348 PHYSICAL GEOGRAPHY. 



progressively to its present level, while Lower Egypt emerged again from its surface on 

 the one side, and the fertile valleys of Tarragon, Valencia, and Murcia on the other. 

 This is not a modern geological reverie, but the opinion of the ancient geographers, 

 Strabo and Eratosthenes, founded upon the configuration of the land, and a traditional 

 report of some great catastrophe in early ages, to the occurrence of which a different sen- 

 timent, which impressed the mind of antiquity, still points, that the irruption was made 

 by the waters of the Atlantic. 



The Phoenicians the earliest known navigators of the Mediterranean are said to 

 have come, in thirty days' sail, with an easterly wind, to the " weedy sea." This is a 

 modern denomination of the Atlantic, Mar de Sargasso, in the language of the Spanish 

 and Portuguese sailors. The occurrence of floating sea- weed, Fucus natans, is one of its 

 peculiarities. It is found in immense quantities, in two separate regions of the Atlantic, 

 covering the ocean like a mantle, a little to the west of the meridian of Fayal, one of the 

 Azores, between 25 and 36 of latitude, where it forms a vast marine meadow. The 

 other region occupies a smaller space between lat. 22 and 26, and about long. 70 and 

 72, two hundred and seventy-six miles to the east of the Bahamas. Though there is 

 a species of sea-weed, observed by Lamouroux, with stems upwards of eight hundred 

 feet long, yet, in the latitude stated, the weed is not fixed to the bottom, but floats in 

 separate masses on the surface of the water. It owes its origin doubtless to submarine 

 rocks, which continually replace at the surface what is carried off by the equinoctial cur- 

 rents, the growth of marine cryptogamia being extremely rapid. There is some obscurity 

 resting upon the manner in which these weeds are uprooted, at depths where it is gene- 

 rally thought the sea can only experience a very slight agitation. Lamouroux, however, 

 observes, that if the fuci adhere to the rocks with the greatest firmness before the display 

 of fructification, they separate with great facility after that period ; and, added to this, 

 the fish and the molluscas gnawing the stems may contribute to the separation in ques- 

 tion. Humboldt observed a vine-leaved fucus vegetating at the bottom of the ocean, at 

 the depth of 192 feet, notwithstanding which its leaves were as green as those of our 

 grasses. He estimated that, at such a depth, the fucus could only have received light 

 equal to half of that supplied by a candle at the distance of a foot. This fact, and others 

 of a kindred nature, offer formidable difficulties to the common opinion, that absence of 

 light must always produce blanching ; and clearly indicate that it is not under the influ- 

 ence of the solar rays alone that the carburet of iron is formed, the presence of which gives 

 the green colour to the parenchyma of plants. Upon a scale equally grand and extensive, 

 the ocean exhibits the boundless profusion of creative power, in the animal as well as the 

 vegetable life, of which it is the repository. There is a portion of the Greenland sea 

 occupied by microscopic Medusan races, to an extent of not less than twenty thousand 

 square miles ; yet Scoresby estimates that two square miles must comprehend 

 23,888,000,000,000,000 of these creatures a number which he illustrates by observing, 

 that to count it would require 80,000 persons, and a period equal to the interval between 

 the present and the Creation. 



Cape Horn. 



