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attempts by the English and the Dutch on the one side, and by the Russians on the other, go far to prove the utter impracticability of a navigable passage round the northern extremity of Asia; though the whole of this coast, with the exception, perhaps, of a single point, has been navigated in several detached parts and at different times.

But the question of a north-west passage, which would be much shorter, and of a polar one, which would be the shortest of all, rests on very different grounds. That the north pole may be approached by sea, has been an opinion entertained both by experienced navigators and by men eminent for their learning and science; that several ships have at different times been carried three or four degrees beyond Spitzbergen and the usual limits of the whale fishery, is not merely a matter of opinion; and if the polar sea be navigable to the height of 84°, there seems to be no other physical obstruction, than the intervention of land, to the practical navigation of that sea to the north pole itself; as there is no reason to suppose that the temperature of that point is lower in the winter, while it is probably much higher in the summer, than on the parallel of 80°; as it is well known that the latitude of 80° is generally not colder on the same meridian, and in many places much less severe, than that of 70° is in others. The Russians

the winter very well on Spitzbergen, but they have not ventured to winter on Nova Zembla many degrees to the southward of it. Deer live and thrive in 80° latitude on Spitzbergen, but cannot live in 75o on Nova Zembla. Neither does the quantity of ice, whether formed on the surface of the main ocean, or floated out of the bays and rivers and from the coasts, depend on the degree of latitude where it is found. Ships, for instance, navigate freely every year round the North Cape in the parallel of 72° or 73°, and proceed along the coast of Spitzbergen without impediment from ice as high up as 80°, while on the opposite coast of America the sea is not navigable at all for a great part of the year from 45° upwards; and the parallel of 66° forms at present the utmost limits of northern navigation on that coast.

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It is a well established fact that the cold is much more intense on the eastern than on the western coasts of continents and islands. Iceland furnishes a curious instance of this fact; the whole eastern coast being a series of mountains covered with ice and snow, and immense glaciers, moving downwards to the very sea; while the mountains and the fiords or firths on the western side are generally, if not always, free from ice;-but what is still more extraordinary, the opposite coast of Greenland in the same parallel of latitude and four degrees to the southward of it, and at the short distance of one hundred and fifty miles, is guarded from all approach by a perpetual and interminable barrier of ice.

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In fact the ice-bergs and those vast fields of ice which float about on the sea, and are wafted down by currents into the Atlantic, are chiefly formed on coasts and in bays, in narrow straits and at the mouths of great rivers. The whole coast of Siberia is a fertile source of this supply. The multitude of large rivers which fall into the polar sea, by carrying down alluvial earth, have formed numerous expansive and shallow bays of fresh water, which, in the course of the winter, become so many solid masses of ice.

solid masses of ice. As the sources of these rivers and a great part of their course are in more southern latitudes, where they never freeze, the water they supply is, in the winter, dammed up near the mouth, and ice-bergs are formed, which, when broken loose, are drifted out to sea. In the same manner the field ice is formed in the straits and bays and on shallow coasts, which, when set afloat in the spring, is carried out into the sea; in this situation it is drifted about till heaped piece on piece, and driven about, it again fixes itself among archipelagos of islands, on shallow coasts, and in straits, bays and inlets, where each field becomes a nucleus for an increased accumulation-as in the straits of Bellisle and Behring, for instance, and in every part of Hudson's Bay, down to the latitude of 50°. One vast chain of field ice is usually found wedged in between the eastern coast of Greenland and Spitzbergen, in the direction of northeast and south-west, which, as the summer advances, and particularly when the wind blows from the northward, opens in various places; and when ships have passed through these openings to the northward they have generally found the sea clear of ice.

If therefore the great polar basin should be free of land, the probability is, that it will also be free of ice. It was the opinion of Frobisher, Davis, and most of the old and experienced navigators, that the deep blue sea does not freeze. This would be to assume too much, as its surface has frequently been observed to freeze when not agitated by the wind; but it may be doubted whether a deep and extensive sea can be permanently shut up with ice. The almost perpetual agitation of the surface, and the increased temperature of the water at great depths, and consequently its diminished specific gravity, which will cause it to ascend, will probably prevent those immense fields and masses of ice from forming, which are met with near the land even in very .

low latitudes. It was, at any rate, desirable to ascertain how the fact stood in this respect, and whether it was practicable to reach the north pole,-in which case, there was no reason to doubt that it would also be practicable to proceed by that nearest route to Behring's Strait. The only expedition which had hitherto been sent out for the express purpose of advancing towards the north pole, was that under the command of Cap

tain Phipps; but the two vessels employed on this service having unfortunately got hampered and entangled in the shallow sea and among the islands on the northern and north-eastern side of Spitzbergen, at an advanced period of the season, it returned without making any discovery.

The case is different with regard to the northwest passage. From the very frequent attempts which have been made for its discovery, it is now known pretty nearly whereabouts such a passage, if it exists at all, must be looked for. It has, for instance, been ascertained, that there is no passage on the coast of America below the arctic circle ; but beyond this it has not been ascertained whether this coast rounds off to the eastward in a continuous line into Old Greenland, forming what is named Baffin's Bay on the charts, or whether it does not turn in a contrary direction to the westward, and fall in with the general trending of the northern coast of America; which, from three nearly equidistant points, seen by Cook, Mackenzie and Hearne, may be considered to run within a degree either way of the 70th parallel of latitude.

Many reasons have been assigned for the latter supposition. The constant current that descends down the Welcome on the one side, and towards the coast of Greenland on the other; the logs of mahogany and the remains of the North American ox brought from the north-west by that

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