We had a fine gale from the S. W., and made rapid progress to the S. E. under canvass. Although the most perfect satisfaction with the course I had determined on appeared to prevail throughout the ship's company, Mr. Slim came to me in my cabin, when relieved from his watch on deck, and told me, that, however satisfactory my account of the matter might have been to the other officers and the crew, it was not satisfactory to his mind; and he should be glad to be informed how I accounted for the vast bodies of ice which had invariably stopped the progress of navigators in high latitudes, if my notions of great heat at the poles were correct? "Take a chair, Mr. Slim, and we will talk about it. In the first place, we have no account of any navigator having sailed to a higher southern latitude than 71°, and 82° appears, from the most authentic accounts, to be the highest northern latitude that has been visited. Navigators to these high latitudes have always found ice between the parallels of 70° and 80°, which space that profound philosopher, John Cleve Symmes, denominates the 'icy hoop.' It is true he has not taken the trouble to explain to the world, in a satisfactory manner, why and wherefore this narrow strip of ice should exist in that region; which omission, I judge, must have arisen from the circumstance of its being obvious to his capacious mind, that such a 'hoop' must necessarily exist, 'according to the laws of matter and motion.' The causes of it appearing to him perfectly simple, he could not suppose it necessary to state them to 'the most enlightened people on the face of the globe.' Now, sir, I will explain the matter to you. At the pole, that is, ninety degrees from the equator, there is seven months summer, without any interval of night, as I stated on deck; and when the sun has twenty-three and a half degrees of south declination, its rays must strike the pole, allowing but three degrees for the effect of refraction, on an angle of 26-1/2° with the plane of the horizon, and must appear nearly as high as in Scotland in the months of March and September. It is true it does not continue at this extreme declination for any great length of time. On the other hand, it does not recede so far as to withdraw its rays from the pole for a single hour during seven months of the year. This we know; and you can imagine, from the effect of a March sun, which in your country, Mr. Slim, loosens the icy fetters of winter, although withdrawn one half of the time, what must be its effect when exerting its influence for months without any interruption? Now in latitude 70°, with the exception of a few days, there is an interval of night the year round. In the winter months the climate cannot differ much from that of the pole. The cold is then no doubt severe, and forms ice in both those positions. In the early part of summer, that is, September, October, and November, there is at the pole a steady blaze of heat and light, which must