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Barrier Reefs.]

the deep waves of the ocean, it is particularly well adapted to the purposes of a coasting trade. The reader will be struck with the analogy which this arm of the sea presents to one in nearly the same latitude of the northern hemisphere. The Gulph of Florida is formed by the coast of America on the west, and by a great mass of islands and shoals on the east; which shoals are also of coral.

On the outside of the barrier, the sea appears to be generally unfathomable; but within, and amongst the reefs, there are soundings every where. Nor is the depth very unequal, where the bottom is sandy; but like the breadth of the reefs and the arm they inclose, it diminishes as we advance northward, from 60 to 48, to 35, and to 30 fathoms near our opening; and to 20 at Cape Tribulation. The further to leeward, the shallower the water, seems to be a law amongst coral reefs.

There is some variation in the tide in different parts of the barrier, but the most general rise is about two fathoms; abreast of the Northumberland Islands, however, where the flood from the south-east seems to meet that from the northward, it is three fathoms, and perhaps more. The time of high water there, and also at the eastern Cumberland Islands, is eleven hours after the moon's passage; but it probably accelerates north-westward, to the opening, and then retards further on: at Endeavour River, captain Cook, found it to be high water an hour and a half earlier than is above given.

It has been said, that the width of the opening by which we got out to sea, is uncertain; it is undoubtedly four, and possibly more leagues, but there are many small, unconnected banks in it. To a ship desiring access to any part of the coast, south of Endeavour River, I should certainly recommend her to enter the inclosed sea by the way of Break-sea Spit, if able to choose her own route; but the question is, whether a ship driven by stress of weather, or by accident, to seek the coast, might steer for the opening with a fair prospect of passing through in safety? I certainly think she might; with the precaution of not attempting the passage late in the day. The