THE SALTS OF THE SEA. I97 



matter enough to build continents of. And, also, we have to in- 

 quire as to the extent to which equilibrium in the sea is disturbed 

 by the salts which evaporation leaves behind. 



550. Thus, when we consider the salts of the sea in one point 

 of view, we see the winds and the marine animals operating upon 

 the waters, and, in certain parts of the ocean, deriving from the 

 solid contents of the same those very principles of antagonistic 

 forces which hold the earth in its orbit, and preserve the harmo- 

 nies of the universe. 



551. In another point of view, we see the sea-breeze and the 

 sea-shell, in performing their appointed offices, acting so as to give 

 rise to a reciprocating motion in the waters ; and thus they impart 

 to the ocean dynamical forces also for its circulation. 



552. The sea-breeze plays upon the surface ; it converts only 

 fresh water into vapor, and leaves the solid matter behind. The 

 surface water thus becomes specifically heavier, and sinks. On 

 the other hand, the little marine architect below, as he works 

 upon his coral edifice at the bottom, abstracts from the water 

 there a portion of its solid contents ; it therefore becomes specif- 

 ically lighter, and up it goes, ascending to the top with increased 

 velocity, to take the place of the descending column, which, by 

 the action of the winds, has been sent down loaded with fresh 

 food and materials for the busy little mason in the depths below. 



552. Seeing, then, that the inhabitants of the sea, with their 

 powers of secretion, are competent to exercise at least some degree 

 of influence in disturbing equilibrium, are not these creatures en- 

 titled to be regarded as agents which have their offices to perform 

 in the system of oceanic circulation, and do not they belong to its 

 physical geography? It is immaterial how great or how small 

 that influence may be supposed to be ; for, be it great or small, 

 we may rest assured it is not a chance influence, but it is an in- 

 fluence exercised — if exercised at all — by design, and according to 

 the commandment of Him whose " voice the winds and the sea 

 obey." Thus God speaks through sea-shells to the ocean. 



553. It may therefore be supposed that the arrangements in the 

 economy of nature are such as to require that the various kinds 

 of marine animals, whose secretions are calculated to alter the 



