GENERAL FEATURES OF THE EARTH. 66 



there are the Samoari (5) and Tarawan (8) groups, and others inter- 

 mediate ; still northwestward there are the Radack and Ralick groups 

 (9, 10), and in 20° N., on the same line, Wakes Island. 



(or.) The chain, as is seen, consists of a series of parallel ranges, 

 succeeding and overlapping along the general course, in the manner 

 illustrated on page 19, when speaking of mountains, (b.) It varies its 

 course gradually from west-northwest at the eastern extremity to north- 

 northwest at the western, (c.) Its mean trend is northwest-by-west 

 (N. 56° W.), the mean trend of all the groups of the northwesterly 

 system in the ocean, (d.) The chain is a curving chain, convex to the 

 southward, and marks the position of a great central elliptical basin of 

 the Pacific having the same northwesterly trend. The Hawaian is on 

 the opposite side of it, slightly convex to the north. 



The Marquesan range (12, Fig. 27) lies in the same line with the Fanning group (13) 

 to the northwest, just north of the equator; and, if a connection exists, another great 

 chain is indicated, — a Marquesan chain. 



(3.) Australasian chain (Fig. 28). — New Hebrides (K) and New 

 Caledonia (M) belong to the Australasian island-chain. The line of 

 New Hebrides is continued northwestward in the Salomon group and 

 New Ireland (I), though bending a little more to the westward, and 

 terminates in Admiralty land (G), near 145° E., where it becomes 

 very nearly east-and-west : the length of the range is about 2,000 

 miles. Taking another range in the chain, New Caledonia (M), the 

 course is continued in the Louisiade group (H) ; then the north side 

 of New Guinea(E), which continues bending gradually till it becomes 

 east-and-west, near 135° E. In the southeast, belonging to the same 

 general line, there is the foot of the New Zealand boot (O). The coral 

 islands between New Caledonia and Australia appear also to be other 

 lines in the chain. 



From New Guinea (E, F), the east-and-west course is taken up by 

 Ceram (D), and again, more to the south, in the Java line of islands 

 (A, B, C) ; and from Java (B) the chain again begins to rise north- 

 ward, becoming northwest finally in Sumatra (A) and Malacca. 



The several ranges make up one grand island-chain, with a double 

 curvature, the whole nearly 6,000 miles long. In figure 28, a line 

 stands for each group, and indicates its course. The composite nature 

 of the chain is here apparent ; as also the curving course, in connec- 

 tion with a prevailing conformity to a northwesterly trend. 



(4.) Blending of the Australasian and Polynesian island- chains. —■ 

 The two chains blend with one another in the region of the Carolines. 

 (11, Fig. 27.) This large archipelago properly includes the Ralick and 

 Radack groups (9, 10). At the Gilbert group (8) the Polynesian 

 chain divides into two parts, — the Ralick and Radack ranges. But 



