1. The Yard, the Foot, the Inch

The term Yard, the Old English ‘gerde’ or ‘yerde,’ a wand or rod, became specially applied to a wand of 3 feet, or 4 spans; from this double mode of division and from its convenient length the cloth-yard of 3 feet became generally used. It has the convenience of being a half-fathom, and of being divisible not only into feet and inches, but also sexdecimally into units which are familiar as limb-lengths of the cubit and span system.

The half-yard corresponds to the Cubit.

The quarter-yard is a Span.^[12]

The eighth is a Finger; women constantly measure linen approximately by the length of the bent middle finger.

The sixteenth is a Nail; this is the length of the half-finger, the last two joints of the middle finger.^[13]

While the yard is lawfully divided into halves, quarters, eighths, and nails, it may also, as a measure of 3 feet, be divided into 36 inches. Yard-measures are usually divided in both ways, on one side into 16 nails, on the other into inches.

It is customary to say either a yard and a quarter, or 45 inches, or 3 feet 9 inches. Or to say either 58 inches or 4 feet 10 inches; but it is not customary to say a yard and 22 inches. We cease to use the yard as unit when we cannot express its fractions sexdecimally.

The Foot is lawfully divided into 12 inches; but there is nothing to prevent it being divided decimally, or otherwise, as convenient.

The Inch is divided according to convenience, either

Sexdecimally, into halves, quarters, &c., down to sixty-fourths. This is the usual division.

Duodecimally, into 12 lines.

Decimally, into tenths and hundredths.

Steel foot-rules usually show all three of these scales.

Some trades may have special scales. Thus type-founders divide the Inch into 6 ‘picas’ each = 2 lines, and the ‘pica’ into 12 points each = 1/6 line or 1/72 inch. Nonpareil type is 6 points; Brevier is 8 points.

2. Standards of the Linear Measures

Tables of measures, from the earliest, about 1500, down to quite recent times, usually began by stating that ‘Three barley-corns make an inch’ or that ‘Geographical measures begin at a barley-corn and increase upward to a league,’ &c.

King David I of Scotland (c. 1150) is credited with the pronouncement that the Scots inch was to be the mean measure of ‘the thowmys of iij men, that is to say an mekill man and a man of messurabil statur and of a lytell man. The thoums are to be messurit at the rut of the nayll.’ But no more in Scotland than in England, or elsewhere, has the inch ever been anything but a division of the foot.

A standard of the English foot was fixed in Old St. Paul’s Church, London, and was known as Paul’s foot, all measures being referred to the standard ‘qui insculpitur super basim columpnÆ in ecclesia Sancti Pauli.’ In 1273 a deed gave the measurement of land ‘according to the iron ell [yard] of the King’s palace.’

The present standard yard is a bronze bar kept in London, the length of which agrees exactly with the yard, still extant, of Tudor times. A set of standard measures of length is fixed along the base of the northern wall of Trafalgar Square,^[14] and another set is in the flooring of the Guildhall. Sets are also fixed to public buildings in several chief towns of the United Kingdom.

As metal rods vary in length according to temperature, comparisons with a standard measure should be made at the normal temperature of 62°. But there is an alloy of steel and nickel (42 per cent.), named Invar, which is not perceptibly affected by temperature.

A pendulum beating seconds at sea-level and at normal temperature measures 39·1393 inches at Greenwich (Act of Parliament, 1824). This length varies in different places from the variations of gravity due to the ellipticity of the earth and local causes of deviation.

3. The Hand

The popular ‘hand’ was the ‘palm’ of ancient times, four digits or finger-breadths.

Pes habet palmos iv, palmus habet digitos iv (Frontinus).

‘Foure graines of barlye make a finger; foure fingers a hande; foure handes a foote’ (Eden, 1566).

But the present Hand for horse-measurement is ‘the measure called a Handful used in measuring the height of horses, by 27 Hen. 8, Chap. 6, ordained to be 4 inches’ (Sam. Leake, 1701). This is part of an old popular duodecimal division of the foot into 3 hands of 4 inches, then of the inch into 3 barleycorns (lengthwise) each of 4 poppy-seeds, and of these again into 12 hairbreadths.

In Austria this horse-measure is the Faust or fist.

Another very widely spread limb-measure is that of the fist with the thumb projecting, roughly = 6 inches. It is the Shaftment of some parts of England, scÆft-mund (shaft-hand) in Old English, bawd in Wales; the somesso of Italy, the kubdeh of Egypt, the taim of Burma.

In the Laws of Æthelstan (1000) a measurement is given as 9 feet, 9 shaftments, and 9 barleycorns, i.e. 9 feet + 9 half-feet + 3 inches.

4. The Ell

The yard, being 4 spans, was formerly one of the Ells, measures of 3, 4, 5 or more spans, related to the cubit of 2 spans. The Scots yard, of 37 inches, was always known as an Ell, and it was only gradually that our yard took the place, for cloth measure, of the Ell of 5 spans = 45 inches, which was long maintained by statute. The yard and the ell were usually distinguished as virga and ulna in statutes, but sometimes ulna meant a yard.

Both yard and ell were divided into halves, quarters, and nails (sixteenths).

See Chap. XVI (The Ells), and Chap. XX (section on the Nail and the Clove).

5. The Rod, Furlong, Mile, and League

The earliest table of English linear measures is probably that in Arnold’s ‘Customs of London,’ c. 1500.

Thus, in 1500, the furlong was 125 × 5 = 625 feet, and the mile = 5000 feet = 1666·6 yards.

The mile was originally the Roman mile, 1000 paces or 5000 Roman feet, and = (5000 × 11·67)/(3 × 12) in. = 1621-1/3 yards. So in course of time our mile had become 5000 English feet.

But the linear unit for land measurement was not, as in the Roman system, a pertica or rod of 10 or 12 feet; it became very early, on the Teutonic system, a rod of 16 feet, with varieties, under French influence later on, of 18, of 21 and 24 feet.

In early Plantagenet times, not later than Edward I, the statute rod was fixed at 5-1/2 yards or 16-1/2 feet. Thus, while the rood, that is the field-furlong, was 40 rods or perches of 16-1/2 feet = 660 feet, the itinerary furlong, 1/8 mile, remained 625 feet, ‘xxxviij perchis sauf ij fote’ (Arnold’s ‘Chronicle’). This clashing of the new statute rod, and its multiple the rood or field-furlong of 40 rods, with the ancient itinerary furlong now only = 37·87 rods, was rectified in Tudor times, probably temp. Henry VII, but definitely by a statute of Elizabeth which raised the furlong to coincide with the rood. The mile thus became of its present length, 8 furlongs of 40 rods of 5-1/2 yards = 1760 yards = 5280 feet. The mile has then successively been:

For long measurements chains came into use, and shortly after 1600 Edward Gunter introduced, for surveying purposes, measurement by a chain of 4 rods, i.e. a ‘brede’ or ‘acre-brede,’ the breadth of an acre of 40 × 4 rods, divided into 100 links.

So the multiples of the yard are now:

The Scots mile and the Irish mile were equally 8 furlongs of 40 rods, but Scots and Irish rods (see Chap. XIV).

The term Yard has been used for certain large land-measures. These, with the evolution of the Rod, will be given in the next chapter.

The League

It has been seen that the Persian Parasang was three meridian miles, or 3000 Olympic fathoms. France retains this as the lieue marine of 20 to the degree, and Southern France long retained a league of 3 miles each of 1000 toises or cannes. But in Roman times the Leuca or Leuga of Gaul was 1-1/2 Roman miles. It passed to medieval England at about the same length, being defined as duodecim quaranteinis, 12 furlongs or roods of 40 rods.