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oler sometimes, sometimes very near upon a par, and sometimes warmer than the sea-water at the depth of about 100 fathoms, according as the preceding changes of the temperature of the air, or the direction and violence of the wind happen to fall out. For it is to be observed, that these experiments were always made when we had a calm, or at least very little wind; because in a gale of wind, we could not have been able to make them in a boat. Another probable cause of the difference in the temperature of the sea-water in the same high latitude, undoubtedly must be sought in the ice; in a sea covered with high and extensive ice islands, the water should be colder than in a sea which is at a great distance from any ice."--F. This table is evidently too confined, and made up of too few elements, to justify almost any general inferences. The subject is certainly a curious one, and merits full investigation, but presents very considerable difficulties, as many circumstances, which are likely to modify the result, may escape notice during the experiments. It has been said, that as water is most dense at from 37 to 39 Fahrenheit, this may be presumed to be the mean temperature at the bottom of the sea; but such hypothetical deductions are, perhaps, entitled to little confidence. It may however be safely enough presumed, that the temperature of the sea is kept tolerably uniform on the well-known principle of statics, that the heavier columns of any fluid displace those that are lighter. The waters of the ocean, perhaps, are the great agent by which the average temperature of our globe is preserved almost entirely invariable. We shall have an opportunity, in the account of another voyage, to make some remarks on this subject, and to notice more exact experiments than those just now mentioned.--E. [8] "On this day, we had an alarm that one of our crew was overboard, upon which we immediately put about, but seeing nothing, the names of all persons on board the vessel were called over, and none found missing, to our great satisfaction. Our friends on board the Adventure, whom we visited a few days after, told us they had indeed suspected by our manoeuvre, the accident which we had apprehended, but that looking out on the sea, Captain Furneaux had plainly observed a sea-lion, that had been the cause
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