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Show 282 TRLAND LrFr•:. [I'Afi'l' lT. ~ )'; ~ ~ ~ v. 0 ~ 0 p.. ~ ~ £-< 0 :,-, ~ 0 ffi I z I 8 0 8... ~ ~... «< t..i.l p £ ~ til r"."..' 0 p.. ~ g 0 :S .;g .s ~ Ql :!'::1 ..... 0 Jl ~ '0 ::: 0 ~ <Jl "3' eo "" Ql ..c:l f:-< ~ :B ~ 0 0 0 ....; l':l ell ~ v""' ' .... 0 .."c:'l e. '0 rn i:: 0 ~ ~ ..... ..c:l ~0 v ..c:l H (liAP. XI\',) ST. Il ELENA. 283 northern rim forms tl1e highest nnd reulml ri!lge of the island. Many other hms and peaks, however, are more Umn two thousand feet high, and a consiclerable portion of the surface consists of a, rugged plateau, having an elevation of about fifteen hundred to two thousand feet. Everything indicates that St. Helena is an isolated volcanic mass built up from the depths of the ocean. Mr. Wolln.ston remarks: "There are the strongest reasons for 'believing that the area of St. Helena was never ve1·y much larger than it is at present-the comparatively shallow sea-sounding!-; within about a mile and a half from the shore revealing an abruptly defined ledge, beyond which no bottom is reached at n. depth of 250 fa,thoms; so that the original basaltic mass, which was gradually piled up by means of successive eruptions from beneath the ocean, would appear to have its limit definitely marked out by this suddenly-terminating submarine cliff-the space between it and tho existing coast-line being reasonably referred to that slow process of disintegration by which the island has been reduced, through the eroding action of the elements, to its present dimensions." If we add to this that between the island and tho coast of Africa, in a south-easterly clirection, is a ·profound oceanic gulf known to reach a depth of 2,860 fathoms, or 17,160 feet, while an equally deep, or perhaps deeper, ocean, extends to the west and south-west, we shall be satisfied that St. Helena is a true oceanic island, and that it owes none of its peculiarities to a former union with any continent or other distant lnn<l. Change ~f!ected by E'lt?·opean occnpation.- When first discoverecl, 378 year;:, ago, St. Helena was densely covered with a luxuriant forest vegetation, the trees overhanging the seawanl precipices and covering every part of the surface with an evergreen mantle. This indigenous vegetation has been almost wholly destroyed; :md although an immense number of foreign plants have been introduced, and have more or less completely established themselves, yet the general aspect of the island is now so barren and forbidding that some persons find it difficult to believe that it was once all green and fertile. The cause of the change is, however, very easily explained. The rich soil fonHell by t1ecomposed volcanic rock aml vegetable deposits |