65 



an additional reason for the development of efficient madia. 



4. Physical, Chrmical and Biological Unity in the Sea 



In the preceding pa2:es we h^ve, for the sake of clarity, 

 outlined certain underlying oiologic aspects of Oceanography as 

 though the marine environm^^nt were physically and chemically a 

 stable thing, controlling while in no way affected by the activities 

 of life within it. But this is far from the truth. In a practical 

 way the biolo2:ist may, if he chooses, regard Biology as the apex of 

 the oceanographic pyramid, with Physics and Chemistry as its bases; 

 actually, however, the oceanic situation is dynamic, not static, 

 better represented as 9 vortex (mioved by the activities of organisms 

 and by solar energy) of materials through living matter back asrain 

 to the inorganic physical and chemical end-states. That is to say, 

 while the nature of the sea water governs the lives of the animals 

 and plants that inhabit it, at the same time the functions of the 

 latter are as constantly altering the nature of their environment 

 in a way to which we see nothing comparaole on land. Perhaps the 

 most obvious exarr.ple of this (one alres.dy mentioned) is the constant 

 draft that so many animals and plants make on the water for the 

 materials with which they build their sleletons. As a result of 

 these drafts vast quantities of lime and of silica are constantly 

 being withdrawn. And while some of this g-oes back into solution 

 when the organism.s die, other vast quantities accumulate on the sea 

 floor, in deposits of lime compounds, and of silicates. 



On the whole, by this process, lime is accumulating toward the 

 equator, and around the coast lines, silica toward the poles and in 

 the ocean deeps. But, although we may temporarily find the water 

 nearly denuded of one or another substance, on the whole the rela- 

 tive proportion of its solutes is close to constant over all the 

 oceans. How, then, is the loss made 0;oodT A.ni what part does liv- 

 ing matter play in transf ormiing the great preponderance of carbon- 

 ates that characterize the saline load carried into the sea by river 

 water, into the great preponderance of chlorides that is everywhere 

 and at all times characteristic of sea water and also characteristic 

 of protoplasm? '<Vhy is it that lime accuaiulst^s more rapidly on the 

 bottom in shoal water than in deep? Is the solvent power of deep 

 water the greater, as has often been supposed, or have we to do with 

 somie bacterial action? While land drainage, added to whatever salt 

 may have been in the sea from the beginning aids in the maintenance 

 of the present stable stat^, the agent back of the stable state is 

 life; hence, at bottom the composition of the sea water is a biolog- 

 is as much as a chemical problem, even thourrh in many cases its 

 solution may come only via Chemistry. 



The mass productions of plants in the sea withdraws temporarily 

 from circulation the nutri^^nts they need, and there is a certain 

 permanent loss after their death, as of nitrates decomposing to the 

 gaseous state, and of phosphates going into che;nical union with 

 bottom sedim^ents. Just how are these losses made up so that the 

 balance is maintained? How far is the pulse in the availaole supply 

 of these nutrient substances in the sea responsible for the sudden 

 outbursts of unicellular plants in such unbelievable num^bers that 

 they are the most spectacular events in miarine economy: "explosions 

 de la vie" as these sudden developments of great miasses of livinsc 

 matter have been named? Is it their exhaustion of the water that 



