THE SUN AND THE HARVEST OF THE SEA? 
By WaA.po L. ScHMITT 
Head Curator of Biology, U. 8S. National Museum 
[With 10 plates] 
None of the preceding Arthur lectures, of which this is the four- 
teenth, have particularly concerned themselves with the sun’s relation 
to life in the oceans and the food that man harvests from that abund- 
ant life. Those who attended the previous lectures or read them as 
published perhaps gleaned a few memorable facts regarding the sun 
and its importance in the daily life of man and to the world about 
him, but others may not yet have had these facts presented to them. 
Therefore, I beg to recall at this point a few facts regarding the rela- 
tive size of the sun and the earth, the land area of the earth as com- 
pared to the sea, and the sun’s output of energy upon which all living 
things ultimately depend. 
RELATIVE SIZE OF SUN, EARTH, AND SEA 
Fabre, in his delightful series of little essays entitled “This Earth 
of Ours,” tells us that the sun, as compared to the earth, is enormously 
large—over a million times larger than the earth; that if the sun’s 
center coincided with that of the earth, it would reach about as far 
beyond the moon as the moon is distant from the earth. The moon is 
some 240,000 miles removed from the earth; its diameter is 2,160 
miles. The sun’s diameter is roughly 860,000 miles; that of the earth 
8,000 miles. Between the earth and the sun some 93 million miles of 
space intervene. 
From H. A. Marmer’s informative treatise on “The Sea” we learn 
that the area of the earth totals approximately 197 million square 
miles, of which 13914 million square miles (71 percent) are sea and 
5714 million square miles (29 percent) are land. The greatest ocean 
depth is 35,400 feet below the level of the sea; the highest mountain, 
Mount Everest, rises 29,000 feet above it. Though the average depth 
of the sea is only 2.386 miles (12,450 feet), the total volume of water 
in the oceans is 11 times that of all land above the level of the sea. 
1FWourteenth Arthur lecture, given under the auspices of the Smithsonian Institution 
March 5, 1946. 
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