successively formed seaward from the old, what dug up the sediment which formed the old, and lifted it up from where specific gravity had placed it, and carried it out to sea over a barrier not more than a few feet from the surface? Indeed, Sir Charles himself makes this majestic stream to tear up its own bottom to depths far below the top of the bar at its mouth. He describes the Mississippi as a river having nearly a uniform breadth to the distance of two thousand miles from the sea.[1] He makes it cut a bed for itself out of the soil, which is heavier than Admiral Smyth's deep sea water, to the depth of more than two hundred feet[2] below the top of the bar which obstructs its entrance into the sea. Could not the same power which scoops out this solid matter for the Mississippi draw the brine up from the pool in the Mediterranean, and pass it out across the barrier in the Straits? The currents which run over the bars and shoals in our rivers are fed from the pools above with water which we know comes from depths far below the top of such bars. The breadth of the river where the bar is may be the same as its breadth where the deep pool is, yet the current in the pool may be so sluggish as scarcely to be perceptible, while it may dash over the bar or down the rapids with mill-tail velocity. Were the brine not drawn out again from the hollow places in the sea, if would be easy to prove that this indraught into the Mediterranean has taken, even during the period assigned by Sir Charles to the formation of the Delta of the Mississippi—one of the newest formations—salt enough to fill up the whole basin of the Mediterranean with solid matter. Admiral Smyth brought up bottom with his briny sample of deep sea water (six hundred and seventy fathoms), but no salt crystals.
389. Views of Admiral Smyth and Sir C. Lyell.—The gallant admiral—appearing to withhold his assent both from Dr. Wollaston in his conclusions as to this under current, and from the geologist in his inferences as to the effect of the barrier in the Straits—suggests the probability that, in sounding for the heavy specimen of sea water, he struck a brine spring. But the
- ↑ "From near its mouth at the Belize, a steam-boat may ascend for two thousand miles with scarcely any perceptible difference in the width of the river."—Lyell, p. 263.
- ↑ "The Mississippi is continually shifting its course in the great alluvial plain, cutting frequently to the depth of one hundred, and even sometimes to the depth of two hundred and fifty feet"—Lyell, p. 273.
