never be a source of depression of temperature. As a general result the Gulf Stream water is nearly uniform in temperature throughout the greater part of its depth; there is a marked zone of intermixture at the junction between the warm water and the cold, and the water of the cold indraught is regularly stratified by gravitation; so that in deep water the contour lines of the sea-bottom are, speaking generally, lines of equal temperature. Keeping in view the enormous influence which ocean currents exercise in the distribution of climates at the present time, I think it is scarcely going too far to suppose that such currents--movements communicated to the water by constant winds--existed at all geological periods as the great means, I had almost said the sole means, of producing a general oceanic circulation, and thus distributing heat in the ocean. They must have existed, in fact, wherever equatorial land interrupted the path of the drift of the trade-winds. Wherever a warm current was deflected to north or south from the equatorial belt a polar indraught crept in beneath to supply its place; and the ocean consequently consisted, as in the Atlantic and doubtless in the Pacific at the present day, of an upper warm stratum and a lower layer of cold water becoming gradually colder with increasing depth. I must repeat that I have seen as yet no reason to modify the opinion which I have consistently held from the first, that the remarkable conditions of climate on the coasts of Northern Europe are due in a broad sense solely to the Gulf Stream. That is to say that, although movements, some of them possibly of considerable importance, must be produced by differences of specific gravity, yet the influence of the great current which we call the Gulf Stream, the reflux of the great equatorial current, is so paramount as to reduce all other causes to utter insignificance. THE PHOSPHORESCENCE OF THE SEA --G. HARTWIG He who still lingers on the shore after the shades of evening have descended not seldom enjoys a most magnificent spectacle; for lucid flashes burst from the bosom of the waters, as if the sea were anxious to restore to the darkened heavens the light it had received from them during the day. On approaching the margin of the rising flood to examine more closely the sparkling of the breaking wave, the spreading waters seem to cover the beach with a sheet of fire. Each footstep over the moist sands elicits luminous star-like points and a splash in the water resembles the awakening of slumbering flames. The same wonderful and beauteous aspect frequently gladdens the eye of the navigator who plows his way through the wide deserts of ocean, particularly if his course leads him through the tropical seas.