Coral Reefs
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第97章

In front of the eastern MOSQUITO coast, there are between latitude 12 deg and 16 deg some extensive banks (already mentioned, page 148), with high islands rising from their centres; and there are other banks wholly submerged, both of which kinds of banks are bordered, near their windward margins, by crescent-shaped coral-reefs. But it can hardly be doubted, as was observed in the preliminary remarks, that these banks owe their origin, like the great bank extending from the Mosquito promontory, almost entirely to the accumulation of sediment, and not to the growth of corals; hence I have not coloured them.

CAYMAN ISLAND: this island appears in the charts to be fringed; and Captain B. Allen informs me that the reefs extend about a mile from the shore, and have only from five to twelve feet water within them; coloured red.--JAMAICA: judging from the charts, about fifteen miles of the S.E. extremity, and about twice that length on the S.W. extremity, and some portions on the S. side near Kingston and Port Royal, are regularly fringed, and therefore are coloured red. From the plans of some harbours on the N. side of Jamaica, parts of the coast appear to be fringed; but as these are not represented in the charts of the whole island, I have not coloured them.--ST. DOMINGO: I have not been able to obtain sufficient information, either from plans of the harbours, or from general charts, to enable me to colour any part of the coast, except sixty miles from Port de Plata westward, which seems very regularly fringed; many other parts, however, of the coast are probably fringed, especially towards the eastern end of the island.--PUERTO RICO: considerable portions of the southern, western, and eastern coasts, and some parts of the northern coast, appear in the charts to be fringed; coloured red.--Some miles in length of the southern side of the Island of ST. THOMAS is fringed; most of the VIRGIN GORDA Islands, as I am informed by Mr. Schomburgk, are fringed; the shores of ANEGADA, as well as the bank on which it stands, are likewise fringed; these islands have been coloured red. The greater part of the southern side of SANTA CRUZ appears in the Danish survey to be fringed (see also Prof. Hovey's account of this island, in "Silliman's Journal," volume xxxv., page 74); the reefs extend along the shore for a considerable space, and project rather more than a mile; the depth within the reef is three fathoms; coloured red.--The ANTILLES, as remarked by Von Buch ("Descrip.

Iles Canaries," page 494), may be divided into two linear groups, the western row being volcanic, and the eastern of modern calcareous origin; my information is very defective on the whole group. Of the eastern islands, BARBUDA and the western coasts of ANTIGUA and MARIAGALANTE appear to be fringed: this is also the case with BARBADOES, as I have been informed by a resident; these islands are coloured red. On the shores of the Western Antilles, of volcanic origin, very few coral-reefs appear to exist. The island of MARTINIQUE, of which there are beautifully executed French charts, on a very large scale, alone presents any appearance worthy of special notice. The south-western, southern, and eastern coasts, together forming about half the circumference of the island, are skirted by very irregular banks, projecting generally rather less than a mile from the shore, and lying from two to five fathoms submerged. In front of almost every valley, they are breached by narrow, crooked, steep-sided passages.