Domain, Or Demesne,(mediaeval Lat. doma-nium, the dominion of the lord), in England, lands retained by the great landed proprietors for their own use; the terroe dominicales or demesne lands being occupied by the lord or dominus manorii, while the other or tenemental lands are distributed among the tenants. The demesne lands of the king, terroe dominicales regis, which were at an early period very large, and to which additions were made by forfeitures and otherwise, had been, at the time when Blackstone wrote, almost entirely alienated; but as a portion of them were not conveyed absolutely in fee, but upon long leases, they will revert to the crown upon the expiration of those leases. The principal importance of the royal demesne lands grows out of certain incidents that at an early period attached to the estate of the tenants of those lands. The tenure by which such estates were held is designated by old writers as ancient' demesne; and to some extent it still continues to exist. Strictly, lands so held were copyhold, and as such were excepted by the statute 12 Charles II., c. 24, by which military tenures were abolished.

One incident, showing that the tenure was originally a species of villenage, is that the lands do not pass by the common conveyances, but by surrender to the lord in the manner of copyhold estates, for certain uses mentioned in the surrender, and a new grant by the lord in pursuance thereof to the cestuy que use. - The public domain of the United States is almost beyond calculation. The original thirteen states embraced an area of 341,756 square miles. The whole territory conceded to the United States by the definitive treaty of peace of 1783 was 830,000 square miles. The concessions made by the states to the general government of lands claimed by them outside their respective limits constituted the nucleus of our public domain, which was afterward increased by the purchase of Louisiana from France and Florida from Spain, the annexation of Texas, the acquisitions from Mexico, and the purchase of Alaska from Russia, to a grand total of 2,912,784.74 square miles, or 1,864.382,223 acres, which has first or last belonged to and been subject to sale or other disposition by the government of the United States. For its sale the general system, which now for a long time has prevailed, is to cause it to be surveyed into townships six miles square, embracing 36 equal sections, and these subdivided into quarters, eighths, and sixteenths, and the lots sold at a uniform price of $1 25 an acre.

Full payment is in general required before giving title or possession; but preemption privileges to the extent of 160 acres are allowed to settlers, who on complying with the formalities prescribed by law may enter and make improvements. A homestead not exceeding 160 acres is given to actual settlers who enter under proper claim and actually occupy for five years. In addition to these liberal provisions for settlers, large quantities of land have been given as bounties for military services, and munificent donations made for various public purposes. The lands designated in the public surveys as swamp or overflowed lands, but a considerable portion of which are only nominally such, have been generally given to the states within which they lie; every sixteenth section in a township has been set apart for the support of common schools; large endowments in lands have been made for agricultural colleges and other institutions of learning, and still larger to the states or to private corporations for the construction of canals, railroads, and other public works. The general purpose of these grants is to facilitate settlement and advance the general prosperity, rather than to make the lands a source of revenue.

Rapid as has been the disposal of public lands, 1,307,115,448 acres still remained unsurveyed and 1,387,732,209 84 unsold and unappropriated in 1870, according to the estimate of the United States land office; but this is subject to large deductions when the grants for railroad lines are earned and located. - The term domain is applied variously in other countries; but in general it embraces, 1, the highways, harbors, fortifications, etc. (as to which see Eminent Domain); 2, the government palaces and other public buildings, gardens, forests, parks, crown jewels, etc.; 3, forfeited estates and other property which the government may dispose of for revenue; 4, the private estate of the monarch, which he may dispose of by will or otherwise, but which if not so disposed of will pass to his successor.