430 PACIFIC OCHAN 
and the various terraces show. Indeed, the continents from the 
earliest period have from era to era been rising, though subject to 
oscillations which may not now have entirely ceased. This will be 
gathered from any geological treatise. 
If then the oceans were the regions of greatest contraction, these 
subsiding areas would be gradually deepening as long as contraction 
continued. Moreover, the tension, from its nature, would be exerted 
nearly horizontally. It would produce fractures over the subsiding 
surface until the strength was such as effectually to resist it. It 
would act also on the borders of the subsiding areas, with some me- 
chanical advantage, and the effects of lateral pressure would therefore 
appear along the borders of continents, in fissures, disruptions, eleva- 
tions and subsidences. ‘These are necessary effects of the cause; they 
must have happened, if the earth cooled unequally. 
Looking to the continents, we observe that these very effects have 
happened. Foldings, dislocations and lofty elevations, are common in 
the vicinity of the oceans, and make a crimpled border to the great 
oceanic basins. ‘The volcanoes of the globe extend in lines generally 
along the same region, and metamorphic and volcanic action have 
often been most rife on the oceanic side of the lofty mountain eleva- 
tions bordering the sea. Illustrations of this fact have been pointed 
to in North America, whose interior is to a great extent a region of 
scarcely disturbed stratification, while on one side rise’the Rocky 
Mountains, a lofty border to the Pacific, and on the other, the Appa- 
lachians, a corresponding border to the Atlantic; and the volcanoes 
of the former region as well as the metamorphic changes and feldings 
of the latter, are on the oceanic side of the mountains; moreover the 
direction and steeper west than east slopes of the Appalachian folds 
are just what lateral action over the Atlantic should produce.* The 
Andes also, have their volcanic action and principal dislocations on 
the side towards the neighbouring ocean. We observe too that the 
largest ocean, the Pacific, is encircled by volcanoes, the line extend- 
ing from New Zealand, by the Philippines, Japan, and Kamschatka, 
around by the Aleutian Archipelago to Northwest America, and south 
by the Andes to Tierra del I'uego; and recent discoveries have shown 
that Deception Island is not the only volcanic region on the southern 
border of this ocean. Around the Pacific, moreover, we have some 
of the highest mountains of the globe. Bordering the Atlantic, on 
the contrary, we have on the western shores, no voleanoes and compara- 
tively low mountains, and but few points of eruption on the eastern. 
* American Journal of Science, ii. ser., ill. 182. 
