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Show 132 NEWER PLIOCENE PERIOD. [Ch.X. m friend Captain Hall for additional details, and ~e immc-y . . . 1 nuscript notes, requestmg me to diately sent me Ius or1gma rna . . . I them I find the followmg mterestmg make free use of them. n r 11 · . d . h' rinted account. ' The va ey Is com-passacres om1tte m IS P 0 ' d the sea . if the roads, therefore, are the Pletely open towar 8 ' • · beaches of an anct·e n t 1a ke , it is difficult to Imagme. a cata. s-trophe su ffi C.i en tlY v iolent to carry away the barrier whtch shoul d not at t h e sa me time obliterate all traces of the beaches. I fin d I. t d'1f fi cu lt al so to account for the water-worn character of a1 1 th e s tones ' for they have. the appearance of havm· cr trave1 1 ed ove r a great distance, bemg ·w ell rounded and dressed. They are in immense quantity too, and much more h ld Xpect to find on the beach of any lake, and t an one cou e seem more prope'rly to belong to th~ ~cean.' . we entertained a strong susptcwn, before readmg these notes, that the beaches were formed ~y the waves of the Pacific, and not by the waters of a lake; m other words, that they bear testimony to the successive rise of the land, not to the repeated fall of the waters of a lake. W ~ have before cited the proofs adduced by M. Boblaye, that m the Morea there are four or five ranges of ancient sea-cliffs, one above the other, at various elevations, where limestone precipices exhibit lithodomous perforations and lines of ancient littoral caverns*. If we discover lines of parallel upraised cliffs, we ought to find parallel lines of elevated beaches on those co~sts where the r~cks are of a nature to retain, for a length of ttme, the marks tmprinted on their surface. We may expect such indications to be peculiarly manifest in countries where the subterr~nean force has been in activity within comparatively modern ttmes, and it is there that the hypothesis of paroxysmal elevations, and the instantaneous rise of mountain-chains, should first have been put to the test, before it was hastily embraced by a certain school of geologists. . West Indian Archipelago.-According to the sketch giVen by Maclure of the geology of the Leeward Islandst, the • See above, p. 113. t Quart. J OUI'lh of Sci., vol. v. P• 31 l, Ch.X.] EAST INDIAN ARCHIPELAGO. 133 western range consists in great part of formations of the most modern period. It will be remembered, that many parts of this region have been subject to violent earthquakes; that in St. Vincent's and Guadaloupe there are active volcanos, and in some of the other islands boiling springs and solfataras. In St. Eustatia, there is a marine deposit, estimated at 1500 feet in thickness, consisting of coral limestone alternating with beds of shells, of which the species are, according to Maclure, the same as those now found in the sea. These strata dip to the south-west at an angle of about 45°, and both rest upon, and are covered by, cinders, pumice, and volcanic substances. Part of the madreporic rock has been converted into silex and calcedony, and is, in some parts, associated with crystalline gypsum. Alternations of coralline formations with prismatic lava and different volcanic substances also occur in Dominica and St. Christopher's, and the American naturalist remarks, that as every lava-current which runs into the sea in this archipelago is liable to be covered with corals and shells, and these again with lava, we may suppose an indefinite repetition of such alternations to constitute the foundation of each isle. "\'Ve do not question the accuracy of the opinion, that the fossil shells and corals of these formations are of recent species, for there are specimens of limestone in the Museum of the Jardin du Roi at Paris, from the Antilles, in which the imbedded shells are all or nearly all identical with those now living. Part of this limestone is soft, but some of the specimens are very compact and crystalline, and contain only the casts of shells. Of 30 species examined by M. Deshayes from this rock 28 were decidedly recent. Hondums.-Shells sent from some of the recent strata of Jamaica, and many from the nearest adjoining continent of the Honduras, may be seen in the British Museum, and are identified with species now living in theW est Indian seas. Ea.~t Indian Archipelago.-V\' e have seen that the Indian ocean is one of the principal theatres of volcanic disturbance. We expect, therefore) that future researches in this quarter of |