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Show 242 EARLY STATE OF THE OLOBB• state than the sea of the present time, and that d new actions beaan to be carried on over the lan ' the sea became~'the receptacle of new products. Bearing all those things in. mind, we ca!l carry our speculation back to the periOd of the first mtern~l action of the earth -the time when the first mount«.Un ridge (that ridge ~hich was in time to become the centre and spine of a continent), began to ascend from the bottom of the deep. We have already spo~en of the great pressure which must have opposed tts ascent · but we must bear in mind that that pressure was exactly balanced by the resistance of the bottom, so that, mighty as were the weights, both upward a~d downward, so nice was the poise, tha~ a s~ngle gram would have given it either t~e ~ne dtrectwn or the other. It is one of the beauties 111 the arrangeme,!lts of nature, and one which, though man must admue, his art can never imitate, that the gr.eat and. the small are both equally susceptible t.o ImpressiOns. Thus, though the weight of a contment w~s upon the surface which was to be eleva~e~ by the. mternal action, a few pounds would put 1t m motwn; and whatever was the state of the substances wh~n they began to ascend, the two pressures were .qmte s.uf ficient to brinu them to that state of cohesiOn whteh we find in rocks. In those parts of the ocean whi~h n:tay be regarded as covering the slopes of volcamc .ndges, there are still occasional displays of the actiOn of .those va~t powBrs; and there are in many places.dectded ~roof:s of that action having been at some ttme earned on in situations where it had ceased before the recor~!'\ of history began. It is important, too, to bear .w mind that the formation of large. tracts of all~vtal land so as to remove the sea to a dtsta~ce, occastons the internal action to cease. In that rtdge of m?untains in France which stands nearest to the Mediterranean on the riaht bank of the Rhone, there are. many ~xtinct vol~anoes; and the plain of Langue· HOTHAM ISLAND. 243 doc, which lies between those mountains and the sea, is alluvial, composed in many parts of sand, in others of gravel and stones, and in others, again, of shells,-the whole giving the clearest evidence of having been under the sea, or formed by the action of its waters upon the shores. The farther part of Italy and the island of Sicily are still volcanic countries. Vesuvius and Etna burn continually, and often pour out eruptions of melted matters; the whole of Calabria is subject to earthquakes ; and fires are continually burning in the little islands which lie nearly in the line between Vesuvius and Etna. One of the most recent displays of submarine action, extending above the surface, which has appeared in those seas, is HOTHAM ISLAND. That island, or rather the symptoms of its forma· tion were first. observed on the lOth of July, 1831 ; though on the preceding day quantities of charred sea plants and dead fish were observed floating on the surface ; and sounds resembling that of thunder |