IOWA, a State in the North Central Division of the North American Union; bounded by Wisconsin, Illinois, Missouri, Nebraska, South Dakota, and Minnesota; admitted to the Union, Dec. 28, 1846; number of counties, 99; capital, Des Moines; area, 56,025 square miles; pop. (1890) 1,911,896; (1900) 2,231,853; (1910) 2,224,771; (1920) 2,404,021.
Topography.—The surface of the State is generally level, with a gentle rise to ward the N. The highest elevation is near Spirit Lake, in Dickinson co., 1,694 feet. The center of the State forms a watershed between the Mississippi and the Missouri. There are no hills of con sequence, the entire surface being. a pla teau, and whenever irregularities occur, they are depressions below the general level. There arc steep bluffs along the river banks, caused by the wearing away of the drift and rocks by the water. The State is covered with prairie land, with no swamps or natural forests. The water system is divided into two parts, those rivers flowing into the Mississippi in the E., and those flowing into the Missouri in the W. Among the former are the Upper Iowa, Turkey, Maquoketa, Wapsipinicon, Cedar, Iowa, Skunk, Des Moines, and Boone, while the Missouri system includes the Chariton, Grand Platte, Nodaway, Nishnabotna, Boyer, Maple, Little Sioux, Rock, and Floyd rivers. The Big Sioux river forms most of the W. boundary. There are many small and beautiful lakes, the largest be ing Spirit Lake, and the Okoboji Lakes, in Dickinson co.
Geology.—The State presents 20 dis tinct geological formations. The N. part belongs to the drift deposits of Minnesota. Lower down the Lower Silurian is prominent, with Potsdam sandstone, lower magnesium limestone, and St. Peter's sandstone. The Upper Silurian is represented by the Niagara and Le Clair limestone, and the Devon ian by the Hamilton and Chemung car boniferous limestones.
Mineralogy.—The Illinois coal field extends over an area of 20,000 square miles in this State, and lead is found in Galena limestone near Dubuque. The coal production of the State in 1918 was 8,240,000 tons, which was 725,000 tons less than the production of lfq7.
The other mineral products are mineral waters, cement, gypsum, sand and gravel. The value of the cement produced in 1916 was $6,870,863. The total value of the mineral production in that year was $39,336,372.
Soi/.—The soil generally is a soft black loam, formed directly through deposits of the Quaternary age, and varies from 1 to 100 feet in depth. The soil is easily worked, free from stones and sturnps, and of almost inexhaustible fer tility. The soil of the prairies is a diluvial drift, while the river beds fur nish a light alluvial deposit. The prin cipal natural trees are several varieties of oak, hickory, elm, black walnut, lin den, cottonwood, maple, cedar, slippery elm, butternut, sycamore, ash, pine, and box-elder.
Agrieulture.—The fertility of the soil and the ease with which it may be worked present special advantages for agricul tural pursuits. Among native fruits are the plum, crabapple, grape, cherry, blackberry, gooseberry, strawberry, and raspberry, while the wild prairie grass is used for pasturage and for hay. The production and value of the principal crops in 1919 was as follows: corn, 416,000,000 bushels, valued at $499,200, 000; oats, 196,182,000 bushels, valued at $125,556,000; wheat, 23,675,000 bushels, valued at $47,350,000; hay, 5,181,000 tons, valued at $90,149,000; potatoes, 4,945,000 bushels, valued at $9,494,000.
Manufactures.—There were in 1914 5,614 manufacturing establishments in the State, with 630.13 wage earners. The capital invested amounted to $233, 127,000; and the wages paid to $39,816, 000. The value of the materials used amounted to $205,451,000, and the value of the finished product to $310,750,000. The principal manufacturing places are Sioux City, noted for its flour mills; Cedar Rapids, Davenport, Dubuque, and Des Moines. The chief articles of manu facture include dairy products, agricul tural implements, confectionery, cloth ing, flour and grist, lumber, saddlery and harness, packed meat, and to bacco.