I’ve posted previously on the subject of the Aubrey Circle – it’s worth bearing in mind that David Kenworthy has shared a wealth of information on the subject on various forums – The Megalithic Portal, GHMB, Ancient Measures/History of Metrology, and The New Metrology, not to mention a series of painlessly priced e-books available from Amazon. DavidK has an impressive grasp of the subject, and an impressive interpretation of the Aubrey Circle that merits serious consideration.
Nonetheless, the subject of the Aubrey Circle may still be up in the air. There are the aforementioned differences in Thom’s data over the course of several books, and things may become even more complicated from there in trying to corroborate the proportions given.
Reviewing Thom’s remarks accompanying the later, smaller measures may hint that the smaller measures derive from radial measures and extrapolating circumference from them, and the earlier, larger measures may originate from multiplying the mean distance between adjacent Aubrey Holes by the number of holes – a mean value that may be somewhat skewed because of the uneven spacing of the holes – although I am unable find materials where there this is clearly explained.
Indeed, in the later work (Megalithic Remains in Britain and Brittany), Thom states
“It thus appears that the holes were more accurately placed radially than circumferentially”.
However, this isn’t entirely clear in its meanding. In MRIBAB, Thom refers back the the statistical methods described in the earlier work, Megalithic Sites in Britain, which may not have considered the spacing between adjacent Aubrey Holes.
The chapter in the later work on Stonehenge is essentially the same as Thom’s work on Stonehenge here, but with some differences. At the link, on page 82 we find the comment referenced directly to page 35 of Megalithic Sites in Britain, but this still seems to tell us little about the difference in methodology that resulted in two distinct sets of figures, and Thom’s comments at the link refer to only partly using data from Atkinson.
It’s my belief that both figures given by Thom are meaningful and both are obtained in legitimate and intended ways, but I essentially have no data on the spacing between adjacent holes to try to confirm Thom’s figures with. (Thom also refers in places to what sounds like a preference for measuring the inner diameters of circles).
The only data set I have that seems to attempt to distinguish between minimum and maximum diameters is that shared by Richard P. Bartosz (Orpbit) in the tables posted to his thread Stonehenge Measurements at the Megalithic Portal, which Peter Harris has recently called further attention to in the HSMF thread there.
DavidK sometimes refers to this data set as well as Thom’s earlier data for support for his Aubrey Circle assessment. This dataset seems as if to corroborate Thom’s data except for the matter of which circumference value is referred to – here the outer diameter for the Aubrey Circle 285.7353 ft x Pi = 897.6639194 is very close indeed to David’s 897.6 value, except that here it is a maximum value while it may be doubtful that Thom gave a maximum as opposed to a minimum or mean value.
There are a number of interesting things about the data presented by Orpbit (and for the most part his data for the sarsen circle, including the mean, is sufficiently and encouragingly harmonious with standard sources).
Note the inner diameter for the Aubrey Circle, 278.5989 ft. 278.5989 x Pi = 875.2442575 ft circumference. Also, the mean diameter given, 282.1671 ft, is suggestively close to the reciprocal of the Lunar Calendar Year. Using my standard figure, 353.9334578 representing 354 days, 1 / 353.9334578 = 282.5389852 / (10^n) = 887.6223994 / Pi.
278.5989 is suggestive of 278.8548009, a fairly underappreciated number which is often overshadowed by a similar figure, the projected height of the missing apex section of the Great Pyramid, 279.4546572 / 10.
sqrt 77760 = 278.8548009, and six to the fifth power (6^5) = 7776. 2.788548009 is the only value I’ve ever seriously considered as possibly being the intended value of the Spanish Vara, since it’s one of few values slightly larger than the Megalithic Yard whose mathematical properties might justify its adaptation as a metrological unit. However, metrologically, 2.788548009 may be the same thing as the Thom Mid-Clythe Quantum, which I’ve proposed is sqrt 60 ft. 278.8548009 / sqrt 60 = 36.
278.8548009 x 2 = Munck’s “Giza Vector” number (the square root of 311040) and 278.8548009 x 4 = 1.115419204 x 10^n. 1.115419204 is an important number that was mentioned yet again very recently, including a possible newfound geodetic function in conjunction with a Megalithic Foot
A minimum diameter of 278.8548009 would give a minimum circumference of 876.048194 feet = 720 Remens of 1.216733603 ft each.
278.8548009 as a minimum value and 282.5389852 as a mean value would give a projected maximum of 282.5389852 + (282.5389852 – 278.8548009) = 286.2231695 ft (data 285.7353) = 899.1966066 ft (data 897.6639194 ft) circumference . While the projected circumference varies notably, the adjustments to the mean and minimum diameter values on which is based are relatively negligible.
899.1966066 is sufficiently accurate as an approximation of 4 times the Venus Cycle to pass the “Giza Standard of Accuracy” test (.9995 or higher).
224.8373808 x 4 = 899.3495232 = 899.1966066 to an accuracy of 899.1966066 / 899.3495232 = .999828057.
An interesting thing is that these suggestions are linked together in a series by the Pi ratio.
876.0481940 / Pi = 278.8548009
278.8548009 / Pi = 887.6223994 / 10
887.6223994 / Pi = 282.5389849 / 10
282.5389849 / Pi = 899.3495214 / 100
(876.0481940 times Pi = 2752.186570 — in Imperial Feet, 10 times the radius of Silbury Hill in my models). 8760.481940 is the number of hours in a calendar year of 365.0200808 (300 Remen) days. 365.0200808 x 24 = 8760.481940.
These suggestions and their possible progression are also very reminiscent of the first table here, showing the metrological projections of a series of circles that is based on the most prominent value approximating the number 56 (the Aubrey Circle being noted for its 56 Aubrey Holes), seen in the first table here.
| Radial Value | x 2 Pi = | Circumferential Value |
| 1.789199019 = 1 / 5.589093161 = Aubrey 56 #1 | x 2 Pi = | 1.124186899 = Petrie Stonehenge Unit / 2 |
| 1.124186899 | x 2 Pi = | 7.063474605 = 6 x 1.177245771 = ~6 HSMF |
| 7.063474605 | x 2 Pi = | 4.438111985 = SRVS / 2 |
| 4.438111985 | x 2 Pi = | 2.788548002 = Vara? |
| 2.788548002 | x 2 Pi = | 1.752096383 |
| 1.752096383 | x 2 Pi = | 1.100874625 = Indus Ft |
Note that the proposed value for Athanasios Angelopoulos’ Megalithic Cubit should be added to the first space of the table, since 17.89199019 / 12 = 1.490999190, my suggested value in feet for a Megalithic Cubit.
SRVS in the table refers to 887.6223994 which we have just seen in the suggestions from the Aubrey data. 887.6223994 is the Square Root of the (generic) Volume of a Sphere, based on making the spherical radius the Radian value of 57.29577951.
Please note also that 6 putative Megalithic Feet (7.063474605 ft) and 1/200 of the Petrie Stonehenge Unit in inches also appear here. 5.589093161 / 2 = 2.794546580, so both this value (1/10 of the projected Great Pyramid apex section in feet) and 2.788548002 manage to find their way into the same progression, rather than overshadowing or excluding each other.
5.589093161 x 4 = 2.235637264 / 10. This is the approximation of the square root of 5 that links the Megalithic Yard to the Remen: 2.720174976 / 1.216733603 = 2.235637264. The Megalithic Foot converts this number to the C value for the Half Venus Cycle: 2.235637264 / 1.177245661 = 18990.40387 / (10^n).
1 Megalithic Rod of 2.5 Megalithic Yards of 2.720174976 ft = 6.800437440, and
6.800437440 / 1.216733603 = 5.589093161
18990.40387 is the Half Venus Cycle (Calendar Round) value that was introduced by Stonehenge and came from combinations of some of its most important numbers like 1.177245771, 1.216733603, and 1.067438159. It was soon found to be contained in the basic data for the Great Pyramid’s base length as well.
None of this necessarily excludes DavidK’s interpretation of the Aubrey Circle, or my own version of it, featuring “The Aubrey Number” that has proved to be fairly ubiquitous in data projections for ancient architecture. One presumes min, mean, and max values are also to be projected from Thom’s first data set, which supports this second interpretation, but it isn’t yet clear to me which exactly of these Thom’s data is supposed to represent.
I will note that some of the data for the Aubrey Circles projected from Orpbit’s data seems to resemble closely enough data from Cleal et al for the mean size of the Aubrey Holes (although like Spatzier publishing about Pommelte Henge, the mean values given by Cleal et al appear to be miscalculated, so this in reference to the corrected mean values for the Aubrey Holes based on their minimum and maximum values).
I am not yet aware of the provenance of the data beyond DavidK’s comments, but David has pointed out a second Aubrey Circle (Stukeley Circle) for which he asserts a diameter of 291.20 feet. I’m quite tempted to take this figure as possibly being 292.0160646 ft = 240 Remens, beginning with this being 1/2 of the standard approximation of the Venus Synodic Period to complement a number of references to the Venus Orbital Period through Stonehenge measurements and proportions
292.0160646 x 2 = 584.0321292 Venus Synodic Period
DavidK asserts that this second circle was associated with 52 postholes and has discussed the relationship between the numbers 52 and 56.
Two prominent approximations of the number 52 already appear in my model of Stonehenge – the maximum radius of the sarsen circle 51.95151515 ft, and the maximum radius of the lintel circle, 52.04568991 ft.
(292.0160646 x 10) / 52.04568991 = 56.10762563, which is one of the possible approximations of 56 used at Stonehenge. It is in fact 1/4 of 1/10 of the “Aubrey Number”. 56.10762563 x 40 = 224.4305025.
292.0160646 / 51.95151515 = 224.8373808 / 4 / 10.
These two resident approximations of 52 given can form 1/2 of the Squared Munck Megalithic Yard (the reciprocal of their product), and the prized Wonder Number and 2 Pi root 1.001812743 as their ratio, affording Stonehenge yet another luxury enjoyed by the Great Pyramid.
52.04568991 / 51.95151515 = 1.001812743.
The circumference derived from a perimeter of 292.0160646 x Pi = 917.3955233 ft which is 1080 Inverse Megalithic Feet. (1 / 1.177245771) x 1080 = 917.3955233.
It remains to be seen whether 292.0160646 x (52.04568991^3) = 411.6812176 represents a valid way of representing the Full Moon Cycle of 411.78443029 days.
7.909996358 x 10^n is also part of the same progression — 292.0160646 x (52.04568991^2) = 790999.6358. This is clearly a valid and relevant number since 5 / 7.909996358 = 316.0557713 / 500.
316.0557713 ft is the mean circumference of the sarsen circle in my Stonehenge model.
7.909996358 x 2400 = 18983.99126, Half Venus Cycle A.
This should alert us that this Half Venus Cycle value is contained in (and readily available from) the mean of the sarsen circle.
(60 x 10^n) / 18983.99126 = 316.0557713
These are all merely speculative suggestions as this point, but I like to think that when Mike Parker-Pearson or others suggest that the Aubrey Holes once held bluestones (Mike Parker Pearson, Stonehenge A New Understanding), that we can see well enough mathematically why these bluestones would have been relocated and not left in place – i.e., because the same data was being contained in a revised design so that they may have become obsolete.
–Luke Piwalker
Luke Piwalker 