The whole story, if ever it be told at length, will be intricate; but we believe that a general persuasion that land-measurements ought to be fixed by law and by reference to some one carefully preserved standard is much more modern than most people think. Real accuracy and the establishment of a measure that is to be common to the whole realm first emerge in connexion with the measurement of cloth and such like. There is a delightful passage in the old Scotch laws which tells us that the ell ought to contain 37 inches meted by the thumbs of three men, ‘þat is to say, a mekill man and a man of messurabill statur and of a lytill man[1243].’ We have somewhere read that in Germany, if a perch of fifteen feet was to be manufactured, the first fifteen people who chanced to come out of church contributed each a foot towards the construction of the standard. At an early time, however, men were trying to find some class of small things which were of a fairly invariable length and hit upon barley-corns. This seems to have happened in England before the Norman Conquest[1244]. Instead of taking the ‘thoume’ of ‘a man of messurabill statur’ for your inch, you are to take three barley-corns, ‘iii bear cornys gud and chosyn but tayllis (i.e. without the tails)’[1245]. But the twelfth century was drawing to an end before any decisive step was taken to secure uniformity even in the measurement of cloth. In Richard I.’s day guardians of weights and measures are to be appointed in every county, city and borough; they are to keep iron ulnae[1246]. At this time or a little later these ulnae, ells or cloth-yards were being delivered out by a royal officer to all who might require them, and that officer had the custody of the ultimate standards[1247]. We may doubt whether the laws which require in general terms that there shall be one measure throughout the realm had measures of land in view[1248]. A common standard is not nearly as necessary in this case as it is in the case of cloth. Even in our own day men do not buy land by the acre or the perch in the same sense as that in which they buy cloth or cotton by the yard. Very rarely will anyone name a price for a rood and leave it to the other bargainer to decide which out of many roods shall be included in the sale. Nevertheless, the distribution of iron ulnae was important. An equation was established between the cloth measure and the land measure: five-and-a-half ulnae or cloth-yards make one royal perch. After this we soon find that land is occasionally measured by the iron ulna of the king[1249].
Superficial measure.
The scheme of computation that we know as ‘superficial measure’ was long in making itself part of the mental furniture of the ordinary man. Such terms as ‘square rod’ and ‘square mile’ were not current, nor such equations as that which tells us how 144 square inches make a square foot. Whatever may have been the attainments of some cloistered mathematicians, the man of business did not suppose that he could talk of size without talking of shape, and indeed a set of terms which speak of shapeless size is not very useful until men have enough of geometry and trigonometry to measure spaces that are not rectangular parallelograms. The enlightened people of the thirteenth century can say that if an acre is x perches long it is y perches wide[1250]. They can compare the size of spaces if all the lines be straight and all the angles right; and for them an acre is no longer of necessity ten times as long as it is broad. But they will not tell us (and they do not think) that an acre contains z ‘square perches.’ This is of some importance to students of Domesday Book. Very often the size of a tract of land is indicated by the length of two lines:—The wood or the pasture is x leagues (furlongs, perches, feet) in length and y in breadth. Now, to say the least, we are hasty if we treat this as a statement which gives us size without shape. It is not all one to say that a wood is a league long and a league wide and to say that it is two leagues long and half a league wide. The jurors are not speaking of superficial content, they are speaking of length and breadth, and they are either giving us the extreme diameters of the irregularly shaped woods and pastures, or (and this seems more probable) they are making rough estimates of mean diameters. If we go back to an earlier time, the less we think of ‘superficial measure’ the better[1251].
The modern system.
Let us recall the main features of our modern system, giving them the names that they bore in medieval Latin.
Linear Measure.
12 inches (pollices)=1 foot (pes); 3 feet=1 yard (ulna); 5·5 yards=1 rod, pole, perch (virga, pertica, perca); 40 perches=1 furlong (quarentina); 8 furlongs=1 mile (mille); 12 furlongs=1 leuua, leuca, leuga (league)[1252].
Superficial Measure.
144 square inches=1 square foot; 9 square feet=1 square yard; 30·25 square yards=1 square perch; 40 square perches=1 rood; 4 roods=1 acre[1253].
In the thirteenth century these outlines are already drawn; but, as we have seen, if we are to breathe the spirit of the time, we ought to say (while admitting that acres may be variously shaped) that the normal acre is 4 perches in width and 40 perches (=1 furlong) in length. The only other space that we need consider is the quarter of an acre, our rood. That ought to be 1 perch in width and 1 furlong (=40 perches) in length. The breadth of the acre is still known to all Englishmen, for it is the distance between the wickets.