I observed that one which I kept in the cabin was slightly
phosphorescent in the dark.
ST. PAUL'S ROCKS.
In crossing the Atlantic we hove-to, during the morning of February
16th, 1832, close to the island of St. Paul's. This cluster of
rocks is situated in 0 degrees 58' north latitude, and 29 degrees
15' west longitude. It is 540 miles distant from the coast of
America, and 350 from the island of Fernando Noronha. The highest
point is only fifty feet above the level of the sea, and the entire
circumference is under three-quarters of a mile. This small point
rises abruptly out of the depths of the ocean. Its mineralogical
constitution is not simple; in some parts the rock is of a cherty,
in others of a feldspathic nature, including thin veins of
serpentine. It is a remarkable fact that all the many small
islands, lying far from any continent, in the Pacific, Indian, and
Atlantic Oceans, with the exception of the Seychelles and this
little point of rock, are, I believe, composed either of coral or
of erupted matter. The volcanic nature of these oceanic islands is
evidently an extension of that law, and the effect of those same
causes, whether chemical or mechanical, from which it results that
a vast majority of the volcanoes now in action stand either near
sea-coasts or as islands in the midst of the sea.
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