Talk:Megalithic yard

Claim sourced to Ponting and Scott
I don't know why Paul Bedson isn't willing to agree that p.147 in the book Ruggles edited wasn't written by Alexander Thom and Archie Thom and not by anyone else, as if you look at the page before using Google books it's clear they wrote it. Dougweller (talk) 14:29, 22 April 2011 (UTC)

Sorry Doug, I got the wrong page number there. It's page 431 onwards. I've changed the citation accordingly. Paul Bedson ❉ talk ❉ 14:47, 22 April 2011 (UTC)

Angell
If we use Angell we need to point out that he has shown " that the statistics used by Thom to support his claims for the existence of the megalithic yard are invalid, and evidence for its existence extremely weak" which I am assuming is the source cited.

Then we have

Angell, Ian O. Megalithic mathematics, ancient almanacs or neolithic nonsense. Bull. Inst. Math. Appl. 14 (1978), no. 10, 253--258. (Reviewer: C. R. Fletcher.) SC: 01A10, MR: 80f:01002.

Discusses different explanations for the shapes of megalithic stone rings. The author briefly discusses some of the theories of Alexander Thom, which involve an astronomical calendar and an effort to make the circumference equal to 3 times the "diameter" rather than the irrational pi. He then discusses two new theories of his own. One explains the shapes of the stone rings as extensions of the ellipse, generated with three or four pegs and a string rather than with just the usual two. The other explains the shapes as an effort to store shadow lengths. Neither theory may be given entirely in earnest. A theme of the paper is how theories may start as intellectual games, go out of control, and be changed into pseudo-science

Archaeostatistics: Old Statistics in Ancient Contexts Author(s): N. R. J. Fieller Source: Journal of the Royal Statistical Society. Series D (The Statistician), Vol. 42, No. 3, Special Issue: Conference on Applied Statistics in Ireland, 1992 (1993), pp. 279-295

"It is a sad fact that the megalithic yard hypothesis itself is of negligible interest to archaeologists. From what is known of the development and structure of prehistoric societies over the areas and time spans involved in the construction of the circles, the hypothesis that a strict mensuration system, based on a common 'brass-edged whalebone yardstick', was in widespread use is not worth entertaining. It belongs to the semi-mystical fringe of archaeology concerned with ley lines, Atlantis and the like."

I'm not sure why Angell is used, but at the moment it is impossible to verify what is meant by " I. Angell (1979). The Megalithic yard." and it should probably be removed. Dougweller (talk) 20:59, 22 April 2011 (UTC) Dougweller (talk) 20:59, 22 April 2011 (UTC)

NPOV
I missed the removal from the lead of a clear statement that this is controversial. The lead must describe " any prominent controversies." Dougweller (talk) 04:52, 26 April 2011 (UTC)

John Neal
If John B. Neal has been considered an unreliable source due to some self-published whim, why is "All Done with mirrors" allowed an entire section on the Pseudoscientific Metrology page? Please revert or delete. In my opinion it should stay as one of the least "pseudoscientific" of the sources and best reviews of the subject. Paul Bedson ❉ talk ❉ 16:28, 27 April 2011 (UTC)

Science and Society in Prehistoric Britain
Also, I don't follow the logic of deleting "All done with mirrors" whilst allowing Richard Heath's review of it to stand as an external link. Please be careful when removing self-published sources that have been reliably reviewed in newspapers and the like. I'm quite happy to put the text back in without a quote but I think you'll find that losing the criticism of Thom's methodology using only one, non-megalithic measurement should balance the article even more in favour of his megalithic yard. Also, here's another Richard Heath article showing that the size comparisons came from Euan Mackie's "Science and Society in Prehistoric Britain". I'll see if I can get a copy but if anyone has one, page numbers would be great. Paul Bedson ❉ talk ❉ 16:45, 27 April 2011 (UTC)

My linked article on John Neal is defunct and link can be removed. I will find the data on Proposed Geometric Origins and publish it below (from Ivimy and Mackie). I agree that John Neal's analyses and theory about ancient metrology is a significant cultural work which belongs somewhere on Wikipedia, because it exists. If this was the 19th Century, think which ideas, now considered essential to science, would have been contested on Wikipedia - such as geological time, ice ages and evolution by selection. RichardDHeath

There was an extensive prehistoric linear measurement system in operation in Britain. For example The base unit was the Celtic foot of 332-333 milimetres. Long Man of Wilmington's head to toe height is 68.4 metres. Stone Street in Kent is ten megalithic miles length. From Stonehenge to the coastal Highcliffe Castle is 22 megalithic miles in a straight line with four proven ancient monuments along the way. The ancient measurement table is as follows: - One Celtic foot	       = 	332 – 333 mm, Celtic fōt 2½ Celtic feet 		= 	1 megalithic yard, 829 mm, 2½ megalithic yards	= 	1 megalithic rod, faethm. 33 megalithic rods	= 	1 furlang, 68.4 m, Md, 33 megalithic dods 	= 	1 country mile,, 2.257 km 2½ country miles	= 	1 megalithic league, 5.64 km — Preceding unsigned comment added by Telane5 (talk • contribs) 07:02, 3 November 2011 (UTC)

Arguments for a Geometric Derivation
Some commentators upon Thom's megalithic yard (John Ivimy and then Euan Mackie ) have noted how such a measure could relate to geometrical ideas found historically in two Egyptian metrological units; the remen of about 1.2 feet and royal cubit of about 1.72 feet. The remen and royal cubit were used to define land areas in Egypt: "On documentary and other evidence Griffith came to the conclusion that the square on the royal cubit was intended to be twice that the square on the remen; and Petri identified the remen as a length of 20 digits".

A square with side length equal to the diagonal of a square with side length equal to one remen has an area of one square royal cubit, ten thousand (a myriad) of which defined an Egyptian land measure, the setat. [cite mackie] John Ivimy noted that "The ratio MY : Rc is SQRT(5) : SQRT(2) to the nearest millimeter, which makes the MY equal to SQRT(5) remens, or the length of a 2 x 1 remen rectangle." ), see figure below. The main weakness in this argument is probably that the builders of the megalithic would have needed the remen and royal cubit, upon which this geometrical relationship relies numerically, to derive their yard.RichardDHeath

Possible Astronomical Origins
There is a simple explanation for the existence of the megalithic yard as being important to Megalithic Astronomy, if that astronomy counted days using a standard unit. The found difference between three solar years [1095.75 days] and three lunar years [1063.1 days] is 32 and five eighths of a day, which lies within the numeric range of the megalithic yard in inches, if valued at 2.72 feet long.

In 2010, a monument was found [Le Manio Quadrilateral] near Carnac, in which a three year count is to be found expressed in day-inches, using a right triangle between the summer solstice sunrise alignment and a long kerb of 36 to 37 stones, the number of lunar months over three years of either sort.

Since the inch is still a current unit of length, this implies that the thumb's breadth was simply standardised in the terminal Paleolithic, which was already counting the days, with uneven marks, of lunar visibility and even solar years according to Alexander Marshack. Adopting a standard length per day enabled the comparison of lunar and solar year lengths, to derive the megalithic yard over three years.RichardDHeath for review

As Architectural Unit in Pre-Columbian Mexico
Alexander Thom's megalithic yard emerged because he sought the type of metrological unit necessary for building large and complex buildings, which some megalithic structures are. A recent similar effort was made to find the principle unit of measure employed when building some or all stages of the pre-Columbian City of Teotihuacan, in the Basin of Mexico.

In Colin Renfrew's compendium The Archaeology of Measurement, Saburo Sugiyama published Teotihuacan city layout as a cosmogram (page 130). He had previously studied (1983) the dimensions within the Feathered Serpent Pyramid [FSP]. He says "my search for the TMU [Teotihuacan Measurement Unit] began at the main sculpted façade of the FSB" and "These data from the FSB led me to suggest that a unit of 83 cm was used at Teotihuacan". His TMU of 83 cm [2.723 feet] is very close to the nominal length given by Thom for the megalithic yard as 2.72 feet (see above).

Sugiyama then proposed in The Archaeology of Measurement that many lengths within the city relate to the Maya calendar, the astronomical period called the eclipse year [of 346.62 days] and sacred calendric period the Tzolkin [of 260 days]. For example, on page 144, figure 11.9, he deduces a distance between the centres of the FSP and Sun Pyramid based on the survey by Million et al. [1973] as being 1194.99 m which would be 1439.75 (probably 1440) of his TMU of 83 cm. Some other definable lengths within the city gave similar numerical results of nearly-whole and significant numbers of TMUs. He thus suggests a unit equal to the megalithic yard was used in pre-Columbian Mexico, though Sugiyama sees no parallel between his TMU and the megalithic yard.RichardDHeath for review

The Folkton Drums
Which according to a December 2018 Paper were a Neolithic standard measure of a 'Long Foot' of 0.322 mt, which would make a Neolithic Yard 0.966 mt vs Thom's Megalithic Yard of 0.83 mt. See https://www.dailymail.co.uk/sciencetech/article-6519551/Ancient-Stone-Henge-cylinders-used-tape-measure.html 86.187.174.0 (talk) 23:50, 21 December 2018 (UTC)

A Dual Unit System?
G.J. Bath suggests that the megalithic yard may well appear on stone circle diameters as a result of there being a pi-related unit on the circumference, that is, should there exist a multiple of such a unit that is 2.6 metres then the megalithic yard, since it is 2.6m divided by pi, would frequently and automatically appear on diameters whether it was put there or not.

He then presents an argument that this circumferential unit appears to be 162.8mm (6.4 inches) being one-sixteenth of a megalithic yard multiplied by pi, noting from some 300 surveys that the circumference of nearly every stone circle appears to be a multiple of four such circumferential units - meaning that the diameters would be multiples of one-quarter of a megalithic yard.

He argues that if the gaps between stones were intended to be a whole number of such a circumferential unit then it can be seen that the megalithic yard varies by 2% either side of the mean (829mm, 32.6 inches) across Britain and Ireland, far greater than Thom declared - and as Clive Ruggles suggested might be the case.

An introduction with illustrations can be found at:

A Circumferential Unit and Subdivision of the Megalithic Yard

For information only, as the work cannot be mentioned in the main article. ByNote (talk) 23:57, 26 October 2019 (UTC)


 * you're right that we can't use it. It's aimed specifically at fringe researchers, see its description under its original name here. It's self-published by KeyPress Ltd which seems to operate from his house. You're new so you may not know that article talk pages aren't meant to be places to discuss the subject, only the article.  Doug Weller  talk 08:09, 27 October 2019 (UTC)