UNITED STATES OF NORTH AMERICA, a republic formed by the federal union of 31 sovereign states, with five territorial append ages. It occupies the middle portion of North America ; and extends between 25° and 49° N. lat , 67° and 125° W. long.; from tho Atlantic Ocean on the east to the Pacific Ocean on the west. It is bounded N. by British America, S.W. by the republic of Mexico, and S. by the Gulf of Mexico. The boundary lines between the United States and British America, and the United States and Mexico, are described under BraTran AMERICA and MEXICO. The greatest width of the United States from east to west is 2900 miles, the greatest length from north to south is 1730 miles. The entire area of the United Statca has been very differently estimated. As estimated by the United States authoritiea for the Census office in 1850, Remounted to 3,306,865 square miles. But a more elaborate dud careful estimate made by the United States Topographical Bureau,' January 1854, reduces the area to 2,936,166 square miles, and if to this be added the additional terri tory of 27,500 square miles, ceded by Mexico by treaty in July 1854, the total area at the present time will be 2,963,666 square miles. The population in 1850 was 23,191,876, or to a square mile : but this does not include the native Indians, who were estimated by the Indian Commissioner iu 1853 at 400,764. The table at the head of the following page shows at a glance the states and territories which are comprised in the Union, with the extent of each, the number and character of its population in 1850, and various other particulars.
The areas of several of the states and territories in thia table it will be found on comparison differs in some instances considerably, from those given under the respective titlea of the statea in this work. For that difference we are clear of responsibility. All the areas of the atates were given from the official reports published by the government of the United States. Those in the following table are given from the new computations made by the United Statea Topographical Bureau,' with a view to obtaining greater accuracy ; and just made public in the 'Statistical View of the United States,' drawn up and printed by order of Congress.
Surface, Coast Line, tte.—The physical geography of the United States has been given generally under AMERICA; and more particularly under the heads of the several states and territories as enumerated in the following table; of the rivers CoLuatnie ; MissIssirri; Missouer, &c.;
the ALLEGnANY, and Roma MouNTanes, S.:e.; the lakes ERIE; ONTARIO, &e. Here it will suffice to remark that this extensive region is natu rally divided into three parts, widely differing in their characteristic features, by the Allegheny and Rocky Mountain ranges :—in the centre the enormoua drainage basin of the Mississippi, and on either side of it the eastern and western sal-boards. There lea remarkable parallelism between the physical structure of this part of the northern continent of America and that part of the southern contained between the parallel of the head-watera of the southern afiluenta of the Amazonas and the parallel of the embouchure of the Rio de In Plata : the Rocky Mountains correspond to the Andes; the Allegheny range to the mountains of Brazil ; and both in the northern and southern continents the parallel mountain-systems are connected by a tract of undulating country of no great elevation, forming a watershed between river-syatema which flow respectively to the north and to the aouth. The total area of the United States, as already atated according to the revised calcula tions of Colonel Abert, of the United States Topographical Engineers, is 2,963,666 square miles, which he thus apportions :—Area of the Pacific Slope, or of the region watered by rivers falling into the Pacific, 793,702 square miles ; the Mississippi Valley, 1,217,562 square miles; and the region whose waters fall into the Atlantic, 952,602 square miles, of which 514,416 square miles belong to the Atlantic slope proper, 112,619 square miles to the Northern Lake region, and 325,537 square miles to the region whose waters fall into the Gulf of Mexico, east and west of the 3lississippi. The main shore line of the United States on the Atlantic coast amounts to 6861 statute miles, on the Pacific to 2281 miles., on the Gulf of Mexico to 3167 miles ; the Wand shore on the !Atlantic to 6323 miles, on the Pacific to 702 miles, and on the Gulf of Mexico to 2217 miles, giving a main shore line Of 12,609 miles, and an island shore-line of 9217 miles.