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Show 204 ISLAND LIFE. (PAR'r II. ------------------- does not exceed fifty square miles. They are surrounded by reefs, some at a distance of thirty miles from the main group; and the discovery of a layer of earth with rema.ins of cedar-trees forty-eight feet below the pres<mt high-water mark shows that the islands have once been more extensive and probably included MAP OF BERMUDA AND THE A~!ERT CAN COAST. NoTE.-The light t!nt indicates sea less than 1.000 fathoms deep. The dark tmt ,. ,. more than 1,000 fathoms deep. The flgures show the depth in fathoms. the whole area now occupied by shoals and reefs.1 Immediately beyond these reefs, however, extends a very deep ocean, while about 450 miles distant in a south-east direction, tho deepest part 1 Nature, Vol. VI. p. 262, "Recent Observations in the BermudaR," l>y Mr. ,J. Matthew Jones. CllAl'. Xll.] BERi\1UDA. 255 of the North Atlantic is reached, where soundings of 3,825 and 3,875 fathoms have been obtained. It is clear therefore that these islands are typically oceanic. Soundings were taken by the Challenger in four different ~irections around Bermuda, and always showed a rapid deepenmg of the sea to about 2,500 fathoms. This was so remarkable that in his reports to the Admiralty, Captain Nares spoke of Bermuda as " a solitary peak rising abruptly from a base only 120 miles in diameter;" and in another place ;1s "an isolated peak rising abruptly from a very small base." These expressions show that Bermuda is looked upon as a typical example of an "oceanic peak" ; and on examining the series of official reports of the Challenger soundings, I can find no similar case, although some coasts, both of continents and islands, descend more abruptly. In order to show, therefore, what is the real character of this peak, I have drawn a section of it on a true scale N BERMUDA SECTION OF BERMUDA AND ADJACENT S!l ;~ · DO'!'TOM. 1.'he flgures Rhow the depth in rathmns at flfly-five miles north and forty-six miles south ot tho islnnd.s respectil'ely. s from the soundings taken in a north and south direction where the descent is steepest. It will be seen that the slope is on both sides very easy, being 1 in 16 on the south, and 1 in 19 on the north. The portion nearest the islands will slope more rapidly, perhaps reaching in places 1 in 10; but even this is not steeper than many country roads in hilly countries, while the remainder would .be a hardly perceptible slope. Although generally very low, some parts of these islands rise to 250 feet above the sea-level, consisting of various kinds of limestone rock, sometimes soft and friable, but often very hard and even crystalline. It consists of beds which sometimes dip as much as 30°, and exhibit besides great contortions, so that at first sight the islands appear to exhibit on a small scale the phenomena of a disturbed Palmozoic district. It has however long |