Penny Blood: Serial Sensation and Working-Class Entertainment — page 280: what you’re looking at

Machine-transcribed from the original scan — historical spelling and the odd misread are preserved.

CH. Xx1.] DISTRIBUTION OF VOICANOS. 263 water were removed, the same fact would be apparent, that the volcanos occupy an elevated tract, which borders the great con- tinent. Such an arrangement of the vents, regarded as the indication of systems of fissures below, of which probably a few only reach the surface, 1s in accordance with our theory, that the same ultimate cause underlies the phenomena both of com- pression and of volcanic activity.. Richthofen has made the remark that “active volcanoes have been found to be particularly numerous in those regions where the narrow terminations of two continents verge towards connection, as in the case of Central America, between Alasca and Kamtschatka, and between Australia and Farther India’.” The crust movements of the last-named region, and of the sur- rounding oceans, have been made more familiar to us than those of most other parts of the world, through the researches of Dr Darwin on Coral Reefs. He has shown that the areas occupied by Atolls and Barrier reefs are sinking areas; while those in which active volcanos prevail are rising; as testified by the occurrence of beds of recent shells at considerable heights above the sea level, and corroborated by the fringing reefs without lagoon-channels, that encircle the islands. The chart prefixed to his work gives at a glance the relative positions of the sink- ing and rising areas within the coralline seas; and we perceive that the trains of volcanos, which’ are the most active in the world, are of the coast-line type, and that they follow the axial trend of the land masses. The rising areas are confined to comparatively narrow bands, bordered by the broad areas that are sinking. This arrangement of the masses agrees well enough with our section of a disturbed tract*, in which we see that, if compression were to affect the elevated ridge A, A would become part of a rising area, whilst wide regions at b, b, on either side of it would sink. We may, perhaps, conclude that the continent of Australia is at present in process of becoming united to Asia, as.we are led by geological reasons to believe that North and South America have been comparatively recently joined. 1 «*Natural System of volcanic rocks,” p. 79. 2 p. 182. COLA @ NOO (CO)