volume of her manufacturing and commercial interests. Its manufactories include foundries, blast-furnaces, copper-smelting works, locomotive and car-works, shipyards, iron-bridge works, safe, furniture, automobile and stove-factories and some of the largest tobacco and cigar-factories in the United States.
The city is the seat of the United States district and circuit courts of eastern Michigan. It has a law-library, an extensive public library, besides the libraries of the Masonic lodges, the trades-union council and the museum of art. It has many hospitals and philanthropic institutions, and is noted for the large number of fine churches and its well-equipped public-schools. There are more than 70 school-buildings, besides three high-schools, and the expenditure for public instruction exceeds a million dollars annually. Here also are the Detroit (R. C.) College, medical schools, law-schools, etc. Detroit is an important railroad-center and is one of the five chief lake-ports.
Detroit is one of the oldest American cities. It came into the possession of the French in 1610, who built a fort here in 1701, called Pontchartrain. The British held it from 1763 till 1796, when it passed to the United States. In the War of 1812, Detroit was captured by Sir Isaac Brock and held by the British for about a year. In 1824 the city was incorporated; from 1805 to 1837 it was the capital of Michigan Territory, and for the following ten years the capital of the state. After 1847 Lansing became the state capital. Adjacent to the city and commanding it and the approaches to the river is Fort Wayne, with extensive fortifications. Population, 465,766.
Detroit River, the name given to the strait through which the waters of Lake St. Clair and of the upper lakes flow into Lake Erie. It is about 20 miles long, and deep enough to float the largest vessels.
Deucalion (dū-kā′li-on), the hero of the Greek story of the flood. He was the son of Prometheus and the husband of Pyrrha. When Zeus had decided to destroy the race of men by a flood, Deucalion built an ark or ship, in which he and his wife floated during the nine days' flood which drowned all the other people of Greece. On the going down of the waters, the ark rested on Mount Parnassus. To repeople the world, Deucalion and Pyrrha were told by the goddess Themis to throw behind them the bones of their mother. This they did with the stones of mother-earth, and from those thrown by Deucalion, so the story goes, sprang up men, and from those thrown by Pyrrha sprang up women.
Development of Animal Life. The building of an animal's body is the most wonderful thing in all nature. An insect, a fish or a bird begins its development as an egg, and, as the construction of the body goes on, each tissue and each organ are formed anew out of the material contained within the egg. After three weeks' incubation of the hen's egg, for example, the young chick steps into the world with heart, brain, eyes and other organs all formed—a remarkable transformation. Frogs' eggs, laid in the water, undergo similar changes without any care from the parent; tadpoles hatch from them, and in due course of time these tadpoles grow into frogs, with a different kind of body. The hen's egg is large, because there is a large quantity of food-yolk stored up for the use of the growing chick; the frog's egg is smaller, because it contains less yolk; and some eggs—for example, those of starfishes—are smaller than pin-heads. The true starting-point of the chick is a microscopic cell within the egg; and, when we look to other animals, we find that all of them, no matter how complex, start in the condition of a single microscopic cell and that, between that simple state and the fully formed animal, which is complex, there are many steps. Therefore, the adult stage of any animal represents the last step in a long series of modifications. If we could only follow the changes, step by step, we should have a means of understanding all about the construction of animals and their past history. Tracing the stages by which cells emerge into tissues, tissues into organs and how the organs by combination build the body is called embryology or development. It is an important fact to keep before us that the rudiment of all life is a cell. (See Cell-Doctrine.) If we look upon cells as the bricks of organic architecture, the starting-point of a many-celled animal is a single brick; but, inasmuch as each egg needs to be fertilized before developing—just as a plant-ovule must be fertilized by pollen before it becomes a seed—the single brick is a compound one, made of material derived from each parent. The development of all animals is remarkably alike; from the single cell there come, by division, many cells; these continue to feed on the yolk, to grow and divide; and thereby a large number of cells arises. These cells arrange themselves into definite layers, from which all parts of the body are formed.
The earlier view of development was that the animal existed already formed within the egg, but was exceedingly minute, and that development consisted in the expansion or growth of this animal in miniature. But William Harvey (1598-1657) and Caspar F. Wolff (1733-94) showed the falsity of this view. The latter especially in 1759 showed (in Theoria Generationis) the true nature of development to consist in a real becoming or gradual formation, step by step, of the organs and the animal's
