THE BASIN OF THE ATLANTIC. 215 



fresh water, which, being hghter than that of the ocean, remains 

 for a considerable time at or near the surface. Here the micro- 

 scopic organisms of the deep-sea lead are continually at work, se- 

 creting this same hme and soda, &c., and extracting from the sea 

 water all this solid matter as fast as the rivers bring it down and 

 empty it into the sea. 



Thus we haul up from the deep sea specimens of dead animals, 

 and recognize in them the remains of creatures which, though invis- 

 ible to the naked eye, have nevertheless assigned to them a most 

 important office in the physical economy of the universe, viz., that 

 of regulating the saltness of the sea (§ 342). 



This view suggests many contemplations. Among them, one 

 in which the ocean is presented as a vast chemical bath, in which 

 the solid parts of the earth are washed, filtered, and precipitated 

 again as solid matter, but in a new form, and with fresh properties. 



Doubtless it is only a re-adaptation, though it may be in an im- 

 proved form, of old, and, perhaps, effete matter, to the uses and 

 well-being of man. 



These are speculations merely ; they may be fancies without 

 foundation, but idle they are not, I am sure ; for when we come 

 to consider the agents by which the physical economy of this our 

 earth is regulated, by which this or that result is brought about 

 and accomplished in this beautiful system of terrestrial arrange- 

 ments, we are utterly amazed at the offices which have been per- 

 formed, the work which has been done, by the animalculse of the 

 water. 



459. But whence come the little calcareous shells which 

 Brooke's lead has brought up, in proof of its sounding, from the 

 depth of two miles and a quarter ? Did they live in the surface 

 waters immediately above ? or is their habitat in some remote part 

 of the sea, whence, at their death, the currents were sent forth as 

 pall-bearers, w^th the command to deposit their remains where 

 the plummet found them ? 



460. In this view, these little organisms become doubly inter- 

 esting. When dead, the descent of the shell to its final resting- 

 place would not, it may be supposed, be very rapid. It would 

 partake of the motion of the sea water in which it lived and died, 

 and probably be carried along with it in its channels of circular 

 tion for many a long mile. 



