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in Ike Western Arctic Sea. SJ they were placed. Hence has arisen one of the greatest obstacles we have met with in performing astronomical and geographical ob servations. The instruments being constructed of brass, that they may not be acted upon by the magnetic power, have often become so cold that it becomes highly painful to handle them. As the winter advances the cold will, no doubt, become more and more intense: it will then, it is to be feared, be in some cases im possible to use some of our most valuable instruments in the open air, where alone they can be used. The sensation produced by handling metals in the open air is similar to that excited by the opposite extreme of heat, and the skin is affected and even taken off in the same manner as by burning. One proof of the intense cold communicated to the metallic instruments by the open air is this, that when they are carried into the warmer atmosphere of the cabin, the moist vapour there is instantly condensed round the instruments, and covers them with a coating of ice, which again thaws as the metal acquires the temperature of the cabin. The sun having for some time been drawing nearer and nearer to the day of his departure for three months to come, at last, on Thursday, the fourth of November, he was, according to the alma nack, to take his dreaded leave, and consign us over to a long and melancholy night. But the invidious atmosphere was so obscured by clouds, that even those who mounted to the top of the nearest hill were not permitted to take a parting look of the mariner’s best and truest friend and conductor in his wanderings over the [rath- less deep. By comparing the instant of his actual disappearance below the horizon with the instant of his astronomical disappear ance, information might have been obtained respecting the re fracting power of the atmosphere on the meridian in a very low temperature. Of this power a curious instance occurred just a week afterwards ; for an officer of the Hecla having gone up to the mast-head from curiosity, there perceived nearly one half of the sun’s body above the horizon. In this case the elevation produced by the refraction must have been at least two de grees. The day after the sun left us, the temperature of the air (I need not add in the shade, for we are always now in the shade) was 16°, or 16 degrees below zero on Fahrenheit’s scale ; that of the water at the surface was + 2H®, or 28 degrees above zero, and that of the water, at the depth of five fathoms under the ice, was as high as + 30°. The specific gravity of the water at the sur face, at a temperature of 52°, was 1*0264. Experiments were made at the same time to ascertain the elec tric state of the atmosphere, both when clear and when clouded, and even during a display of the aurora borealis ; hut always without any effect. The chain employed to attract the electric raat- Voyages, Vol. V. I