Talk:Cubit

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Intro[edit]

The intro needs to be rewritten. For the moment it states that - in cm - 6 palms is larger than 7 palms. The inches and feet are most likely off too.

in its current form, the introductory mention of the Egyptian cubit states that it is longer than a normal forearm. The following statement about the "natural cubit" is hopelessly garbled, please see my comment below at "Hmnh?" where I suggest a tentative rephrasing. Foxpoet (talk) 02:56, 1 March 2011 (UTC)

Metric Cubit?[edit]

Any pointers to a reference to this? I've NEVER heard of this unit of measurement.

18/03/06 Egypitan royal and sumerian Nippur cubit.

1. I have appended information to the nippur cubit paragraph concering Petries observations. --Michael saunders 22:47, 18 March 2006 (UTC)

2. reverted to old page after reading the rest of the material --Michael saunders 22:55, 18 March 2006 (UTC)

15/3/06 request for clarification your Gudea foot should be half a cubit or 15 fingers of 498mm. See here for more information user:michael saunders and here for further clarification discusses various reports on the Gudea rule

Nippur Elle a fantasy.

9/1/06

Paul Martin wrote:

"However, surely other standards in other not conserved materials (wooden for example) must have existed long times before, because with the temple C in Uruk-Warka, periode Uruk IV, constructed in about 3500 BC the Nippur cubit measure was already used. At the moment, for this, I dispose only of secundary sources, but I will try to find out the first researches affirming it."

Well, lets wait till the evidence is forthcoming. It would have to be high quality as well, just measuring a single square building that looks as tho it might be built in those units is nowhere near enough. Speculation is what made such a mess of this subject in the first place. There is no way this thing is a standard. Its divisions are irregular, there are 2, then 3, then 10 etc...Its fantasy AFAIC. Rottlander is still working from pre-war diffusionist ideas. The use of fixed ratios is also fantasy. Steccini was the great supporter of this, and his ideas are now seen to be baseless. You need to understand the political context in which this bar was published.

7/1/06

Changes made again.

2750 is earlier than the so called Nippur cubit. 'used for millenia before this' (deleted) must be supported by at least some evidence. Where is the evidence?

4/1/06

Some changes made because the identification of the Nippur 'cubit' as a rule, let alone a standard, is highly questionable. The divisions are highly irregular, and the conclusions of the 19th and early 20th C metrologists concerning Mesopotamia are now known to have been seriously compromised by ideology. Any suggestion of connections between standards is also highly questionable, and the diagram should really also be deleted.

If this article is develop correctly, or as correctly as possible, all statements should be supported by a published reference, and directly related to surviving physical artefacts or an extant text.

Otherwise the erroneous conclusions of the early metrologists are simply being repeated for posterity.

D


Hi User:80.44...
I didn't see your talk-page contribuation before Jan. 8th. Then I didn't have the time to reply.
You wrote: "2750 is earlier than the so called Nippur cubit". About 2750 BC is the date of the Old Royal cubit "estabished from surviving architectural evidence". In opposition to the NE of about 2650 BC (~2800 BC according to Rottländer) is the first "graduated copper bar cubit". That's a difference! You also wrote: "the identification of the Nippur 'cubit' as a rule [...] is highly questionable." I never heard someone to contest it. Do you have sources they did? You wrote: The NE specimen "divisions are highly irregular." I'm not according. You must have in mind that's the very first graduated ruler man made, at least – of course – the first one which is preserved. So, if you take the incontested main measure of this stick, i.e. about 51.8 cm. So the Nippur digit of this specimen (not to confound with the general measure Nippur Ell. Even if in it's time and at Uruk where it was found it was surely a kind of standard, or you think someone made a more than 45 kg weighting graduated copper bar "just for fun"?) measured 51.8/30 = 1.72,6, cm.
As like you can see here the length over all was 110.35 cm: 110.35/1.72,6, = 63.91 digits instead of 64 digits, 99.86 %. Not so bad for a more than 4.5 millenia old first length standard in humankind history! The other carried measures are respectively, always in digits: 14.83 instead of 15.00, then (the worst small measure) 3.88 vs. 4.00, then 12.13 vs. 12.00, then 13.99 vs. 14.00, then 3.91 vs. 4.00, then 3.07 vs. 3.00, then at last 12.10 vs. 12.00. Admittedly, if you compare this to our laser guided modern production, it's horribly imprecise. And even in Greek and Roman ancient times, they worked much more accurately. But we must have respect as regards to these pioneers in metrology. However, surely other standards in other not conserved materials (wooden for example) must have existed long times before, because with the temple C in Uruk-Warka, periode Uruk IV, constructed in about 3500 BC the Nippur cubit measure was already used. At the moment, for this, I dispose only of secundary sources, but I will try to find out the first researches affirming it.
Without doubt both the Nippur cubit and the Salamis cubit 28/30 NE were used long times before the Old Royal cubit. From this one, as I know, outside the "architectural evidence", we havn't any graduated rule. The very beautiful and very good worked Egyptian rules in the museums are all posterior, thus they used the (New) Royal cubit and not the ORC.
You also wrote: "The conclusions of the 19th and early 20th C metrologists concerning Mesopotamia are now known to have been seriously compromised by ideology." Surely, in the most cases your statement is applicable. Even for the newer Rottländer works in several aspects and concerning about five or six points I have serious objections against his conclusions or affirmations. However, excepting these criticable, critic worthy points, the rest of this works is now seen, not only by me, but also by the most other colleagues as the actual standard theorie. (The doubtful points are meanly: the so-called megalithic yard, the sumerian pendular measure and meso-american phantasy-diffusionism.) But for the rest, it seems clear that the ancient measures in the Fertile Crescent and in Mediterranean Basin are related by now identified, clearly established, plain ratios.
At last, you have to take into consideration, that in ancient times integer ratios – decimal fractions didn't exist, because the positional decimal system was not yet invented – were the only way to compare different measures. Therefore, attestable, also the ancient metrologists like Heron and others, always reasoned in "ratio relationships".
So long, Paul Martin 17:22, 16 January 2006 (UTC)

Older discussions[edit]

Length of the Old Royal cubit[edit]

20.6 inches equals one cubit.

Isn't this what the article states? Ian Cairns 01:48, 29 Dec 2004 (UTC)
Rktect 8/13/05
No, not at all.
Some really basic objections:
1.) There are many different cubits
2.) used by many different cultures
3.) in many different periods.
4.) Some are defined according to a strict standard of measure
5.) some are defined by body measure
6.) some are defined as divisions of the side of a field
7.) The base measure varies so that there are cubit systems
8.) based on fingers, digits, dj and sheshi
9.) based on uban and rule of thumb
10.) based on palms, hands, fists, spans and quarters
11.) based on feet, remen, ordinary cubits, great cubits and ni bw or ells
12.) A Mesopotamiand cubit would be divided into hands.
13.) Three hands would be a foot and four hands an ordinary cubit
14.) Depending on where and when you are talking the finger unit
could be a little finger of 15 mm, a ring finger of 16.67 mm,
an index finger of 17.67 mm a first finger of 20 mm or a thumb of 25 mm.
15.) A hand could thus be anywhere from 60 mm to 100 mm
16.) An foot could thus be anywhere from 180 mm to 300 mm
17.) An ordinary remen would be a foot plus a hand or 4 hands = 400 mm
18.) An ordinary remen would be a foot plus 2 hands or 5 hands = 500 mm
19.) A Great Cubit would be a foot plus 3 hands or 6 hands = 600 mm = 2 ft.


20.) An Egyptian cubit would be divided into palms.
21.) Four palms would be a foot and five palms an ordinary cubit
22.) The finger unit or dj is always 18.75 mm
23.) every one finger increase has its own unit name.
24.) A palm four fingers or dj = 75 mm
25.) An foot is 4 palms = 300 mm
26.) A remen is a foot plus a palm or 5 palms = 375 mm
27.) An ordinary cubit is a foot plus 2 palm or 6 palms = 450 mm
28.) A Great Cubit would be a foot plus 3 palms or 7 hands = 525 mm
29.) A Ni bw or elle is literally 2 feet or 600 mm
30 To those you can add the cubits of the Greeks, Romans and English
31 The English cubit is retained as the diamond mark on a Stanley tape measure

That last item is interesting as it documents a system of board measure and cloth measure that link to a foot of 12.8 ynches and a remen of 15" and a yard of 38.4" as well as the cubit of 19.2". Rktect 13:53, 7 October 2005 (UTC)

The Stanley "cubit"[edit]

Comment to the above: Carpenters seem to believe that the diamonds on the Stanley tape measures were put there as aids for finding the right truss spacing using plywood sheets [1] [2] [3]. But now rktect tells us that Stanley put them there as proof of existence of the English cubit! Will this never end? -- Egil 16:18, 7 October 2005 (UTC)


"longtime puzzle by mark996 on 04/22/05 at 18:22:44 I hate to admit that I've been a carpenter for 30 years or more and I've never found out those mystery marks on most all tape-measures. It seems that there's an arrow every 19 3/16 + inches. Can anyone please make me look foolish and solve this riddle. Thank you Mark996 "

clearly Mark996, a carpenter with 30 years experience, doesn't know what the mark is doing there

"Re: longtime puzzle by Robert Fogt on 04/23/05 at 02:45:15 This is used when laying out engineered floor trusses that are 3-1/2" thick, there are six trusses or five spaces per 8' piece of subfloor. The red diamond at 16" is for wall studs, the black diamond at 19 3/16 is for trusses. I know Stanley uses diamonds, while other brands may use arrows or just different colored marks."

Robert is taking a guess. In fact the ratio can be used to save on materials in walls floors or roofs.

I didn't say that Stanley put them there as proof of the cubit but rather that they are a vestigal remainder of an earlier system.

There are four marks on a Stanley tapemeasure commonly used for framing, 1', arrows at 16" diamonds at 19.2" and 2' marks. In modern modular systems most carpenters will use the arrows at 16" about 90 % of the time, (studs 16" OC) but all four marks have framing applications and allow a series of 4' x 8' sheets of plywood to repeatedly land on a stud, joist or rafter. Plywood is always laid so that its long dimension is perpendicular to the framing so while a sheet of plywood will span 8 bays and 9 framing members at 1'-0" OC, it will span 6 bays and 7 joists at 16" OC and 5 bays and 6 joists at 19.2" and 4 bays and 5 joists at 2'-0" OC. Plywood is designed so that if a sheet 1/2" thick will take the load for 16" OC, generally 5/8 or 3/4 will take the load for 19.2" OC. Thus there is a trade off that at a slight extra expense for the plywood, and some labor involved in cutting insulation, 1 stud, joist or rafter may be eliminated.

Just in case you wondered Egil, the diamond mark has been on Stanley tape measures since before Engineered trusses existed and if you think its there just for engineered trusses ask yourself why it isn't found on other tape measures such as Lufkin that framing carpenters use. Rktect 20:14, 7 October 2005 (UTC)

The Egyptian remen was borrowed by the Romans. Whether divided into palms or hands the cubit allows a 3/4/5 triangle to be constructed. In hands its a foot/remen/cubit. In palms its a quarter/foot/remen. What Paul refers to as the Roman construction remen is one of the oldest and most useful mathematical relationships known. Its still used by carpenters today to square corners. Federal Street 01:17, 22 October 2005 (UTC)

Wrong on both points. Gillings show that the relationship between both Egyptian units and the Roman unit is inexact, such as might be expected from three units all representing the human forearm. Egyptian use of the 3/4/5 triangle is conjecture. Septentrionalis 23:47, 23 October 2005 (UTC)

Cubit relations to the remen[edit]

Paul, to educate those who refuse to read references can we put together a list of credible online references to remen and cubits that we both agree on. I can find them easily in print, but a lot of what I find online is either dumbed down or speculative. My preference would be primary sources like Herodotus, [Vitruvious],[proportions], Ptolemy or well credentialed, well known discussions such as Gardiner, Gillings, IE Edwards. Who do you like? Federal Street 23:28, 23 October 2005 (UTC)

I don't find this--
Old Egyptian geometers could calculate the square root of two from the value of the hypotenuse of a Cubit. This well-attested old Egyptian unit was known as the "construction remen" and used a good approximation: 2×20/28 ≥ root 2.
--especially comprehensible. What does "the hypotenuse of a cubit" mean? A cubit is a linear measure, not a triangle. Are we trying to say that the Egyptians discovered that a right triangle with a hypotenuse of 28 units had legs of (approximately but not exactly) 20 units? If so, that discovery hardly constitutes "calculating" the square root of two. And what's with the greater-than-or-equal-to sign? 40/28 is definitely greater than the square root of two, not greater-or-equal. 65.213.77.129 (talk) 15:20, 16 September 2009 (UTC)



16-palms-cubit = 1.2 cm ?[edit]

"cubits of 8 palms, ~60 cm or 24 inches, like cubits of 9 palms, ~67.5 cm or 27 inches. From the late Antiquity a Roman 16-palms-cubit (ulna ~1.20 cm) is as well attested"

Is this supposed to be 1.2 meters? Kernow 15:55, 30 March 2006 (UTC)

The Bible Cubit?[edit]

When the Bible makes references to distances in cubits (particularly in Revelation), which version of the cubit is it referring? --Malebolge LX 17:06, 2 April 2007 (UTC)

Nobody knows. Presumably it's the fingertip-to-elbow cubit, but it might be a wrist-to-elbow cubit, or even a fingertip-to-opposite-elbow cubit. --Carnildo 19:54, 2 April 2007 (UTC)

The construction of the Bronze Sea (1 Kings 7:23-26) provides a window into the measure of a cubit, since the volume is 2000 baths. The walls were sloped, since it was shaped like a lily, so a frustum of a cone suffices for an approximation, since an approximation for a bath of about 22 liters was used.

A cubit works out to be about 19.27" [4] This is an elbow to fingertip measurement. Mine is about 19.265" (19¼+1/64") --No938 (talk) 03:37, 21 July 2008 (UTC)


hunh?[edit]

The sentence beginning "The distance between thumb and another finger to the elbow on an average person and measures about 24 digits..." doesn't scan. What is meant by this? Herostratus (talk) 05:36, 30 December 2007 (UTC)

Maybe whoever wrote it meant the cubit is measured as the distance between the thumb (or any finger) to the elbow of an average person. But maybe not. Good question, Herostratus. —Preceding unsigned comment added by JGC1010 (talkcontribs) 01:25, 20 January 2008 (UTC)

I had the same question, especially since I have very average modern proportions and I couldn't find any approximation that fit. My best guess is that it is a garbled reference to the palm unit. I am a wiki neophyte, but my suggested revision is:

"In an average person, the distance across the hand between the index and little finger is related to the the length of the forearm at a ratio of about 6:1, or 24 digits. This anthropomorphic measure, typically about 18 inches (46 cm), is sometimes referred to as a "natural cubit," used in classical times as a practical method of measurement."
FAR be it from me to mess with this page, it's an emotional issue. Anyone braver than me that wishes to post my interpretation of the garbled text is welcome to. Foxpoet (talk) 02:45, 1 March 2011 (UTC)


The Ark.[edit]

I've removed:

"The ark was measured as 300 cubits long, 50 cubits wide and 30 cubits high. Using an 18-inch cubit, as noted at the start of the article, this would make the ark about 450 feet long, 75 feet wide and 45 feet high, these shipbuilding dimensions were reached in the 19th Century (when the Great Eastern was built)."

Primarily because it was just tacked on to the bottom of a section and really needed to be put somewhere else. However, I have a few problems with it.

  • "Using an 18-inch cubit" is OR. I'd like to see a reference to an expert speculating on the lenght rather than a guess (X says the most likely lenght of a cubit used in Genesis was ... making the ark...). If we can't find a reference I'd prefer to see "The ark was measured as 300 cubits long, 50 cubits wide and 30 cubits high, however which lenght of cubit was used it unknown."
  • And the whole shipbuilding sentence seems contextually unsound. Maybe "these shipbuilding dimensions were not reached until the 19th Century (when the Great Eastern was built)." if that's what it's trying to say.

Duggy 1138 (talk) 05:00, 14 July 2008 (UTC)


Biblical Cubit[edit]

The measure, cubit, can be found looking at the volume of the Bronze Sea (1Kings 7:23-26).

The number of cubits3 can be determined from the wall taper and the volume of baths given.

Taken beyond significant digits, I find 19.269516 inches to be a cubit, which is elbow to tip of middle finger.

Check the calculations and references here. [5] --No938 (talk) 14:05, 24 May 2009 (UTC)

Hi, the link you gave is no longer valid, and the site is no longer there. Can you give another link? Thanks! Misty MH (talk) 15:40, 29 July 2013 (UTC)


Thai cubit[edit]

  • The Thai sok (ศอก elbow) is 24 nieu (Thai: นิ้ว digit). Upon metrification, they defined the sok as exactly 0.5 metres (1.043 Roman cubits.)
    • I have no idea as to its antiquity, but the usage can be verified at Wa (unit). --Pawyilee (talk) 20:27, 8 December 2009 (UTC)

Quantum Cubit[edit]

(This is by the user Cartref) The quantum cubit is a unit of a quantum brain. To understand this, let's go to binary. Binary is a system of 1s and 0s. In computers, binary switches are used as 'gateways' to put different bits of information on different tracks of the computer. The 'gateways' are called bits. BUT, with a quantum computer, because quantum means 'in two places at once', a quantum bit (called a cubit) can be 1 and 0 at the same time! This means, if the bits travel in clumps, to process fast (in a normal computer, this would clog up the system), then in a literal instant, they would be sorted! So, a computer of 32 quantum cubits would be much, much faster than a normal computer the size of a large garden pond!

Cartref: Please refer to the term Qubit, with a "Q." It is a portmanteau of "quantum" and "bit," completely unrelated linguistically to the old unit of measure. Foxpoet (talk) 02:45, 1 March 2011 (UTC)

Royal Cubit = 7 palms x 4 fingers (4 digits) = 28 parts[edit]

"The royal cubit was 523 to 525 mm (20.6 to 20.64 inches) in length[1], and was subdivided into 7 palms of 4 digits (4 fingers) each, for a 28-part measure in total."

I added the explanation that the palm is divided into 4 fingers or 4 digits of equal length. - p. 31 Sacred Geometry by Stephen Skinner (Sterling Publishing, 2006) - Brad Watson, Miami, FL 64.136.26.22 (talk) 16:53, 30 October 2010 (UTC)

Unreferenced material[edit]

This article seems to have a lot of unreferenced material. It's been tagged since April as needing inline citations. Unless anyone objects, I plan to start removing unreferenced stuff in the next couple of days, adding it here for reference and discussion. Then, once each bit is properly sourced, it can go back into the article. Does that make sense? Oh, will anyone mind if I switch the references to list-defined at the same time? Justlettersandnumbers (talk) 01:03, 20 September 2011 (UTC)

So, I have gone ahead and done that. The totally unreferenced material that I have removed is behind the pleasantly coloured green bar. I suggest that as bits are sourced and added back into the article, they are struck through here so that it's obvious what is left. I couldn't think of a better way of doing this. Leaving it in the article was not an option IMO. I mean, just to take one example, "the Mesopotamian cubit measured ... 65 Roman cubit". But how did those clever Mesopotamians know what the length of the Roman cubit would be a couple of thousand years after they were dead?
Justlettersandnumbers (talk) 01:08, 21 September 2011 (UTC)
Wow that was a lot of information removed. I'd love to see references for some of it. Since it appears to be similar in formatting, I am guessing the same person added a lot of that. Can you contact the person, and show them this, so that they can add a reference for where they got all that information? It seems like it wasn't just "made up", and it's quite specific. Maybe they just forgot, or didn't know how to add a reference. I know that I've struggled with the latter, time and again, and citations differ from article to article, and even within a single article. Contact them, please? Thanks. Misty MH (talk) 15:59, 29 July 2013 (UTC) Misty MH (talk) 15:59, 29 July 2013 (UTC)
I'd love to see a source/citation for this: "From late Antiquity, the Roman ulna, a four-foot cubit (about 120 cm) is also attested. This length is the measure from a man's hip to the fingers of the outstretched opposite arm." A 4' cubit would make an impressive ship/barge indeed, larger than any known ship since! (4-foot cubit!) Misty MH (talk) 11:35, 25 January 2014 (UTC)

The 'cubit' is a traditional unit of measurement of length, based on the length of the forearm: from the elbow to the tip of the middle finger.[edit]

I gave further explanation to the opening sentence... The cubit is a traditional unit of length, based on the length of the forearm: from the elbow to the tip of the middle finger. - Brad Watson, Miami (talk) 18:48, 29 September 2012 (UTC)

Standard/Biblical cubit: 6 palms x 4 fingers = 24 units, Egyptian Royal cubit: 7 palms x 4 fingers = 28 units[edit]

I tweaked the following with an excellent reference...

The cubit is a traditional unit of length, based on the length of the forearm: from the elbow to the tip of the middle finger. Cubits of various lengths were employed in many parts of the world in Antiquity, in the Middle Ages and into Early Modern Times.

The Egyptian hieroglyph for the cubit shows the symbol of a forearm. According to the Ancient Egyptian units of measurement, the Egyptian Royal cubit was subdivided into 7 palms of 4 fingers/digits each; surviving cubit rods are between 52.3 and 52.9 cm (20.6 to 20.8 inches) in length.[3]

Over time, various cubits and variations on the cubit have measured:

  • Standard/Biblical cubits: 6 palms x 4 fingers = 24 digits
  • Egyptian Royal cubits: 7 palms x 4 fingers = 28 digits[3]<ref]Sacred Geometry p. 31 by Stephen Skinner (Sterling, 2006)</ref] - Brad Watson, Miami (talk) 19:16, 29 September 2012 (UTC)


I see several problems here. First Merriam-Webster is not a reliable reference for complex archaeological questions. For giving us a general definition of the cubit as based on the length of the forearm, yes. For defining it specifically as extending from the elbow to the tip of the middle finger, no. In fact ancient cubits were more often defined as ending at the wrist or at the knuckle of the middle finger (without specifying which knuckle, although presumably the more prominent one).
There was no single Biblical cubit; there were at least two, and possibly several others depending on interpretation. It is also not clear when those Biblical cubits might have been used, since various parts of the Jewish and Christian bibles were composed at different times, then underwent considerable modification before being put into writing, more modifications still before reaching the state of the earliest surviving manuscripts.
There was no single standard cubit in ancient times, and if there was what reason is there to think that it would have been the same one used by the comparatively small Jewish and Christian minorities?
We do not use other Wikipedia articles as references or mention them in the text, since they are unreliable tertiary sources and could be renamed or disappear at any time. We can Wikilink to them or put them in See also.
The book you cite Sacred Geometry by Stephen Skinner is full of New Age mystical stuff. It is not a serious source. Zyxwv99 (talk) 22:46, 29 September 2012 (UTC)
    • ^ Arnold 1991: 296
    • ^ Cf. Biblical Archaeology Review, March–April 1983, and Newsletter and Proceedings of the Society for Early Historic Archaeology, issue 159.
    • ^ Cite error: The named reference arnold was invoked but never defined (see the help page).