MESSRS. EDITORS—I noticed on page 150, this volume of the SCIENTIFIC AMERICAN, an article under the head of " Earth and Ocean Temperatures," in which it is stated that Lieut. Berryman, U. S. N., in his deep sea soundings, 500 miles north of Bermuda, found the greatest reliable depth ever obtained, and accompanying this, "thermometrical observations of a character indicating phenomena never before discovered, and which, at this moment, are an unsolved problem to the scientific world. In a long series of experiments, the temperature was indicated as existing ton, fifteen, and twenty degrees below the freezing point. This may be owing to the defective instruments, but if go, a consistency of error was preserved almost beyond the possibility of chance." I make no pretentious whatever to scientific attainments, but I wish to give two or three facts, in my own experience as a practical man, that may help to elucidate, or throw omo light upon this "unsolvedproblem." I have been engaged for over twenty years in the curing of provisions, more particularly and extensively hams; and first, I have observed that in very cold.winters, such as the last (1856-7), the temperature of the pickle in which the hams were immersed would fall to ten, fifteen, and twenty degrees below the freezing-point. The hams at. the same time would bo perfectly solid, and that, too, after being salted down in mild weather, for three or ibur weeks perhaps, before the commencement of the severely cold weather. Secondly: My establishment ia on the banks of the Ohio river ; the lower story is subject to be overflowed or submerged in OHr greatest floods in the winter or spring. On one occasion of a flood we had several open tubs of pickle on the lower floor, which we found impossible to move before the water came upon us. The river rose at least eight feet above the tops of the tubs of pickle. We supposed that the pickle—from the motion and agitation of the waves and water—would all be destroyed, and the tubs displaced. But we were surprised to find the tubs in their * places :md the pickle uninjured, and in full strength, after being thus submerged for eight days. These facts demonstrate two things : first, that pickle will not freeze or become solid at 20 below the freezing point; and second, that its specific gravity and density is such that it will not mingle with water without a considerable degree of agitation. I would, therefore, suggest the query to Lieut. Berryman, whether or not the peculiar thermometrical phenomena he discovered in the deep sea soundings were not owing to the increased density and saltness of the water at the bottom of the ocean. C. DUFFIELD. Louisville, Ky., March, 1858. [The deep sea soundings of Lieut. Berryman have done much to confirm a theory found in Lieut. Maury's works, as to the cause, or one of the causes, of the Gulf stream. Thus, for example, it is ascertained that, at a depth of two thousand feet, in tho straits of Florida, the temperature of the ocean is several degrees above freezing, while in the deep soundings on the telegraph route it is found the temperature is ten to fifteen degrees below the freezing point. Hence, according to well-known laws, the warm and light waters of the Gulf flow off toward the colder regions of the north. At the same time, the denser waters of the northern Atlantic make their way southward to restore the equilibrium. Thus, there are two currents, an upper and an under, flowing in contrary directions. The upper is the Gulf stream ; the under is frequently demonstrated by the fact of immense icebergs, reaching down thousands of feet below the surface of the ocean, and seen floating southward against the surface current.—Ens.