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Show 194 IGNEOUS CAUSES TliE ANTAGO NIST POWER (Cb. XII. 'fi r is drifted down to the 1 tl other putrl es, o the one me ts, 1e tl case frost might be con- . If this were not le ' . 1 sea by nvers. · t power as we 11 as the action of amma sidered as an antagoms b their combined energy might and vegetable life, and thes~ y f that solid matter which is restore to con fm e nts a portfi on o untains and wastm. g cl1'f fis . . t the sea rom mo swept down m 0 h' ight a theorist repair the 'd f such mac mery m . By the al 0 • d d and rocky fragments bemg losses of the sohd Ian ' sahn baqueous regions f rom h'll . d d n annually to t e su 1 s carrie 'to w limestone an d sh a1 e , wb ile vegetation and frost of gram e, ' . h' h like the cliffs in Esch- . · ew mountams, w 1c ' . m1ght ratse n . . t f icebergs, intermixed w1th scholtz's Bay' might consls o vegetable mould. d . former volume that, in the known We have state . m a s a real antagonist power is · f the tgneous cause , operatiOn o b 1 the levelling action of run· "' d h' h may counter a ance . 1o. un wt IC. . and there seems no good reason for presummg nmg wa er' . d depressing force of earthquakes, to· that the ~pheavmg a~ u of e' ected matter by volcanos, gether with the heapm~ t P rest:re the superficial inequalimay not be fully adequa e .o . ts annually tend to lessen. 1. h · ·s and oceamc curren . ties w llC nver. . d from this source, the quanhty If a counterpOlse be del'lVe h for ever remain the and elevation of land ab~ve tf ::e: ~:~us causes, which, if same, in spite of the action o b e ~e to reduce the surface thus counteracted, may never e a 'l'b . m than that l to a state of eqm 1 rm of the earth more ne~r y n the other hand, the force which it has now attamed; and, o . ht thus continue for of the aqueous agents themselves mi~ the intensity of the . · d This permanence o f ever ummpa1re • t £ r any amount o · ti n would accoun o b powers now m opera o. the earth's crust, so far as t e disturbance or degradatiOn of . erned . provided mere quantity of movement or .decayr;sc~:::mplat:d. only that indefinite periods of tl.me ab' ses at particular 't f the d1stur mg cau As to the intens1 y o d' d for too short a Hi h as yet been stu Ie epochs, their e ects ave h i ns of ancient con· . time to enable us fully to compare t e s g Ch.XII.]' TO TilE ACTION OF RUNNING WATER. 195 vulsions with the permanent monuments left in the earth's crust by the events of the last few thousand years. But not. withstanding the small number of changes which have been witnessed and carefully recorded, observation has at least shown that our knowledge of the extent of the subterranean agency, as now developed from time to time, is in its infancy; and there can be no doubt that great partial mutations in the structure of the earth's crust are brought about in volcanic regions, without any interruption to the general tranquillity of the habitable surface. Some geologists point to particular cases of enormous illslocation of ancient date, and confessedly not of frequent occurrence, where shifts in the strata of two thousand feet and upwards appear to have been produced suddenly and at one effort. But they have been at no pains to prove that similar consequences could not result from earthquakes such as have happened within the last three thousand years. They have usually proceeded on a priori reasoning to assume that such convulsions were paroxysmal, and attended by catastrophes such as have never occurred in modern times. It would be irrelevant to the subject immediately under consideration to enter into a long digression on these topics, but we may remind the reader, that the subsidence of the quay at Lisbon to the depth of six hundred feet only gave rise to a slight whirlpool ; and we may thence infer the possibility of a sinking down or elevation four or five times as great, especially in deeper seas, without any superficial disturbance unparalleled in the events of the last century. If a certain sect of geologists were as anxious to reconcile the actual and former course of nature as they are eager to contrast them, they would perceive· that the effects witnessed by us of subterranean action on supramarine land, may not be a type of those which the submerged rocks undergo, and they would proceed with more caution when reasoning from a comparison between the accumulated results of disturbing causes in the immensity of past time, and those whiclr 02 |