Coral
3 of the 7 encyclopedias on this shelf carry an entry for Coral. Both are reproduced below, so you can see where they agree and where they differ.
Aiton's Encyclopedia (1910)
a limy secretion of marine animals called polyps. These polyps are related to the sea anemone, the jelly fish, and to the fresh water hydra. There are numerous coral-producing species. Though called a skeleton, coral is produced on the outside of the animal for a shelter, or home in which to live. A piece of coral is usually the product of a large colony of polyps that bud or branch like trees. The coral of some species takes the form of a fan; of others that of a branching shrub or flower; or a mushroom; or a brain-like mass; or a bunch of moss. One might conclude readily that coral is a sort of limy moss or other vegetable growth; but in reality it is an animal production corresponding very closely to the shell of a snail. A coral mass consists of tubes in which the polyps find shelter. As the polyp extends, the tube in which it lives grows longer. The coral-producing polyps-they are not insects--appear to live on sea water. They require a temperature that never falls below 68 deg., a hard bottom to which to attach themselves, and sea water entirely free from mud or grit. No coral is found on the western coast of the two Americas. On their eastern coast it is confined to tropical waters extending from Florida to Brazil. Red corals, much prized for necklaces and other articles of ornament, are found in the waters of the Mediterranean. Beautiful coral comes from Japan. Coral is found sometimes in masses of extraordinary size. In the southern Pacific and Indian oceans it not infrequently forms reefs from a few yards to many miles in length. The great Barrier Reef, thirty miles off the northeastern coast of Australia, is of coral formation. It extends 1,300 miles along the coast, with a total area of nearly 100,000 square miles. The water between the reef and mainland is seldom less than 36 feet deep. The outer wall of the reef is usually vertical. It has not been surveyed with accuracy, but in places it has been found to extend nearly perpendicularly 1,700 feet below the surface of the water. The circular islands of the Pacific known as atolls are also of this nature; the reef taking the form of the circumference of a circle, inclosing a round lagoon within. It was supposed formerly that the lagoon marks the apex of an island which has gradually subsided, leaving a fringe of coral which the polyps have built up and up as the bottom sank, but this theory of subsidence is now in question. The reef corals are built on the plan of six or some multiple of six; that is to say, the tubes are six or twelve sided. The other group of fan corals is built on the plan of eight. See Australia ; Naples Vase coral. Eye coral. Reef coral. Sea anemone. Corals Sea-pen. Coral Coral, sectional view Common red coral
Collier's New Encyclopedia (1921)
the name applied to the calcareous stony structures secreted by many of the actinozoa, which form one of the divisions of the coelenterate zoöphytes, and also applied to the animals themselves. Two kinds of corals are distinguished by naturalists, sclerodermic and sclerobasic, or those in which the calcareous skeleton is developed in the walls of the body, as in the reef-building corals, and those in which (as in the red coral of commerce) the skeleton is external or cuticular. Reproduction takes place by ova, but chiefly by budding, the new individual re remaining in organic union with the old. The coral masses grow not merely by the multiplication of individuals, but by the increase in height of each of the latter, which, as they grow, become divided transversely by partitions. The animal, distended with ova, collapses on their discharge, and thus becomes too small for the cup which it formerly occupied; it cuts off the waste 1 CORAL 1. Organ pipe Coral-skeleton of colony with two living polyps. space by a horizontal layer of coral, and the repetition of this process gradually adds to the height of the mass. It is in this way that the coral reefs and islands, occurring in such abundance in the Pacific, the Indian Ocean, and the Red Sea, are built up. The coral of commerce is the production of various polyps, and is of different colors and internal structure. The red, pink, and black sorts are the most highly prized. The red coral has a branching shrublike form, and, as well as other sorts, is found abundantly in the Mediterranean. The coral fishery, as it is called, is carried on in various parts of the Mediterranean, the principal localities being the S. W. coast of Cor 2 3 2. True or stony Coral. 3. Cup Coral. sica, where the finest quality is found, the coast of south Italy, and the N. coast of Africa (Algeria and Tunis). The raw coral is wrought chiefly in Leghorn, Genoa, and Naples.
An Encyclopaedia of Occultism (1920)
It stops bleeding, preserves houses from thunder, and children from evil spirits, goblins, and sorceresses. Crollius It also strengthens digestion, and if taken in powder as soon as the child is born, preserves it from epilepsy.