The following, we think, may be considered an approximate estimate of the population of the United States, in 1850, classed according to their descent from the European colonists, previous to the American Revolution, also from immigration since 1790, from the people who inhabited the territories acquired by the United States (Louisiana, Texas, &c.), and from Africans: Descendants of the European colonists, previous to 1776: 14,280,885 Ditto of people of Louisiana, Texas, and other acquired territories: 1,000,000 Immigrants since 1790, and their descendants: 4,350,934 Descendants of Africans: 3,626,961 Total population: 23,258,760 It will be seen from the above, that the total number of immigrants arriving in the United States from 1790 to 1850, a period of 60 years, is estimated to have been 2,759,329—or an average of 45,988 annually for the whole period. It will be observed also that the estimated increase of these emigrants has been 1,590,405, making the total number added to the population of the United States since 1790, by foreign immigrants and their descendants, 4,350,934. Of these immigrants and their descendants, those from Ireland bear the largest proportion, probably more than one half of the whole, or say two and a half millions. Next to these the Germans are the most numerous. From the time that the first German settlers came to this country, in 1682, under the auspices of William Penn, there has been a steady influx of immigrants from Germany, principally to the Middle States; and of late years to the West. The density of population is a branch of the subject which naturally attracts the attention of the inquirer. Taking the thirty-one States together, their area is 1,485,870 square miles, and the average number of their inhabitants is 15.48 to the square mile. The total area of the United States is 3,280,000 square miles, and the average density of population is 7.22 to the square mile. From the location, climate, and productions, and the habits and pursuits of their inhabitants, the States of the Union may be properly arranged into the following groups: Divisions. Area in Population. Inhab. to sq. miles. sq. m. New Engl’d States (6) 63,226 2,727,597 43.07 Middle States, including 151,760 8,653,713 57.02 Maryland, Delaware and Ohio (6) Coast Planting States, 286,077 3,537,089 12.36 including South Carolina, Georgia, Florida, Alabama, Mississippi and Louisiana (6) Central Slave States: 308,210 5,168,000 16.75 Virginia, North Carolina, Tennessee, Kentucky, Missouri, Arkansas(6) Northwestern States: 250,000 2,735,000 10.92 Indiana, Illinois, Michigan, Wisconsin and Iowa (5) Texas 237,321 212,000 .89 California 188,982 165,000 .87