GENERAL FEATURES OF THE EARTH. 35 



(2.) Pacific and Atlantic Oceans. — The trend of the Pacific Ocean 

 as a whole corresponds with that of its central chain of islands, and 

 very nearly with the mean trend of the whole. It is a vast channel, 

 elongated to the northwest. The range of heights along northeastern 

 Australia (N, Fig. 28) runs northwesterly and passes by the head of 

 the great gulf (Carpentaria) on the north; and the opposite side of 

 the ocean along North America, or its bordering mountain-chain, has 

 a similar mean trend. A straight line drawn from northern Japan 

 through the eastern Paumotus to a point a little south of Cape Horn 

 may be called the axis of the ocean. This axial line is nearly half 

 the circumference of the globe in length, and the transverse diameter 

 of the ocean full one-fourth the circumference : so that the facts relat- 

 ing to the Pacific chains must have a universal importance. 



The North Atlantic Ocean trends to the northeast, — or at right 

 angles, nearly, to the Pacific : this is the course of the coasts, and 

 therefore of the channel. Taking the trend of the southeast coast of 

 South America as the criterion, the South Atlantic conforms in direc- 

 tion to the North Atlantic. 



The Asiatic coast of the Pacific has the direction of the northeast- 

 erly system. The course is not a nearly straight line, like the corre- 

 sponding eastern coast of North America, but consists of a series of 

 curves, which series is repeated in the island-chains off" the coast and 

 in the mountains of the country back. Moreover, the curves meet one 

 another at right angles. 



The last one, which is 1,800 miles long, commences in Formosa, and 

 extends along by Luzon, Palawan, and western Borneo {b a, Fig. 28) 

 to Sumatra, and terminates at right angles with Sumatra ; and another 

 furcation of it (d c) passes by eastern Borneo or Celebes, and termi- 

 nates at right angles with Java arid the islands just east. The rectan- 

 gularly of the intersections is thus preserved ; and the curve of the 

 Australasian chain has in this way determined the triangular form of 

 Borneo. 



The Aleutian Islands (range No. 1) make a curve across from America to Kam- 

 chatka, in length 1,000 miles. The Kamchatka range (No. 2) commences at right 

 angles with the termination of the Aleutian, and bends around till it strikes Japan at a 

 right angle. The Japan range (No. 3) commences north in Saghalien, and curves 

 around to Corea. The Loochoo range (No. 4) leaves Japan at a right angle, and curves 

 around to Formosa. The Formosa range (No. 5) is explained above. There is appar- 

 ently a repetition of the Formosa system in the Ladrones near longitude 145° E. 



(3.) East and "West Indies. — The general courses in the East 

 Indies have been mentioned on pp. 33, 34. In the West Indies and 

 Central America there is a repetition of the curyes in the East Indies. 

 The course of the range along Central America corresponds to Su- 

 matra and Java ; and the line of Florida and the islands to the south- 

 east makes another range in the same system. 



