THE EXTENT OF THE OCEAN 5 



important part in ancient cosmogonies, and nearly ail the 

 myths and religions of primitive peoples contain accounts of 

 the origin of land and water, even where such people hâve 

 been for générations shut off from the sea — e.g., the Sonthals 

 of Chota Nagpore, India. Some of the older theorists believed 

 that the land surface of the globe miist exceed the water surface, 

 since the Creator made the world for human habitation. 



Mercator (1569) put forward a theory of equilibrium 

 according to which the land masses of the Northern and 

 Southern Hémisphères balance one another, and also the land 

 and water areas of the globe were approximately equal, as, 

 indeed, was shown on his later charts. 



The first idea was shaken by the voyages of Tasman, who 

 was sent out in 1642 on an expédition for the discovery of the 

 " Great South Land," and finally exploded by Cook's great 

 voyage of discovery. 



The earliest serious attempts to measure the extent of the 

 land and water surfaces- of the globe were those of English 

 investigators. 



Dr. Long in 1742 estimated the ratio of land to water to be 

 I to 2'8i, or 26 to 74 per cent. At that time the Polar régions 

 were not at ail well known. In 1837 Prof essor Rigaud of 

 Oxford made a similar calculation, and estimated the ratio of 

 land to water to be 266 to 734 per cent. 



It would be an interesting subject for research to détermine 

 the history of the ideas of land and water distribution on the 

 earth's surface. 



The distribution of land and water on the surface of the 

 globe is most irregular. . 



North of the Equator, instead of the average 70'8 per cent, 

 water, we find only 607; whereas south of the Equator the 

 water average is So'g. It follows that 43 per cent, of the seas 

 and océans are in the Northern Hémisphère, 57 per cent, in 

 the Southern Hémisphère. 



If we divide the earth's surface into zones of 5° of latitude, 

 it is only between 15° and 20° N. that we fînd the distribution 



