Anne Macaulay was primarily a musicologist, mathematics and music being sister and brother. Her starting point was the inspired recognition that the Pythagorean mathematics which apply to the tuning of the ancient Greek lyre, the 'cithara', the predecessor of the guitar.
In the late 1950's her creative energy was rekindled by an intense interest in classical guitar music. She learnt to play the instrument and attained a proficiency considered close to that of a virtuoso. After a frozen thumb put an end to her playing the guitar her obsession with the instrument's early history continued. She was also obsessed with Apollo, the god of music and healing, and why he was associated with the lyre. In an inspirational moment, she married numbers to the to the letters of the Greek alphabet for the name 'Apollo'. She discovered the geometric figure whose proportions are to be found in the layout of many megalithic stone circles and from which a guitar may be tuned.
When Anne Macaulay began her researches she had no intention of entering the areas concerning Apollo and religion. She started by exploring the history of the modern guitar with the intention of discovering where it had originated from. She found that the guitar was derived from the cithara, the seven stringed lyre, an ancient Greek instrument that had been invented by Apollo. She declared that music can be seen to be an integral part of Pythagoreanism: using standard archaeological methods, along with the music, all the "tools" of the Pythagorean culture were considered together, which led back in time eventually to the source of Apollo in the West of Europe in the megalithic period.
The starting point for Anne Macaulay was the study of ancient Greek musical scale. Macaulay argued that the musical side was essential to unravelling these mysteries, in the first instance because the music defines the background to the whole culture in time and space, secondly it demonstrates the relation to Pythagorean geometric practices, and finally demonstrating how the extreme West of Europe are still strongly connected to these ancient roots.
She pondered that there must have been a common cultural source that flourished around 1450BC which gave the same cithara instrument to both the Greeks and the Hyperboreans in the West of Europe. Before this time there were many civilisations in Egypt and the East but in none of these places was found either the cithara or the god Apollo. Apollo was thought to have come from the North, his mother Leto born on the Island of the Hyperboreans, which many have proposed as Britain. The appearance of Apollo's lyre in Crete in around 1450BC coincides with the time that Stonehenge along and some other megalithic sites were abandoned. Macaulay declares this as the end point of a long and brilliant megalithic period which had lasted nearly three thousand years in the West of Europe. It was beginning to look like the cithara, which existed in the West before the Greeks, the god Apollo and the Pythagorean way of thought all came from the megalithic culture of Western Europe.
The account of Hecataeus, and later quoted by Diodorus, retells how he was told in Hyperborea that Apollo had been born in their land. The limiting date of 1450BC coincides with the abandonment of Stonehenge and the presence of Pythagorean-type geometry found in the megalithic rings as demonstrated by Alexander Thom who proposed that many of these ancient British sites are devised from a starting point of one of the Pythagorean right-angled triangles at the centre, most often this being the 3:4:5 triangle.
If Apollo was known in Minoan Crete, then the date of his birth in Hyperborea must antedate the appearance of Apollo in Crete, which cannot be later than 1450Bc. This placed Apollo firmly in the megalithic period. It is known that Apollo was equated with the sun and his twin sister with the moon, Macaulay suspected further proof could be found in the many megalithic sites which were used to define calendrical dates from astronomical events.
Two significant astronomical events, the first again Diodorus quotes from Hecataeus, who had arrived in Hyperborea in time to find the priests celebrating the return of Apollo at the end of the 18.5 year lunar (metonic) cycle. The second event is the reference to Apollo leaving Delphi in the autumn to spend the winter in the land of the Hyperboreans, returning once more in the spring. Macaulay realised that as Apollo's main attributes were the swan and the lyre, that these travels refer to movements of the constellation Cygnus, the swan, and its neighbour, the constallation of the Lyre, which are only visible in the Greek world in the summer, but circumpolar in the North and therefore visible all year. Furthermore, Macaulay states that the Apollo geometry is related to astronomical events associated with the god in ancient times, the circumpolar stars being the most sacred and defined by the pi circle. She concluded that Apollo is the name derived through the sacred numero-geometric alphabet from a geometric figure which was itself derived from astronomical observations of the circumpolar stars and the moon. 
In summary, Colin Wilson states: “Macaulay is suggesting that the phonetic alphabet series was created as a mnemonic aid to record the positions of the polar stars, and that the word 'Apollo' - the god of music - was one of these basic mnemonics. The letters, from A to U, were created as mnemonics for certain geometric theorems or figures, with which numbers were associated. But Anne Macaulay draws one thought-provoking conclusion: that when this 'code' is used to encapsulate the extreme southerly rising of the moon, the ideal place to build an observatory is precisely where Stonehenge is placed. Another is that all this indicates that ancient Greek science - including Pythagoras (who born around 540 BC) - probably originated in Europe - the exact reverse of a suggestion made in nineteenth century that Stonehenge was built by Mycenaeans. She suggests that the early Greeks may have been British tin traders from Cornwall........The importance of this whole argument is its suggestion that geometry and astronomy existed in a sophisticated form long before there was an accurate method of writing it down. Anne Macaulay believes – as Thom does – that it can be read in the geometry of megalithic circles and monuments.....” 
1. Apollo: The Pythagorean Definition of God by Anne Macaulay, from
'Homage to Pythagoras: Rediscovering Sacred Science', Lindisfarne Press, 1994. [Left]
Anne Macaulay's article, Apollo: The Pythagorean Definition of God, originally appeared in Lindisfarne Letter No 14, 1982, Papers from the 1981 Lindisfarne Corresponding Members Conference, Crestone, Colorado.
2. From Atlantis to the Sphinx - Colin Wilson, Virgin Books, 1996, pp 212 – 213. Wilson states it was Keith Critchlow (Time Stands Still) who introduced him to the ideas of Anne Macaulay who was in turn was kind enough to let him read the unpublished manuscript of her book which then had the working title of Science and Gods in Megalithic Britain.
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