The ancient elements of land measure.
This system has been generated by the corelation of cloth-measures and land-measures. If we are going back to remote times, we must expel the cloth-measures as intruders. What then is left is very simple; it is this:—the human foot, a day’s ploughing and a measuring stick which mediates between feet and acres. That stick has had many names. Our arithmetic books preserve three, ‘rod, pole or perch’; it has also been known as a gād or goad and a lug: but probably its oldest name is yard (gyrd). It is of some importance that we should perceive that our modern yard of three feet is not one of the very ancient land-measures. It is a ‘cloth-yard’ not a land-yard. In medieval documents the Latin name for it is ulna[1254], and probably the oldest English name for it is eln, elle, ell. There seems to have been a shifting of names. The measuring rod that was used for land had so many names, such as perch, rod, pole, goad, lug, that it could afford, if we may so speak, to dispense with the additional name of yard, which therefore might stand for the much shorter rod that was used by the clothiers. However, even in our own century men have been speaking of ‘yards of land’ in a manner which implies that at one time a yard, when mentioned in this context, was the same thing as the perch. When they have spoken of a ‘yard of land’ they have meant sometimes a quarter of an acre (our rood) and sometimes a much larger space. In 1820 a ‘yard of land’ means, we are told, a quarter of an acre in Wiltshire, while in Buckinghamshire it stands for a tract which varies from 28 to 40 acres[1255]. This last application of the term we shall consider by and by. A yard of land or rood of land (rood and rod are all one) is a quarter of an acre, because an acre is four rods or ‘yards’ or perches in width, and, when an acre is to be divided, it is always, and for a very good reason, divided by lines parallel to its long sides. So though the rood or yard of land may in course of time take other shapes and even become a shapeless size, it ought to be a rod or ‘yard’ in width and forty rods or one furlong in length.
The German acre.
So we start with the human foot, the day’s ploughing and a rod. How much borrowing there has been in this matter by race from race is an obscure question. For example, the mediation of a rod between the foot and the day’s work is common to the Roman and the Germanic systems. Here the similarity ends, and the vast differences which begin seem to have exceedingly deep roots. We can not be content with saying that the Roman puts two oxen in the plough and therefore draws short furrows, whereas the German puts eight oxen and draws long furrows. There seems to be a radical disagreement between them as to what a plough should be and what a plough should do[1256]. To these matters we can make but the slightest reference, nor dare we touch the problems of Celtic history. Somehow or another the Germans come to the rule that generally an acre or day’s work should be four rods wide and, if possible, about forty rods long[1257].
English acres.
It is very probable that in England this rule prevailed at a remote time. Throughout the middle ages and on to our own day there have been many ‘acres’ in England which swerved markedly from what had become the statutory type, and in some cases a pattern divergent from the statutory pattern became ‘customary’ in a district. But apparently these customary acres commonly agree with the royal standard in involving the equation: 1 acre = 4 perches x 40 perches[1258]. In Domesday Book and thence onwards the common Latin for furlong is quarentina, and this tells us of furrows that are forty perches long. It is when we ask for the number of feet in a perch that we begin to get various answers, and very various they are. The statutory number, the ugly 16·5, looks like a compromise[1259] between 15 and 18, both of which numbers seem to have been common in England and elsewhere. This is the royal equation in the thirteenth century; it has been found near the middle of the twelfth[1260]; more at present we cannot say. Small acres.Short perches and small acres have been very common in the south of England. In 1820 some information about the customary acre was collected[1261]:—In Bedfordshire it was ‘sometimes 2 roods.’ In Dorsetshire ‘generally 134 [instead of 160] perches.’ In Hampshire, ‘from 107 to 120 perches, but sometimes 180,’ In Herefordshire, ‘two-thirds of a statute acre,’ but ‘of wood, an acre and three-fifths or 256 perches.’ In Worcestershire, ‘sometimes 132 or 141 perches.’ In Sussex, ‘107, 110, 120, 130 or 212 perches’; ‘short acre, 100 or 120 perches’; ‘forest acre, 180 perches,’ Then as to rods, the ‘lug or goad’ of Dorsetshire had 15 ft. 1 in.; in Hertfordshire, 20 feet; in Wiltshire, 15 or 161⁄2 or 18. The wide prevalence of rods of 15 feet can not be doubted, and it seems possible that rods with as few as 12 feet have been in use[1262]. An acre raised from a 12 foot rod would, if feet were invariable, be little more than half our modern statute acre. Nowhere do we see any sure trace of a rod so short as the Roman pertica of ten pedes, though the scribes of the land-books will give the name pertica to the English gyrd[1263].
Large acres.
In northern districts the ‘customary’ acre grows larger. In Lincolnshire it is said to be ‘5 roods, particularly for copyhold land’; but small acres were known there also[1264]. In Staffordshire, ‘nearly 21⁄4 acres.’ In Cheshire, ‘formerly and still in some places 10,240 square yards’ (pointing to a rod of 24 feet). In Westmoreland, ‘6760 square yards’ (pointing to a rod of 191⁄2 feet), also the so-called ‘Irish acre’ of 7840 square yards (pointing to a rod of 21 feet). There is much evidence that rods of 20 and 21 feet were often used in Yorkshire and Derbyshire. Rods of 18, 191⁄2, 21, 221⁄2 and 24 feet were known in Lancashire. A writer of the thirteenth century speaks as if rods of 16, 18, 20, 22 and 24 feet were in common use, and mentions none shorter[1265]. As just said, the Irish plantation acre was founded on a rod of 21 feet. The Scotch acre also is larger than the English; it would contain about 6150·4 instead of 4840 of our square yards; it is formed from a rod of 6 Scotch ells. On the other hand, the acres which have prevailed in Wales seem to be small; one type had 4320 of our square yards, another 3240
Anglo-Saxon rods and acres.
There has been variety enough. Even if the limits of variation are given by rods of 12 and 24 feet, this will enable one acre to be four times as large as another. Whether before the twelfth century there was anything that we ought to call a standard rod, a royal rod for all England, must be very doubtful. In royal and other land-books references are made to furlongs, to acre-breadths, to yards or rods or perches, and to feet as to known measures of length[1266], but whether a kingly gift is always measured by a kingly rod we do not know. The Carolingian emperors endeavoured to impose a rod upon their dominions; it seems to have been considerably shorter than our statute perch[1267]. In this province we need not expect many Norman novelties. We see from Domesday Book that the Frenchmen introduced the ancient Gallic arpentum[1268] as a measure for vineyards[1269]; but most of the vines were of their own planting, and the mere fact that they used this measure only for the vineyards seems to tell us that they were content with English rods and English acres[1270]. In Normandy the perches seem to have ranged upwards from 16 to 25 feet[1271]; so that 16·5 would not have hit the average. On the whole, our perch seems to speak of a king whose interests and estates lay in southern England and who struck a mean between 15 and 18. Whoever he was, we owe him no thanks for the ‘undecimal’ element that taints our system[1272].