The countries of the world : being a popular description of the various continents, islands, rivers, seas, and peoples of the globe . t theisland is made up of living polypes and their limy habitations, and the brokendebris tossed up by the breakers. New, how are such islands formed? To understandthe theory which is usually accepted, it is necessary to explain first the salient facts THE CORAL ISLAXDS-UOW FORMED. 9 which have bjen ascertained regarding the conditions under which the coral animal coral animals cannot live even for short periods exposed to the sun; accordingly theyneve
The countries of the world : being a popular description of the various continents, islands, rivers, seas, and peoples of the globe . t theisland is made up of living polypes and their limy habitations, and the brokendebris tossed up by the breakers. New, how are such islands formed? To understandthe theory which is usually accepted, it is necessary to explain first the salient facts THE CORAL ISLAXDS-UOW FORMED. 9 which have bjen ascertained regarding the conditions under which the coral animal coral animals cannot live even for short periods exposed to the sun; accordingly theynever raise their dwellings above the surface, or are found higher up than low-water is therefore clear that the coral islands could not have been raised above the level of thesea by the efforts of their builders. The agency which accomplishes this consists of the tear off great fragments of living coral from the reefs below water, toss them upon its surface until the mass is raised abov-e the surface, aud the detached fragmentsunited by the percolation amongst them of water charged with carbonate of lime. It is,. VIEW 01 JiOBABOKA, ONE OF THE COKAL ISLANDS (SHOWING FRIXGINO EEEFS). however, evident that the same force which has piled up the island in this manner couldalso destroy it by again attacking and tossing the torn off fragments to the another agency comes in force: this is the vital activity of the living coralswhich are alwa\s building upwards towards the surface from the seaward margin of thereef, and this prevents the sea from destroying the debris reared island which it hasformed. This is, however, another peculiarity about the reef-building coral animals, whichmust be explained before the nature of the islands, which are formed of the hard portionsof their bodies, can be understood. They must live under the water, but at the same timethey are creatures of shoals, and cannot exist at greater depths than some 15 to 30fathoms. It follows fro
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Keywords: ., bookcentury180, bookdecade1870, bookpublisherlondon, bookyear1876
