of hundreds of other substances and materials. Hundreds of thousands 

 of tons of sodium chloride continue to be taken from the sea each year. 

 The technological advances of recent years has caused the erection of 

 enormous plants for the recovery of various compounds of magnesium 

 and bromine from sea-water. In several localities, using very efficient 

 evaporators, water itself is being distilled from the sea and sodium 

 chloride, together with compounds of magnesium, potassium, and 

 bromine, recovered from the brines. 



With the ever-increasing population of the world the problem of 

 sufficient food supplies is becoming acute in many quarters of the world. 

 Since the cessation of hostilities considerable impetus has been given 

 to the exploration of the sea, particularly of the Pacific, as a source 

 of future food by groups within the United Nations Organization. By 

 treaty between several nations various international commissions have 

 come into being to study fishery resources and to write regulations 

 ensuring intelligent use of these resources. 



The importance of vitamins to the well-being of man is now universally 

 known. Products of the sea, particularly fish-livers, have supplied 

 great quantities of these spark plugs of nutrition. I well recall some 

 years ago when my colleague Dr. W. F. Thompson, then in charge of 

 the International Halibut Commission, urged the halibut fishermen to 

 preserve the fish livers for sale to pharmaceutical houses. At first 

 the suggestion was considered rather idiotic by the fishermen. To-day, 

 however, the money derived from the sale of halibut Hvers more than 

 pays the full cost of operation of a fishing-vessel. By-products of the 

 fishing industry are being extensively used as the source of fish-oils, 

 cattle food, and fertilizers. 



Thus with increasing knowledge of the sea and its products, coupled 

 with advances in technological processes, man is learning to use more 

 effectively the material available to him in the sea. However, in no 

 manner has he attempted to exploit the sea as he has the land. Scientific 

 farming of the land has given rise to greater productivity ; animals 

 have been bred to give greater quantities of milk, or of meat, or of wool. 

 Many and better plants, unknown to our grandfathers, have been created. 

 All of this has come about by an orderly process of research and education, 

 fostered by basic research in the fundamental sciences. Attempts to 

 make the sea more productive, to produce better and more useful marine 

 plants, fishes, and mammals have scarcely been made. 



Large areas of land were unproductive because of lack of water, but 

 by building dams and bringing water the deserts, rich in nutrient materials 

 were made to bloom and produce. There are vast expanses of ocean 

 unproductive because of lack of nutrient salts, yet from oceanographic 

 studies it is known that a few metres below the thermocline of these 

 barren areas and out of contact with the life-giving energy of the sun are 

 unlimited supplies of nutrient salts. Perhaps some day means may be 

 devised whereby these rich waters will be brought nearer to the surface 

 to promote growths of phytoplankton upon which the fishes and mammals 

 of the sea may graze. 



The potential energy of the rivers of land areas has been converted 

 to useful electrical energy, but the enormous potential energy available 

 within the sea yet remains to be utilized. 



Exploration of the continental shelves, using geophysical instruments, 

 is being conducted in many quarters in the search for oil and minerals. 



141 



