The only way to examine the living animal is to seize the little fragment of rock, or the shell to which the mysterious creature is fastened, at the very moment that it appears near the surface, and to dip it, if possible, without exposing it to the air, immediately into a vessel with salt-water, which you hold ready for the purpose. At first, there is nothing to be seen but a vague, indistinct mass of grayish substance. You suspend the animal and its tiny abode by a string in the middle of the glass globe, and carry it to a dark place; for the coral will not display its beautiful form and colors in the gleaming light of the day. It takes hours, often, before the obstinate little creature condescends to give a sign of life. At last the club-shaped extremity of the dingy red substance begins to wrinkle up into little rings here and there. Looking now with a magnifying-glass you perceive with joy, that the eight star-shaped indentations assume a white tinge, and the red grows every moment to a more lively hue. The lines widen, and soon the whole resembles a beautiful flower of eight leaves. We have seen that those wondrous little animals in length of time have built mountains to a height of fifteen thousand feet. The coral islands and reefs are but just above the surface of the water, except in cases where they have been lifted by earthquakes or other internal action, after the little architect of the sea had done his work. Many of these coral islands are of circular form, with an opening which will admit the passage of boats, and sometimes of ships. The waves break on the outer edge with that long, steady swell peculiar to the Pacific, but on the inside the water is as calm and peaceful as that of a mountain lagoon. Sometimes the coral reefs have been formed around the volcanic islands so as to encircle them completely, except at a single opening. In such cases, they make excellent harbors between the reef and the island: the harbor of Tahiti is a splendid specimen of this kind of work. The reef surrounds the island in such a way as to make a lagoon of still water, like the moat around a castle. The entrance is deep, and sufficiently wide to admit ships of every size. On many of the volcanic islands there are caverns, some of them of considerable size, and often of great depth. Runaway sailors frequently hide in these caverns, and they are also resorted to by the natives in times of warfare. There is a cavern in the Island of Hoonga, one of the Tonga Islands, which has a romantic history from the use that was made of it by the man who discovered it. [Sidenote: AQUATIC SKILL OF THE FEEJEEANS.]