'IHE DEPTHS OF THE OCEAN. 305 



not of plants ; for, characteristic as tlic luxuriant development of 

 vegetiition of the temperate zones is of the sea bottom, the full- 

 ness and multiplicity of the marine Fauna is just as prominent in 

 the regions of the tropics. Whatever is beautiful, wondrous, or 

 uncommon in the great classes of fish and Echinoderms, jelly- 

 fishes and Polypes, and the Mollusks of all kinds, is crowded 

 into the warm and crystal waters of the tropical ocean — rests in 

 the white sands, clothes the rough cliffs, clings, where the room 

 is already occupied, like a parasite, upon the first comers, or 

 swims through the shallows and depths of the elements — while 

 the mass of the vegetation is of a far inferior magnitude. It is 

 peculiar in relation to this that the law valid on land, according 

 to which the animal kingdom, being better adapted to accommo- 

 date itself to outward circumstances, has a greater diffusion than 

 the vegetable kingdom — for the polar seas swarm with whales, 

 seals, sea-birds, fishes, and countless numbers of the lower 

 animals, even where every trace of vegetation has long vanished 

 in the eternally frozen ice, and the cooled sea fosters no sea- 

 weed — that this law, I say, holds good also for the sea, in the 

 direction of its depth ; for when we descend, vegetable life 

 vanishes much sooner than the animal, and, even from the depths 

 to which no ray of light is capable of penetrating, the sounding- 

 lead brings up news at least of living infusoria." — Schleiden's 

 Lectures, p. 403 — 400. 



561. Ignorance concernhig the depth of '■'■'blue water ^ — Until the 

 commencement of the plan of deep-sea soundings, as they have 

 been conducted in the American and English navies, the bottom 

 of what the sailors call " blue water" was as unknown to us as 

 is the interior of any of the planets of our system. Eoss and 

 Dupetit Thenars, with other ofiicers of the English, French, and 

 Dutch navies, had attempted to fathom the deep sea, some with 

 silk threads, some with spun-yarn (coarse hemp thieads twisted 

 together), and some with the common lead and line of navigation. 

 All of these attempts were made upon the supposition that when 

 the lead reached the bottom, either a shock would be felt, or the 

 line, becoming slack, would cease to run out. 



5G2. Early attempts at deep-sea soundings — unworthy of reliance. — 

 The series of systematic experiments recently made upon this 

 subject show that there is no reliance to be placed on such a sup- 

 j)osition, for the shock caused by striking bottom cannot bo com- 

 nnmicated through very great depths. Furthermore, the lights 



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