Rods, poles and perches

Michael Slater and Ian Saunders

In a deed between Thomas Armetstead younger and elder of 1633 concerning land transfer in Langcliffe the word ‘fall’ was noted in a description of a parcel of land; ‘All that one parcel of ground lying and being within the fields of Langcliffe aforesaid on a place called and known by the name of watelanndes alias whitelanndes containing by estimation 30 falles of ground...’ (Raistrick collection no. 744). Similarly ‘tenn falls of ground’ quoted in a Cowside (Langcliffe) deed of 1655. The Oxford English Dictionary and English Dialect Dictionary give the definitions of the word ‘fall’ as ‘The distance over which a measuring rod falls’ and ‘A linear measure consisting of the fortieth part of a furlong’; this makes it 5.5 yards which happens also to be the standardized length of a rod, pole or perch. The word ‘fawe’ has been heard used in the Dales to denote the length measurement the perch (Johnson, 2005). The Etymological Dictionary of the Scottish Language (1880) defines ‘fall’ as a measure nearly equal to an English perch or rod .... ‘of sex elnes lang’. Further enquiry into the meaning and uses of these words seemed to be of interest. What follows may leave some people bemused. It is not a clear story!

Quoted measurements of lengths and areas appertaining to land are often found in old deeds and wills. Most commonly the rod, pole, rood and acre are the units used for areas of parcels of land. Linear measurements are less commonly quoted, but the units ell, rod, pole and perch are well-known to those who went to school in the 1950s and before (but not used!). Confusingly the words rod and pole are used both for length and for area, but the context is usually sufficient to remove any doubt about what is meant. For example, in the sale of the manor of Langcliffe deed of 1591 between Nicholas Darcy of Northampton, Henry Billingsley of London and the yeomen of Winskill and Cowside (PC/LAC 13 Northallerton and TNA C54/1408 CP 3572) the land area is defined as ‘all which acres...shall conteyne the rate of fyve ells and a halfe to everie polle and one polle in breadthe and fortie polles in lengthe to everie roode..’ The similar deeds with various Langcliffe tenants have the same definition (C54/1419 and 1424 CP 3572). In the deed of 1593 between Nicholas Darcy of Northampton, Henry Billingsley of London and Richard Armitstead of Langcliffe (Raistrick collection no. 735) the land purchased ‘shall contain in measure by and after the rate of five ells and a half to every pole and a pole in breadth and forty poles in length to every rood....’ The word ell therefore is here equivalent to a yard. The English ell was 45 inches but the Scottish one was 37.2 inches.

Knotted ropes seem to have been the first method used to define distances and ancient examples have been found in Egyptian tombs, where representations of wooden rods also survive in the form of votive offerings. End caps for a measuring rod were found in a surveyor’s tomb at Pompeii, but the rod itself did not survive. The need for official standards of weights and measures was recognized in England in Anglo-Saxon times (a standard yard being kept at London and Winchester), but there was little local requirement for accurate measures (when a yardstick might have been used?). The Statute for Measuring Land (pre-1284) declares that 12 inches make a foot and three feet make a yard but the definition of an inch was based on three barley grains. The King’s iron bar was the rather inaccessible standard. Until the 1700s the acre was not a fixed area - it varied according to location in this country - and the old unit is now known as a customary acre as distinct from the later Statutory acre of 4840 square yards. Precisely known acreages were not usually required since fields and pasture lands were recognizable by names and boundaries. The rod did not contain a fixed number of feet; Saxton used 21 feet/rod (in 1603) as was also used in Sedbergh (Willan, 2005). Newby used about 11 to 16 feet/rod (in 1619) on the maps of Ingleborough described recently (Slater, 2004). The variation seems due to lack of standardization of the foot rather than the rod. The picture [not shown here for copyright reasons] shows how in 1536 Jacob Köbel suggested that a German surveyor should define the length of his rod by lining up the feet of ‘16 men, large and small’ as they came out of church on a Sunday! In 1688 an iron bar was set up in Paris to fix the toise, being 6 Paris feet, equivalent to 6.39 English feet. In 1844 a bronze standard yard was made (see but only in 1855 was the Imperial standard yard adopted by Act of Parliament.

The unit of the rod length was also used for areas, omitting the word ‘square’. Assuming that 5.5 yards is the agreed rod length, a (square) rod is then 30.25 square yards. Then 40 (square) rods denotes 1 rood (1210 square yards) and 4 roods equals 1 acre (4840 square yards, the Statutory acre). The word yard has to be used carefully since in Old English a yard was also 16 ft but varying locally according to the length of a foot, and in Middle English a yard (as in yardland) was one quarter of an acre, i.e. 1 rood. A picture from 1617 (Rawnsley, 1970) shows a surveyor with a short chain of some yards long, the title of which picture suggests that small squares of land were marked out in order to estimate land areas - as said to be the case by Linklater (2000).

Small distances were measured with solid rods, presumably of wood. The word pole is synonymous with rod, but what of the word ‘perch’? This is a Middle English word, derived from Latin pertica (a pole or measuring rod), and French perche. It is surmised that the length of 5.5 yards (16ft 6 inches) is as long as could be handled without excessive difficulty while remaining straight. A medieval lance or pike could be almost as long and the word lance is an obsolete length measure (OED). However, further enquiries show that medieval lances did not exceed about 14 feet and were not of a fixed length. It has also been suggested that the length of the rod derives from the observation that oxen pulling a plough could be controlled with a stick long enough to reach all the animals ( Folding rods are known.

The furlong (furrow long) seems rarely used in documents; it is now defined as 220 yards. The furlong in northern and north midlands districts was longer than the now Statute furlong. The furlong was equal to the Roman stadium, one eighth of a Roman mile so perhaps this is the best starting point, with strong agricultural and historical support, leading to definition of the rod length. Why is the rod a seemingly rather awkward number of feet or yards long? The factors of four and ten which people could handle easily in the 16th C and after perhaps provide the clue. In length terms four rods make a chain, ten chains make a furlong, 8 furlongs make a mile. In area terms four square rods make a daywork, 10 dayworks make a rood, 4 roods make an acre, 640 acres (10x4x4x4) make a square mile. The rod length needed to be large enough for measurement of plots of land of useful size but not too small to make errors become significant by repeated use of the rod. The ell, of 37.2 or 45 inches, is really too small for such distance measurement but its use in deeds is known in defining the length of the rod. In the deeds quoted above the word ell obviously is the same as a yard in length, there being 5.5 ells per pole. Once the absolute length of a yard is fixed and agreed everything else falls into place.

One could imagine that distances were measured by letting the rod ‘fall’, so explaining the synonym, but in practice the rod must have been laid more carefully on the ground, as described by Whitaker (2005), to resolve problems of uneven ground and measuring in a straight line. Early maps often give a linear scale in rods, perches or furlongs and there are a few illustrations which show long rods just lying around. The making of national maps using triangulation depends on measuring a long base-line accurately; the picture [not shown here for copyright reasons] illustrates the use of rods for this by Cassini in France in 1749 and is the earliest representation known to us of the systematic use of a set of rods to determine a length - maybe the decoration on maps required more interesting material than men using measuring poles. An early application of this method was the use of well-seasoned wooden rods by Jean Picard in 1669 to measure the 11.4 km base line from Paris to Fontainebleau for a triangulation to determine the precise size of a degree of latitude (Wilford, 2000). When a similar base line was set out by William Roy on Hounslow Heath in 1784, he used 3 glass tubes 20 feet long protected from damage in wooden boxes. He found that wooden rods (made of deal for its straight grain) varied in length too much because of the damp climate in Britain (see account by Owen and Pilbeam, 1992). The problems of lengths changing with humidity and temperature were certainly recognized by 1735 (Whitaker, 2005).

When frequent measurements of long distances became more important, as in the detailed mapmaking which commenced in the 1700s, the limitations of using simple wooden poles were largely overcome by using steel chains, such as that made by Jesse Ramsden for the Ordnance Survey in about 1780. From its invention by Edmund Gunter in 1620, the standard surveyor’s chain was 22 yards long but engineers commonly used a chain 100 feet long. The earliest use of a chain to measure a very long distance, probably the longest ever measured in this way, was by Richard Norwood in 1633 to 1635. He stretched his chain repeatedly all the way along the road from London to York. Allowing for the twists in the road he calculated the cities to be separated by 179 miles, and by measuring the height of the sun in both places found the length of a degree of latitude to be 69.2 miles, amazingly close to the correct value (Wilford, 2000).

Nearly three hundred years have elapsed since the first use of chains before the introduction of laser devices for measuring relatively short distances with ease and accuracy!


Caption for Picture [not shown on the web for copyright reasons] ‘16 men, large and small’
From “Geometrei: von künstlichen Messen” by Jacob Köbel, Frankfurt 1536 (with permission of the Herzog August Bibliothek Wolfenbüttel: Nx 62 (8))

Caption for Picture [not shown on the web for copyright reasons] Use of rods for base-line measurement
From “Discours du Méridien” by Jacques Cassini in 1749, Jean-Loup Charmet, Paris (as shown in “The Mapmaker’s Art”, John Goss, Studio Editions 1993.) Copyright ownership has unfortunately not been traced and apologies are made for any infringement of rights.