Penny Blood: Serial Sensation and Working-Class Entertainment — page 278: what you’re looking at

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

on. xx1.] DISTRIBUTION. OF VOLCANOS. 261 the Comoro Islands, and the Seychelles’, Now madreporitic rock, having probably grown upon a volcanic basis, need ferm no exception to the general law. And a glance at the map will show that neither New Caledonia, nor the Comoro and Sey- chelles Islands, are properly speaking Oceanic; the former belong- ing to the submerged ridge, which connects New Zealand with Australia and South-Eastern Asia, and the latter being a con- . tinuation of the axis of the great Island of Madagascar. The oceanic islands of the Atlantic are likewise volcanic. There is then it seems the important distinction to be drawn between coast-line and oceanic volcanos, that the former are connected with axes of elevation, and the latter not so. At the same time it is known that the volcanic oceanic islands rise from platforms elevated above the general level of the ocean floor. Still, if these were formed by compression, we ought to find some of the islands presenting exposures of the inclined strata of their higher ridges, which is not the case. Of what then do these platforms consist? Is it not possible that they may be accumulations of the ejectamenta of the volcanos themselves? With the fact before us that 665 feet of volcanic ash and tufa were pierced in sinking an Artesian well at Naples’, we may well believe that the enormous volcanos, whose ruins now remain in the shape of Oceanic islands, may have laid down an immense thickness of deposits around their bases. If this be a true account of the condition of these areas, the agency required for their production is one of fissuring without resulting elevation. ‘To account for this we can but speculate. It may be that the suboceanic crust 1s too rigid to yield to the compressing force, which, as will be remembered, is not exces- sive; for the doubt which we have felt is whether it 1s sufficient for the elevation of continental ranges. Or it may be that the fissures beneath the ocean do not stop short until they reach the surface, and so the compressing force has not time to act; for, as we have seen, when a fissure is completed to the surface compression ceases. Another suggestion to be offered 1s that, 1 Ibid. p. 69. < 2 ‘¢Comptes Rendus,’’ tome xivii1, p. 994. 1859. CONNEC OOO @ (CO)