In a previous article, the 7,500 foot-long Erdevan alignments were seen to have been a long count of the Saros period of 19 eclipse years versus the distance to Mane Groh dolmen of 19 solar years, this probably conceptualized as an 18-19-6 near-Pythagorean triangle, whose inner angle is the bearing from east of Mané Groh. However, the path directly east caused the actual alignments, counting the Saros, to veer south to miss the hill of Mané Bras.
It has been remarked that the form of the northern alignments of Edeven were similar
to those starting at Le Menec’s egg-shaped stone circle 4.25 miles away, at a
bearing 45 degrees southeast. Whilst huge gaps have been caused in those of
Edeven by agriculture, the iconic Le Menec alignments seem to have fared better
than the alignments of Kermario, Kerlescan and Petit Menec which follow it
east, these being known as the Carnac Alignments above the town of that name.
One similarity between alignments is the idea of starting and terminating them with ancillary structures such as cromlechs (stone kerb monuments), such as the Le Menec egg and, despite road incursion, a3-4-5 structure similar to Crucuno, aligned to the midsummer sunset by a length 235 feet long. This is the number of lunar months in the 19 year Metonic period and is factored 5 times 47. Another similarity may be seen in Cambray’s 1805 drawing of these Kerzerho alignments, at the head of ten stone rows marching east (figure 1).
The word Alignment is used in France to describe its stone rows. Their interpretation has been various, from being an army turned to stone (a local myth) to their use, like graph paper, for extrapolation of values (Thom). That stone rows were alignments to horizon events gives a partial but useful explanation, since menhirs (or standing stones) do form a web of horizon alignments to solstice sun and to the moon’s extreme rising and setting event, at maximum and minimum standstill. At Carnac the solstice sun was aligned to the diagonal of the 4 by 3 rectangle and maximum and minimum standstill moon aligned to the diagonal of a single or double square, respectively.
It seems quite clear today that stone rows at least represented the counting of important astronomical time periods. We have seen at Crocuno that eclipse periods, exceeding the solar year, are accompanied by some rectalinear structures (Le Manio, Crucuno, Kerzerho) which embody counting in miniature, as if to record it, and it has been observed that cromlechs (or large stone kerb monuments) were built at the ends of the long stone rows of Carnac and Erdeven. Sometimes, a cromlech initiated a longer count,with or without stone rows, that ended with a rectangle (Crucuno). The focus on counting time naturally reveals a vernacular quite unique to this region and epoch. We have seen that the Kerzerho alignments were at least a 4 by 3 rectangle which recorded the 235 lunar months in feet along its diagonal to midsummer solstice sunset. After that rectangle there follows a massive Alignment of stone rows to the east,ending after 2.3 km having gradually changed their bearing to 15 degrees south of east. Just above the alignments lies a hillock with multiple dolmens and a north-south stone row (Mané Braz) whilst below its eastern extremity lies the tumulus and dolmen,”T-shaped passage-grave” (Burl. Megalithic Brittany. 196) called Mané Groh.
In 1973, Alexander Thom found the Crucuno rectangle to have been
“accurately placed east and west” by its megalithic builders, and
“built round a rectangle 30 MY [megalithic yards] by 40 MY” and that
“only at the latitude of Crucuno could the diagonals of a 3, 4, 5
rectangle indicate at both solstices the azimuth of the sun rising and setting
when it appears to rest on the horizon.” In a recent article I found metrology was used between the Crucuno
dolmen (within Crucuno) and the rectangle in the east to count 47 lunar months,
since this closely approximates 4 eclipse years (of 346.62 days) which is the
shortest eclipse prediction period available to early astronomers.
About 1.22 miles northwest lie the alignments sometimes called
Erdeven, on the present D781 before the hamlet Kerzerho – after which hamlet
they were named by Archaeology. These stone rows are a major complex monument
but here we consider only the section beside the road to the east. Unlike the
Le Manec Kermario and Kerlestan alignments which start north of Carnac,
Erdevan’s alignments are, like the Crucuno rectangle accurately placed east and