4 adjectives to describe atolls

Although the South Seas constitute the last fortress of romance, and a mention of the coral atolls immediately conjures up a vision of palms and rice-white beaches, the sensitive person senses the dark and bloody past when the wizard men were the rulers, and death stalked in the palm groves.

It is, in fact, an elongated, almost linear atoll, with islands scattered along its sheltered margin.

That where you find, as you often do in the Pacific, a mere atoll, or circular reef of coral, with a shallow pond of smooth water in the centre, and deep sea round, that is a pretty sure sign that the mountain-top has sunk completely into the sea, and that the corals are going on building where its peak once was.

Would I go to the Dangerous Archipelago, those mystic atolls that sent to the Empress Eugénie that magnificent necklace of pearls she wore at the great ball at the Tuileries when the foolish Napoleon made up his mind to emulate his great namesake and make war?

4 adjectives to describe  atolls