TOPOGRAPHICAL FEATURES. A19 
New Zealand to the Andaman Islands, north of Sumatra, has very 
distinctly a double curvature, the line bending from northwest to west, 
and then to the northwest again in Sumatra. We need not repeat the 
evidence that the whole should be viewed as portions of a single sys- 
tem; it is apparent upon any good chart. 
On the north and east of the Pacific, other great curved ranges may 
be distinguished. ‘To the north, the Aleutian Archipelago, six hun- 
dred miles long, stretches across between the two continents, America 
and Asia, with a strong convexity towards the ocean. From Kam- 
schatka, at the eastern termination of this archipelago, commences a 
second curve, which extends south by the Kuriles to Yeso, having a 
length of fifteen hundred miles. From Yeso commences a third (or 
rather from the island Sanghalian just north,) which stretches along 
Niphon to its southwest extremity, nine hundred miles long. A fourth 
extends from the termination of the preceding, through Kiusiu and 
other islands, to Loochoo and Formosa, about nine hundred miles. A 
fifth includes Formosa, Luzon, Palawan and Western Borneo, a dis- 
tauce of two thousand miles. 
The general forms of these curves are very similar; they are alike 
in being convex towards the Pacific, or to the sowtheast, and moreover 
they are so closely united at their extremities, and are so regularly 
rectangular at their intersections nith one another, that the whole 
naturally constitutes a single series, continuous over a length of seven 
thousand miles. 
Besides these great curvatures, there are often subordinate curves 
in the course of the ranges, conforming in general to the system to 
which they belong. 
In the East Indies, the north of Celebes makes an east and west 
line parallel with Java; eastward it gradually bends northward, and 
is connected with Southern Mindanao through Sanguir and other 
islands. 
The Sooloo Islands form a part of another similar curve connecting 
Northwestern Borneo with Western Mindanao, Negros Island and 
Panai. Both of these curves are convex towards the Pacific, like the 
larger curves before pointed out. 
The Ladrones have a slight curvature (see chart); and if we may 
connect with the curving line, the islands Mackenzie, Yap, and the 
Pelews, we distinguish another curve of corresponding character and 
form with those already mentioned. New Britain makes a similar 
curve between the west extremity of New Ireland and New Guinea. 
Like those of the Asiatic coast and others alluded to, it commences 
