160 THE PHYSICAL GEOGRAPHY OF THE* SEA. 



Upon the bottom of this current, then, there is a pressure of more 

 than fifty atmospheres. Have we not here a source of power that 

 would be capable of drawing up, by almost an insensibly slow 

 motion, water from almost any depth ? At any rate, it appears 

 that the effect of currents by traction^^OY friction, or whatever force, 

 does extend far below the level of their beds in shallow places. 

 Were it not so — were the brine not drawn out again — it would 

 be easy to prove that this indraught into the Mediterranean has 

 taken, even during the period assigned by Sir Charles to the form- 

 ation of the Delta of the Mississippi — one of the newest forma- 

 tions — salt enough to fill up the whole basin of the Mediterranean 

 with crystals. Admiral Smyth brought up bottom with his briny 

 sample of deep sea water (six hundred and seventy fathoms), but 

 no salt crystals. 



436. The gallant admiral — appearing to withhold his assent 

 both from Dr. Wollaston in his conclusions as to this under cur- 

 rent, and from the geologist in his inferences as to tliQ effect of 

 the barrier in the Straits — suggests the probability that, in sound- 

 ing for the heavy specimen of sea v/ater, he struck a brine spring. 

 But the specimen, according to analysis, was of sea water, and 

 how did a brine spring of sea water get under the sea but through 

 the process of evaporation on the surface, or by parting with a 

 portion of its fresh water in some other way ? 



437. If we admit the principle assumed by Sir Charles Lyell, 

 that water from the great pools and basins of the sea can never 

 ascend to cross the ridges which form these pools and basins, then 

 the harmonies of the sea are gone, and we are forced to conclude 

 they never existed. Every particle of water that sinks below a 

 submarine ridge is, ipso facto, by his reasoning, stricken from the 

 channels of circulation, to become thenceforward forever motion- 

 less matter. The consequence would be "cold obstruction" in 

 the depths of the sea, and a system of circulation between differ- 

 ent seas of the waters only that float above the shoalest reefs and 

 barriers. I do not believe in the existence of any such imperfect 

 terrestrial mechanism, or in any such failures of design. To my 

 mind, the proofs — the theoretical proofs — the proofs derived ex- 

 clusively from reason and analogy — are as clear in favor of tliis 



