(6.) The Russian expeditions in the past and present centuries, which attempted to penetrate by the north-west coast of Novaya Zemlya, miscarried, because they sailed before the favourable season for navigation, and also because they had not the advantage of steam. (7.) How far the Gulf Stream has any share or influence in the favourable conditions for the navigation of the Eastern Polar Sea which have been described, cannot as yet be positively determined. The state of the ice, the observations which were made on the temperature of the sea, its colour and the animal life found in it, seem to speak in favour of the action of this current in that region. It is possible that the Gulf Stream may exercise its culminating influence on the west coast of Novaya Zemlya only at the beginning of September; for while the temperature of the sea in the months of July and August gradually fell from 45° F. to 36° F. in Lat. 75° N., and to zero and below it, still more to the north, we observed 39° F., September 6, in Lat. 78°, and 41° F., September 10, in Lat. 75° 30′. The temperature of the air was in all these cases considerably less than that of the water. If the unusually favourable state of the ice on the east of Spitzbergen should be ascribed to warm southerly currents of air, it may be replied that our observations specify the almost uninterrupted occurrence of north winds. It is also possible, that at the beginning and middle of summer the Gulf Stream may move slowly in a northerly direction along the coasts of Novaya Zemlya, and that towards autumn it spreads itself more and more to the west. Our observations proved the existence, in the eastern Novaya Zemlya seas, of a band of warm water, from thirty-six to forty feet deep, beneath which lies, without gradation, a colder stratum. It is evident that the unequal density of these strata prevents their mingling. This band of warmer water near North Cape is about 150 feet deep, with a temperature of nearly 45° F., but diminishes as it flows northward. The frequency of fogs and mists in the Novaya Zemlya Sea, and the squalls unknown to other Arctic regions, which are characteristic of a more southerly region, indicate also a current of warm water. How this warm current gradually cools towards the north, and becomes shallower, and how distinctly it divides into those strata of water of equal temperature, so characteristic of the Gulf Stream, is shown by three series of observations taken by Weyprecht at different latitudes, with the maximum and minimum thermometer of Casella:—