the temperature, generally speaking, decreases with the depth. At 1005 fathoms, in lat. 71° 24', the temperature was8|°,
at the surface 36*, and whenever the depth exceeded lOOfattioms, the thermometer generally descended to 30°, or below, when 31 or 35 at the surface. Near Cape Walsingham, it is stated that, from the depth of 660 fathoms the thermometer came up at 2.0 J; from 400, at 28°; from 200, at 29°; and from 100, at 30°: the temperature of the air being 37°- It would be difficult to explain why the sea remained in the state of water at 25^° of Fahren. heit. Did the pressure of the column of water prevent its freezmg ?—or was the water more strongly impregnated with salt I These and other observations made in the course of this voyage, both on land and sea, are completely at variance with the theory of isothermal lines of temperature which had been assumed, as it would now appear, from a too limited number of facts. But the most unaccountable circumstance is that of the Polar Expedition having, in the seas of Spitzbergen, on the same parallels of latitude, invariably obtained a contrary result, the temperature of the sea increasing with the depth; so that when the thermometer at the surface stood at 32° or 33°, at 300 fathoms it was 36* or 57^. We pretend not to explain this singular anomaly ; indeed we do not conceive that we are yet in possession of a sufficient number of facts to enable us to reason on the subject.
A remarkable uniformity of temperature prevailed throughout the three months the ships were within the Arctic circle. During the whole of this time, the mercury in Fahrenheit's thermometer (in the shade) never ascended beyond 53°, nor fell below 26i°; and these extremes occurred but once, the general average being between 35° and 37°. The consequence of which, and of keeping the ship dry, was, that no deaths took place, and scarcely a clay's illness in either vessel; and Mr. Parry, judging from these circumstances, says, 'I have not the smallest doubt that a shipi provided, as we were, with abundance of provisions, warni clothing and fuel, might winter in the highest latitude that we have been in, without suffering materially, either from cold or disease.' When we reflect on the wintering of William Barentz and his companions in 76° of latitude in the coldest country on the face of the earth, destitute of all these advantages, we can scarcely doubt that Mr. Parry is right
So long as the sun was perpetually above the horizon, there could not be any appearance of the aurora borealis. This phenomenon commenced, however, with the commencement of night, and was frequent on the return voyage. In a tremendous gale off Cape Farewell, these lights played with awful magnificence. The Isabella was furnished with an electrical apparatus, contrived by Sir Humphry Davy, but it does not appear to have been used. Mr. Parry paid particular attention to the compasses dull 2 ring ring the appearance of the aurora, but could not perceive that it bad the slightest influence on the magnetical needle, either in altering its direction or causing any tremulous motion; he observed however that the arc was generally, though not invariably, intersected by the magnetic meridian.
Where nature has been so sparing in the number and variety of her gifts, much could not be expected from the expedition, especially as no professed naturalist was employed on the occasion: the few opportunities which occurred for collecting specimens were not, however, neglected. On this subject, Captain Ross complains of the unwillingness of Captain Sabine to assist him, which he certainly ought to have done, though not engaged specifically for that purpose. It is a great misfortune for the interests of science, that commanders of ships of war and naturalists rarely agree; but it arises generally from the objects of their several pursuits interfering with each other. Captam Cook indeed agreed with every one; but Vancouver and Menzies quarrelled. Boudin was at variance with all the savans on board; but this was the less to be wondered at, as they were almost numerous enough to man the ship: and Captain Freycinet, who is now employed in the southern hemisphere in astronomical, magnetical, and meteorological observations, positively refused to take on board a single naturalist.*
We observe with pleasure that in consequence of the Prince Regent's Order in Council, grounded on the late amended Act of Parliament, the Board of Longitude has adopted a graduated scale of rewards for discovery, proportioned to the progress made to the westward, from Hudson's or Baffin's Bays towards the Pacific Ocean: as certain portions of these rewards are allotted to places not very remote from the usual haunts of whale fishers, such as have not been fortunate in the fishery may be induced to strive for them, through Cumberland or Lancaster's Straits, or some other of the numerous openings in the western land. It is possible indeed that the first point of the scale, the meridian of the Copper Mine River of Hearne, (which entitles to 5,000/.) may turn out to be much nearer to Davis's Strait than it appears to be on the charts. Mr. Hearne, by his own account, made but one single observation for the latitude, and that at a considerable distance from the mouth of the river, so that whether its latitude be 69° or
* To be even with the Captain, the Minister of Marine interdicted all females from proceeding on the voyage, knowing that Freycinet had intended to take his wife with him. On the third day after the ship's departure from Toulon, a youth made his appearance on the quarter-deck whom the commander had not before observed—it was hti wife, whr, in the disg'iise of a seaman, had got on board just as the ship was weighing anchor, and concealed herself among the crew.