Stonehenge Solved Its Three Observatories, Who built them, How and Why

The speculation continues. The hosts suggested they first consider sites at the settlement, known today as the Northern and Southern Circles, Fig 24, and then, in the light of what the visitors had told them, move on to others further afield (i). Their ancestor's observations of the apparent paths of the Moon prevailing in their day, were initially made by watching the movement of shadows cast by pointed stakes driven into the ground at random; also those of poles, the butts of which were secured in holes by the backfill. These were only suitable for high angles of elevation, and in any event soon became unstable. Subsequently they utilised short baulks of timber, that is to say smoothed limbs, cupped snugly in ramps cut into the lips of pits, the baulks being orientated to low angles of elevation around the horizon. The shadows were cast on the smoothed near-vertical side of the heap of backfill holding the baulk in place. This arrangement was more stable but suffered loss of effectiveness from mists and was very difficult to adjust. These were followed by a more sophisticated use of ramps at a site a few metres south of the settlement: ring B at what today we know as Woodhenge, Fig 25, (ii). The hosts' own recent attempts at high angle observations were made at ring E, Fig 26.

The Egyptians reacted in two ways. Firstly, they were intrigued by the arcs of the Moon's paths; they were a strange phenomenon to them and they surveyed them for themselves in ring C at Woodhenge, Figs 27, 28, 29. They too, confined themselves to the southwest sector, their notional bisector being 237.5 degrees, and created a means of fine adjustment at 5 degree steps in the angles of elevation, ranging from 18 to 43 degrees. Secondly, they were appalled by the low level of technology which limited the methods of observation to holes in the ground and consequently to short shadows. These in turn inevitably led to coarse reflections of changes in angles. They pointed out that by using their arrangement of ring A, where a spar impaled by two flints was suspended from a crossbar by improvised plaited creeper stems, they could dispense with fixed position ramps, Fig 30. Additionally, they could observe the Moon in daylight as well as at night, by sighting the notional centre of the Moon, whatever its phase.

In the absence of rope, which was unknown them, the Britons were skilled at making lines of creepers for their dwellings, and what they needed to do was make them thicker and stronger. "Of course, the arrangement would be more stable and durable if made of stones and rope", the Egyptians may well have said. This was the signal to leave and journey to inspect the installations 27km (17m) to north, talked about on their arrival.

The Egyptians had already been told of the damage wrought by rare but catastrophic floods, and of a huge flood refuge, conical in shape, and created with chalk dug close by. We call it Silbury Hill, Figs 31, 32, 33 (iii). The level of a recent flood had exceeded expectations and the local populace was in despair because they could not see how to raise its height still further without collapse. This was the situation when the researchers arrived on the scene when only a few kilometres short of Avebury, their ultimate object of interest. The Egyptians told them how it could be done: with an ascending series of chalk block walls, but its execution was beyond the skill of the local people.

The installation at Avebury fascinated the visitors, Figs 34, 35, (iv). Where at Carnac they had achieved a lengthly sight line by erecting a tall, vertical foresight, here it had been done horizontally by employing upright stones round the inner rim of a large ditch: the Moon throwing the shadow of a stone's top on to the sloping ditch flank opposite. The arc of the ditch approximated to a quarter of a notional crude circle. Built in three phases, the arcs of the first phase had a distance of about 11m (36 ft) between fore and backsight, the second 24m (80ft), the third saw the addition of a deep surface water drainage ditch (v). Of greater interest to the visitors were the stones themselves; some stood on their ends, others on a corner and none of them was fashioned, they were all in the rough state just as they were when found at the quarry. There were 98 in all, (with one or two located altogether out of the general lines) but to these could be added dozens more which delineated two avenues disappearing through the scrub into the distance. It was apparent that the maximum attainable heights of stones had often being sought, by standing them on a corner, particularly when a stone was wide and relatively short. This was done for a better positioned shadow on the flank of the ditch, and for improved visibility across the prevailing scrub when demarcating the margins of the avenues.

Where did the stones come from and how were they moved, they wanted to know. The visitors were taken 12km (8m) northeast of Avebury to the Marlborough Downs to see hundreds of huge rough stones of all shapes and sizes, today called Sarsens, strewn over a large area. Incredibly here and there were balls of the same stone, a phenomenon to be seen in their own country, and effective when used as mauls for working and making smooth, rough stone surfaces. It is speculated they witnessed the exploitation of the inexhaustible availability of huge trees. After felling a tree, a fork, created by a lower limb, was axed out and fashioned into an 'A' frame, Fig 36. This had flat, level and smooth under-side surfaces, a generously rounded nose, and a bracing crossbar, the whole serving as a sledge. In many instances, a quarried stone, (stones were lying about on the surface) was mounted cross-wise on it. This was done firstly, by digging a shallow under-pass in the chalk beneath it leaving it supported at each end. With the frame positioned under the stone, the ground was removed each side so that the stone subsided on to it, ready for removal. The assembly was then manoeuvred along a spontaneously created short 'feeder' route towards the start of a trackway running between the quarry and Avebury. This trackway was formed by removing say, a 3m (10 ft) wide band of turf to expose the underlying chalk and occasional subsoil. The assembly was eased along this by levers applied to the stone by men on the turf each side, chanting and moving in unison as they worked.

A more complex task was raising the stone to be vertical on its intended site. The means for doing this needed to suit the many diamond shaped stones to be stood on one corner. Having nothing but trees of all sizes, including enormous ones, and axes, the 'law of the lever' was employed in a progressive fashion. That is to say big levers were manipulated by smaller ones, and so on in turn, with fulcrums. The huge weight of a tree stem could be employed as a counterweight to a stone. Movements were incremental, positive, slow, controlled and precise. These principles enabled turning massive stones through 90 degrees from horizontal on the 'A' frame, to vertical, without the use of rope, which had not been invented in Britain by then anyway. Nevertheless the detail of the method employed is not obvious, and needs to be thoroughly worked out in theory before any scaled, practical re-enactment is attempted. (see chapter 15)

Besides strong and competent workers the Egyptians had all but found the stone they would want, were they to contemplate constructing a design they had in mind, but not quite. There were no small stones, of which they would need very many, some as construction equipment, and the stone they had seen was not amenable to being broken into suitable small pieces. They would also need a large quantity of rope, much manpower, and a suitable site. The conversation was now animated. For the smaller stones they were describing, the Britons said they knew of a huge supply, ready made, but it was a great distance away to the west near the sea (vi). The response to that was: if Britain is an island, as they said, it could be visited on their way home, if the accompanying Bretons could tolerate the diversion, and if a small party of Britons would guide them to the quarry and be prepared to sojourn in Carnac thereafter.

As for the rope required for the design of installation they had in mind, the Egyptians said they could only return with a small quantity, so in the meantime their hosts would have to grow lots of flax, and trade for it; they would show them how to convert it on their return. The question of their hosts manning the installation when completed, so that the Egyptians could receive reports of findings about changes in the Moon's paths, was soon resolved. They would convey the results to Carnac for the quickest possible retrieval by the visitors. Construction manpower was another matter: their hosts, and the Bretons, would all contribute, and so would the people of Silbury, provided they could get on with augmenting their refuge according to the Egyptians' design, and with their immediate supervision, until it was finished. The deal was done.

On their way back to Durrington Walls the choice of a suitable site was indicated when the Britons said they knew of one near at hand. Upon their return they inspected a flat, almost level, circular site some 90m (300 ft) in diameter, only 3km (2m) away to west southwest: the overgrown vestiges of the Early Henge. Not only was it readily accessible from Durrington along a connecting straight way, it was on high ground, safe from flooding; its only slight drawback was a close horizon on the south and southwest, all other views were clear.

The Egyptians sketched outline plans of the structure they had in mind and thereafter, accompanied by some of their hosts, returned to their ships. After reminding them about the need for flax, they bade them farewell and set sail for their exploratory voyage westwards, with a small party of Britons and the homeward bound Bretons on board. They rounded Lands End and followed the south, and then the north coast of the Bristol Channel and entered Milford Haven, proceeding up its entire length until beaching at Eastern Cleddau. From here they walked 25 km (16m) northwards to reach the Presceli Hills and discovered masses of so called Bluestones in all sorts of sizes, variously laminated by weathering and ready for use, many without fashioning (vi). While assessing their suitability they noted the sea could be seen and found it was only 16 km (10m) distant, downhill all the way to Newport Bay Sands. Bidding farewell to the Britons, with the Bretons they retraced their steps to the ships and sailed home, calling in once more at Carnac.