248 PHYSICAL GEOGRAPHY OF THE SEA, AND ITS METEOROLOGY. 



ter behind. The surface vv^ater thus becomes specifically heavier, 

 and sinks. On the other hand, the httle 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 be- 

 comes specifically lighter, and up it goes, ascending to the top with 

 increased velocity, to take the place of the descending column, 

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

 powers of secretion, are competent to exercise at least so7ne degree 

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

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

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

 physical geography? Their influences upon the economy of the 

 sea are like those outstanding quantities which the astronomer 

 finds in the periods of heavenly bodies. He calls them perturba- 

 tions ; for short, or even during considerable intervals, their efiects 

 may be inappreciable ; for they are pendulums that require ages for 

 a single vibration ; but unless there was a balance provided some- 

 where, they would, during the progress of time, accumulate their 

 small perturbations so as to produce disorder, and finally cause the 

 destruction of worlds. So, too, mth the salts of the sea, and 

 those little microscopic inhabitants of its waters. They take care 

 of its outstanding quantities of solid matter, and by their influence 

 preserve harmony in the ocean. It is immaterial how great or 

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

 small, it is cumulative ; and we therefore may rest assured it is 

 not a chance influence, but it is an influence exercised 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. 

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

 'Hieir physical ccouomy of nature are such as to require that the 



reiatiuns. various kiuds of marine animals, whose secretions 



are calculated to alter the specific gravity of sea water, to destroy 

 its equilibrium, to beget currents in the ocean, and to control its 

 circulation should be distributed according to order. Upon this 

 supposition — the like of which natm-e warrants throughout her 

 whole domain — we may conceive how the marine animals of 

 which we have been speaking may impress other featm-es upon 

 the physical relations of the sea by assisting also to regulate cK- 

 mates, and to adjust the temperature of certain latitudes. For in- 



