1. Introduction
The first measures of land were seed-measures. They are found in every country; they become fixed in course of time as the idea of geometric measurement arises; they survive in name giving the peasant a concrete idea of the extent of his fields.
Then came the estimation of land by the amount of ploughing, or sometimes of hand-digging, that could be done in a day, and by the extent that could be cultivated with a pair of oxen. Then came a system of geometric measurement, fixing the former seed-units or labour-units by measures of length and breadth, and finally the abstract idea of superficial area. These different systems have succeeded one another everywhere and in all time.
1. Seed-units.—The land that could be sown with a certain measure of seed-corn, wheat being the usual standard: Fr. seterée, estrée, boisselée, &c.; It. moggio; Sp. fanega; G. scheffel; Nor. tunn-land. These names correspond to corn-measures.
2. Day’s hand-labour units.—The land that could be tilled with spade or hoe in a day: the ‘Daieswork,’ about 10 square rods; Fr. hommée, ouvrée—20 square rods of vineyard.
3. Day’s ploughing units.—L. jugerum; It. giornata; Fr. journal, arpent; G. morgen, joch, acker; Du. bouw; Hind. bigha; Ar. feddan; Ir. ardagh. All about an English acre more or less.
4. Oxgang units.—The land that a boor with a yoke of oxen could keep in husbandry; about 7 acres of arable, about 30 acres including wood and pasture:
Yard-land; Du. hoeve. A group of oxgangs, generally of four yoke, made a Ploughland; Prov. un mas de quatre couble, a four-yoke farm.
5. Geometric units.—First, units of a certain shape based on the customary length of the furrow: Rood, 40 rods by 1 rod broad; Fr. vergée, seillon. Then small units of a square rod, the rod being of customary length; with large units, usually groups of roods, vergées, &c. Four roods side by side make the English or the Norman acre. A rood square or square furlong is the ‘acreme’ or 10-acre field.
Legal units of land were usually abstract, of so many square rods or fathoms, independently of any customary shape.