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.[1]

A diagram of various units derived from the human hand. The palm (3) was originally the width of the palm but was standardized as the somewhat smaller width of four digits (6). The related shaftment (1) and hand (2) were the width of the palm plus an open or closed thumb. The other units are the span (4) and finger (5).

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,[2][lower-alpha 1] handbreadth,[3] or handsbreadth.[3][lower-alpha 2] 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 and in Portuguese "palm" (palmo or palmo de craveira) was the span, the distance between an outstretched thumb and little finger.

History

Ancient Egypt

Palm (D48) in hieroglyphs

Detail of the cubit rod in the Museo Egizio of Turin, showing digit, palm, hand and fist lengths

The Ancient Egyptian palm (Ancient Egyptian: shesep) has been reconstructed as about 75 mm or 3 in.[lower-alpha 3] The unit is attested as early as the reign of Djer, third pharaoh of the First Dynasty,[5] and appears on many surviving cubit-rods.[6]

The palm was subdivided into four digits (djeba) of about 19 mm (0.75 in).

Three palms made up the span (pedj) or lesser span (pedj-sheser) of about 22.5 cm (9 in). Four palms made up the foot (djeser) of about 30 cm (1 ft). Five made up the remen of about 37.5 cm (1 ft 3 in). Six made up the "Greek cubit" (meh nedjes) of about 45 cm (1 ft 6 in). Seven made up the "royal cubit" (meh niswt) of about 52.5 cm (1 ft 9 in). Eight made up the pole (nbiw) of about 60 cm (2 ft).

Ancient Israel

The palm was not a major unit in ancient Mesopotamia but appeared in ancient Israel as the tefah,[7] tepah,[8] or topah[8] (Hebrew: טפח‎, lit. "a spread").[9] Scholars were long uncertain as to whether this was reckoned using the Egyptian or Babylonian cubit,[7] but now believe it to have approximated the Egyptian "Greek cubit", giving a value for the palm of about 74 mm or 2.9 in.[8]

As in Egypt, the palm was divided into four digits (etzba[7] or etsba) of about 18.5 mm (0.73 in) and three palms made up a span (zeret) of about 22.1 cm (9 in).[8] Six made up the Hebrew cubit (amah[7] or ammah) of about 44.3 cm (1 ft 5 in), although the cubits mentioned in Ezekiel[10] follow the royal cubit in consisting of seven palms comprising about 51.8 centimeters (1 ft 8 in).[8]

Ancient Greece

The Ancient Greek palm (Greek: παλαιστή, palaistḗ, δῶρον, dō̂ron, or δακτυλοδόχμη, daktylodókhmē)[11] made up ¼ of the Greek foot (poûs), which varied by region between 27–35 cm (11 in–1 ft 2 in).[12] This gives values for the palm between 6.7–8.8 cm (2.6–3.5 in), with the Attic palm around 7.4 cm (2.9 in).[13]

These various palms were divided into four digits (dáktylos) or two "middle phalanges" (kóndylos).[13] Two palms made a half-foot (hēmipódion or dikhás); three, a span (spithamḗ); four, a foot (poûs);[13] five, a short cubit (pygōn);[14] and six, a cubit (pē̂khys).[13]

The Greeks also had a less common "greater palm" of five digits.[15]

Ancient Rome

The Roman palm (Latin: palmus) or lesser palm (palmus minor) made up ¼ of the Roman foot (pes), which varied in practice between 29.2–29.7 cm (11.5–11.7 in)[16] but is thought to have been officially 29.6 cm (11.7 in).[14] This would have given the palm a notional value of 7.4 cm (2.9 in) within a range of a few millimeters.[17]

The palm was divided into four digits (digitus) of about 1.85 cm (0.7 in) or three inches (uncia) of about 2.47 cm (1.0 in). Three made a span (palmus maior or "greater palm") of about 22.2 cm (9 in);[lower-alpha 4] four, a Roman foot; five, a hand-and-a-foot (palmipes) of about 37 cm (1 ft 3 in); six, a cubit (cubitus) of about 44.4 cm (1 ft 5.5 in).[19]

Continental Europe

Sign giving the metric equivalents of the units in use in the 17th century in the covered market of Pernes-les-Fontaines in the Vaucluse

The palms of medieval (Latin: palma)[20] and early modern Europe—the Italian, Spanish, and Portuguese palmo and French palme—were based upon the Roman "greater palm", reckoned as a hand's span or length.

In Italy, the palm (Italian: palmo) varied regionally. The Genovese palm was about 24.76–24.85 cm (9.7–9.8 in);[15][11][lower-alpha 5] in the Papal States, the Roman palm about 21.05 cm (8.3 in) according to Hutton but divided into the Roman "architect's palm" (palmo di architetti) of about 22.32 cm (8.8 in) and "merchant's palm" (palmo del braccio di mercantia) of about 21.21 cm (8.4 in) according to Greaves;[11][lower-alpha 6] and the Neapolitan palm reported as 20.31 cm (8.0 in) by Riccioli but 21.80 cm (8.6 in) by Hutton's other sources.[15] On Sicily and Malta, it was 24.61 cm (9.7 in).[24]

In France, the palm (French: palme or pan) was about 24.61 cm (9.7 in) in Pernes-les-Fontaines, Vaucluse,[24] and about 24.76 cm (9.7 in) in Languedoc.[15]

Palaiseau gave metric equivalents for the palme or palmo in 1816,[24] and Rose provided English equivalents in 1900:

Length of a palm in European cities

City	Lignes	Metric equivalent	Inches [25]
Florence (for silk, Palaiseau p.146)	131.63	[297] mm
Florence (for wool, Palaiseau p.146)	128.38	289.6 mm
Genoa (cloth measure, Palaiseau p.148)	106.9	241.1 mm
Genoa (linear measure, Palaiseau p.91)	107.43	242.3 mm
Genoa (Rose)		247 mm	9.72
Livorno (for silk, Palaiseau p.157)	128.41	289.7 mm
Livorno (for wool, Palaiseau p.157)	130.08	293.4 mm
Malta (cloth measure, Palaiseau p.160)	114.49	258.3 mm
Malta (linear measure, Palaiseau p.98)	115.28	260.0 mm
Naples (Rose)		263.6 mm	10.38
Palermo (cloth measure, Palaiseau p.168)	107.16	241.7 mm	9.53
Portugal (Palaiseau p.109)	96.36	217.4 mm	8.64
Rome (cloth measure, Palaiseau p.173)	109.52	247.1 mm
Rome (linear measure, Palaiseau p.111)	99	[223] mm
Sardinia (Rose)		248 mm	9.78
Spain (Rose)		219 mm	8.64
Metric equivalents from Palaiseau here rounded to 0.1 mm

England

English units of length

The English palm, handbreadth, or handsbreadth is three inches[26][27][28][29] (7.62 cm)[lower-alpha 7] or, equivalently, four digits.[29] The measurement was, however, not always well distinguished from the hand or handful,[26] which became equal to four inches by a 1541 statute of Henry VIII.[27][lower-alpha 8] 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 18.20 cm (7.2 in).[15]

See also

• Anthropic units

Notes

1. Over time, the hand has developed into a separate unit now used especially for measuring the height of horses. This hand, including the width of the thumb, is reckoned as 4 inches or 102 millimeters.[2]
2. In present usage, a "handbreadth" or "handsbreadth" is no longer taken as a proper unit but as a simple vague reckoning based on the human hand.[3]
3. More specifically, the 14 cubit-rods described by Lepsius in 1865 show a range from 74.7–75.6 mm (2.94–2.98 in).[4]
4. Despite the equality of this unit with other systems' spans, the Encyclopédie glossed the "greater palm" as the length rather than the breadth of the hand.[18]
5. Unlike Greaves, who used the Guildhall standard foot, Hutton based his measurements on the fractured yard at the Exchequer,[21] about 1% of an inch shorter than the present yard.[22] Hutton's line is reckoned as the ​¹⁄₁₂th part of an inch.[23]
6. A sign in Vaucluse, France, claims the Roman palm was identical to its own 24.61 cm (9.7 in) standard.[24]
7. An exact figure since the adoption of the international yard and pound agreement during the 1950s and '60s by the nations using the English system.
8. Mortimer, e.g., notes that during his time "The hand among horse-dealers, &c. is four-fingers' breadth, being the fist clenched, whereby the height of a horse is measured",[27] showing a confusion of the notional separation of "palms", "hands", and "fists".

References

1. "palm, n.² 2", Oxford English Dictionary, Oxford: Oxford University Press.
2. "hand, n. 9", Oxford English Dictionary.
3. "handbreadth, n.", Oxford English Dictionary.
4. Lepsius, Karl Richard (1865), Die Altaegyptische Elle und Ihre Eintheilung, Berlin: Dümmler. (in German)
5. Clagett, Marshall (1999), Ancient Egyptian Science, Vol. III: Ancient Egyptian Mathematics, Philadelphia: American Philosophical Society, ISBN 978-0-87169-232-0.
6. Clagett, Marshall (1999). Ancient Egyptian Science, A Source Book. Volume 3: Ancient Egyptian Mathematics. Philadelphia: American Philosophical Society. ISBN 978-0-87169-232-0.
7. Hirsch, Emil G.; et al. (1906), "Weights and Measures", The Jewish Encyclopedia, Vol. XII, pp. 483 ff.
8. "Weights and Measures", Oxford Biblical Studies Online, Oxford: Oxford University Press, retrieved 15 January 2017.
9. "2947 tephach & 948 tophach", Strong's Numbers, Bible Hub, 2016.
10. Ezekiel 40:5, Ezekiel 43:13.
11. Greaves, John (1647), "The Romane Foot Compared with the Measures of Divers Nations", A Discourse of the Romane Foot and Denarius, from Whence, as from Two Principles, the Measures and Weights Used by the Ancients May Be Deduced, London: William Lee, p. 40.
12. Dilke, Oswald Ashton Wentworth (1987), Mathematics and Measurement, Reading the Past, No. 2, Berkeley: University of California Press, p. 26, ISBN 9780520060722.
13. Rossi, Cesare; Flavio Russo (2009), Ancient Engineers' Inventions: Precursors of the Present, History of Mechanism and Machine Science, No. 33, Cham: Springer, p. 14, ISBN 9783319444765.
14. Pryce, Frederick Norman; et al. (2012), "measures", The Oxford Classical Dictionary, 4th ed., Oxford: Oxford University Press, p. 917, ISBN 9780199545568.
15. Hutton, Charles (1795), "Palm", A Philosophical and Mathematical Dictionary, Vol. II, London: J. Johnson, p. 187.
16. Aylward, William (1999), "Linear Measure and Geometry in Roman Architectural Planning with Specific Reference to the Colonnaded Oecus at the Villa at Poggio Gramignano", A Roman Villa and a Late Roman Infant Cemetery: Excavation at Poggio Gramignano Lugnano in Teverina, Rome: L'Erma di Bretschneider, p. 190, ISBN 9788870629897.
17. Hosch, William L., ed. (2010), The Britannica Guide to Numbers and Measurement, New York: Britannica Educational Publications, p. 206, ISBN 978-1-61530-108-9.
18. Diderot, Denis; Jean Le Rond d'Alembert (eds.) (1765) Encyclopédie, ou dictionnaire raisonné des sciences, des arts et des métiers (in French) Neufchastel: chez Samuel Faulche Volume XI, N – PARI p.793
19. Smith, Sir William; Charles Anthon (1851) A new classical dictionary of Greek and Roman biography, mythology, and geography partly based upon the Dictionary of Greek and Roman biography and mythology New York: Harper & Bros. Table II, page 1025
20. Mantello, Frank Anthony Carl; et al., Medieval Latin: An Introduction and Bibliographical Guide, p. 443.
21. Hutton, Charles (1795), "Weight", A Mathematical and Philosophical Dictionary, Vol. II.
22. "yard", Sizes, Sta. Monica, 2004.
23. Hutton, Charles (1795), "Line", A Mathematical and Philosophical Dictionary, Vol. II.
24. Palaiseau, Jean-François-Gaspard (1816) Métrologie universelle, ancienne et moderne: ou rapport des poids et mesures des empires, royaumes, duchés et prinicipautés des quatre parties du monde, présenté en tableaux par ordre alphabétique de pays ou ville, et leur position géographique avec les anciens et nouveau poids et mesures du royaume de France, et l'inverse, avec la méthode pour opérer toutes les conversions par des nombres fixes, etc. ... (in French) Bordeaux: Lavigne jeune p.160
25. Rose, Joshua (1900). Pattern Makers Assistant (9th ed.). New York: D. van Nostrand Co. p. 264.
26. Phillips, Edward (1706). Kersey, John (ed.). The new world of words: or, Universal English dictionary. Containing an account of the original or proper sense, and various significations of all hard words derived from other languages. Together with a brief and plain explication of all terms relating to any of the arts and sciences; to which is added, the interpretation of proper names (The sixth edition, revised ... With the addition of near twenty thousand words ... ed.). J. Phillips. Retrieved July 2011. Check date values in: |accessdate= (help)
27. Mortimer, Thomas (1810). A general dictionary of commerce, trade, and manufactures: exhibiting their present state in every part of the world; and carefully comp. from the latest and best authorities. London: R. Phillips.
28. [n.a.] (1816). Encyclopædia Perthensis; or Universal Dictionary of the Arts, Sciences, Literature, etc., intended to supersede the use of other books of reference, Volume 16.
29. Le Clerc, George Louis, Comte de Buffon (1831). A natural history of the globe: of man, of beasts, birds, fishes, reptiles, insects and plants Volume 5. John Wright (trans.). Boston; Philadelphia: Gray and Bowen; Thomas Desilver, Jr.