The ocean / By P. H. Gosse.

  • Gosse, Philip Henry, 1810-1888.
Date:
[pref. 1845]
Catalogue details

Licence: Public Domain Mark

Credit: The ocean / By P. H. Gosse. Source: Wellcome Collection.

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    raised on the points of the reef, which, being com- monly tufted with cocoa-nut trees, is perceptible as far off as the island itself, and forms a most con- venient land-mark. Notwithstanding that the highest point of these narrow islets is rarely more than a yard above the tide, it is a remarkable fact that fresh water is fre- quently found in them. It is probable that the coral rock acts as a filter, allowing the sea-water to perco- late through its porous substance, but excluding all its saline particles held in solution. Though I have described the two parts of a Coral Island, or Atoll, as it is called, as distinct, yet the difference is only in appearance; the foundation on every side is the same, a coral reef rising to the sur- face ; but the side most exposed to the action of the waves driven in by the trade-winds, is invariably the first to be projected, and attains a higher elevation than the leeward side. Neither must it be supposed that the belt to windward is always continuous, though the interruptions are comparatively few. A close inspection will likewise show that the outline of the whole reef possesses much less regularity of form than its aspect from a distance indicated. The form, however, is invariably a more or less close approach to a circle. Sometimes the land is continu- ous through the whole circumference, with the ex- ception of a channel or two into the lagoon, which presents the appearance of a circular pond writh a verdant border surrounding it; again another atoll will be found which has brought its ring of reef scarcely to the surface, exposing, perhaps, a single