Palm (unit)

The palm is an obsolete anthropic unit of length, originally based on the width of the human palm and then variously standardized. The same name is also used for a second, rather larger unit based on the length of the human hand.

The width of the palm was a traditional unit in Ancient Egypt, Israel, Greece, and Rome and in medieval England, where it was also known as the hand,. handbreadth, or handsbreadth.. The only commonly discussed "palm" in modern English is the biblical palm of ancient Israel.

The length of the hand—originally the Roman "greater palm"—formed the palm of medieval Italy and France.

In Spanish customary units ' or ' was the palm, while ' was the span, the distance between an outstretched thumb and little finger.

In Portuguese ' or ' was the span.

History

Ancient Egypt

The Ancient Egyptian palm ( egy, shesep) has been reconstructed as about . The unit is attested as early as the reign of Djer, third pharaoh of the First Dynasty, and appears on many surviving cubit-rods.

The palm was subdivided into four digits () of about .

Three palms made up the span () or lesser span () of about . Four palms made up the foot () of about . Five made up the of about . Six made up the "Greek cubit" () of about . Seven made up the " royal cubit" () of about . Eight made up the pole () of about .

Ancient Israel

The palm was not a major unit in ancient Mesopotamia but appeared in ancient Israel as the , , or ( he, טפח, ."a spread"). Scholars were long uncertain as to whether this was reckoned using the Egyptian or Babylonian cubit,. but now believe it to have approximated the Egyptian "Greek cubit", giving a value for the palm of about ..

As in Egypt, the palm was divided into four digits ( or ) of about and three palms made up a span () of about . Six made up the Hebrew cubit ( or ) of about , although the cubits mentioned in Ezekiel follow the royal cubit in consisting of seven palms comprising about .

Ancient Greece

The Ancient Greek palm ( grc-gre, παλαιστή, ''palaistḗ'', , ''dō̂ron'', or , ''daktylodókhmē'') made up ¼ of the Greek foot (''poûs''), which varied by region between .. This gives values for the palm between , with the Attic palm around ..

These various palms were divided into four digits (''dáktylos'') or two "middle phalanges" (''kóndylos''). Two palms made a half-foot (''hēmipódion'' or ''dikhás''); three, a span (''spithamḗ''); four, a foot (''poûs''); five, a short cubit (''pygōn'');. and six, a cubit (''pē̂khys'').

The Greeks also had a less common "greater palm" of five digits.

Ancient Rome

The Roman palm ( la, palmus) or lesser palm (') made up ¼ of the Roman foot ('), which varied in practice between but is thought to have been officially . This would have given the palm a notional value of within a range of a few millimeters.

The palm was divided into four digits (') of about or three inches (') of about . Three made a span (' or "greater palm") of about ; four, a Roman foot; five, a hand-and-a-foot (') of about ; six, a cubit (') of about .

Continental Europe

The palms of medieval ( la, palma). and early modern Europe—the Italian, Spanish, and Portuguese ' and French '—were based upon the Roman "greater palm", reckoned as a hand's span or length.

In Italy, the palm ( it, palmo) varied regionally. The Genovese palm was about ; in the Papal States, the Roman palm about according to Hutton but divided into the Roman "architect's palm" (') of about and "merchant's palm" (') of about according to Greaves; and the Neapolitan palm reported as by Riccioli but by Hutton's other sources. On Sicily and Malta, it was .

In France, the palm (french: palme or ') was about in Pernes-les-Fontaines, Vaucluse.

Palaiseau gave metric equivalents for the ''palme'' or ''palmo'' in 1816, and Rose provided English equivalents in 1900:

England

The English palm, handbreadth, or handsbreadth is three inches (7.62 cm) or, equivalently, four digits. The measurement was, however, not always well distinguished from the hand or handful, which became equal to four inches by a 1541 statute of Henry VIII. The palm was excluded from the British Weights and Measures Act of 1824 that established the imperial system and is not a standard US customary unit.

Elsewhere

The Moroccan palm is given by Hutton as about .

Notes

References

{{DEFAULTSORT:Palm, Unit
Units of length
Human-based units of measurement
Obsolete units of measurement