However implausible it may seem to claim that we can make such a precise statement (overlooking small uncertainties in the azimuths) about a monument that has left hardly more than two-dimensional traces of its existence, there is much circumstantial evidence for our conclusion, as will appear in the course of the following suggested reconstruction of the procedures adopted by its builders:
The holes were prepared for the split trunks N and S, and N was erected. Scaling posts were set up at D and A, aligned with the eastern edge of N on the star Deneb. (Post d was also used along the same line, but for mechanical reasons and not geometrical, so that here it will be passed over in silence.) The opposition of Aldebaran’s setting and Altair’s rising was well known at the site, as was the fact that their directions over a natural horizon were almost perfectly at right angles to the Deneb line. Post B was set up to provide the requisite Aldebaran—Altair line. Some fine trimming in the position of A was needed, hence the oval hole. Post C was next placed so that it yielded a right-angle DCB, needed for the ‘viewing at right angles’ rationale of the monument. Once the lines of the artificial horizons had been so defined by the scaling posts AD and BC, the experimental part of the operation began. Beams were tied across those posts (see Fig. 18), the first of them perhaps to d too, and carefully adjusted in level and height (always kept equal) so that the rising of Spica and the setting of the Pleiades was always viewed across them at right angles. This was easily arranged: they simply used the uprights, C with D and A with B, to define the direction in conjunction with the appropriate beam. But viewing now had to be precisely done from a definite height, ground level, and the ditches were dug accordingly. Viewing was later going to be by people standing more or less in the ranges UV and XW of the ditches. The UV area was dug first, and the ditch extended to a point (E) suitable for observing the Pleiades. There was to be no wasted effort: digging was to be done as far as was needed, and no further. The same was true for a point G in the western ditch. (But later the ditch was extended to F so that an overland sighting of Spica was possible.) Care was needed to ensure that E and G were at precisely the same distances from their respective beams. At last the requisite height of the beams was found (it was about 1.09 m above eye level), and the roof of the mortuary house could be erected.
This was in the first place a wooden structure, and its being pitched would have aided the run-off of water, although it was only at a shallow angle of 10° or so. The perfect pitch for observing the stars was 10.4°. It was the two edges that were really crucial, and these were defined by marks cut into the split trunk N and by the short posts flanking S. These short and puny posts did not bear any load: they were levelling posts, each hammered into the chalk until level with the edge of the corresponding beam. The nearby sarsens bore the weight of the roof ridge.
By an unhappy circumstance—heavy sarsens in the ditch-fill—the inner ditch sections were not always excavated to the bottom, and never where they are of greatest interest to us. However, the inner ditch gives every sign of having been a normal viewing ditch, flat-bottomed and within a few centimetres of 1.65 m below the thin chalk soil (rendsina) under the cairn. (The estimated heights of eight adult males in the tomb yield an average of 1.70 m, and the average eye-level of the tallest three would have been about 1.65 m.) This has important implications for the astronomical argument. Clearly the remnants of the later cairn must allow for the idea that the viewing angle did not greatly differ from 10.4°. This they do, but the two sarsens at the southern D-post—which on our reconstruction supported the roof of the earlier wooden chamber—if set upright in the (known) stone holes from which they came, set a more reliable criterion. Each would have been almost exactly 1.05 m above the floor. The viewing angle requires the ridge at this point to be a minimum of about 1.20 m, and for more comfortable viewing 1.30 m, so that there is ample leeway for a (probably solid) roof of 15 or even 20 cm thickness. Trunks of this diameter could have provided a frame for the roof, bringing it up to the right height. The need for waterproofing might be thought to argue for a covering of turf or even compacted chalk, but solid trunks, split, trimmed to shape, and calked in some way would have been better.
The shallow ridge of the roof runs from K to I. What might easily have been taken as a sign of incompetence on the part of the builders, who might have been thought simply incapable of positioning one massive trunk precisely opposite another, is now on the contrary seen as testimony to genius of a high order. The trapezium outline of the horizon-roof is very much the same as the shape of the later long barrow, and no doubt its pitches were much the same. Furthermore, there is an exact analogy between the placing of the stone mortuary house within it, to the side of the central line, and the mortuary house under the roof between the split trunks (compare Figs. 13 and 19). In other words, the great barrow at Wayland’s Smithy was very probably a replica of that original roof, in all but the fine details of the angles, which the precession of the stars had altered.
The observing ditches were dug so that the ranges XW and UV were equidistant from the roof edges, just as G and E had been from their beams. Each range had space for six or seven people standing side by side. (Could they have been three men and three women, like the sarsens fronting the barrow?) Each person probably had a place-marker, say a ridge cut in the chalk. Note that the chalk at X was dug so as just to accommodate a viewing position, but with little more expenditure of energy than was necessary. Later extensions to the ditch took it up to other viewing positions L, M, and Q—and again took it no further than was necessary—from which the stars under discussion here could have been seen in different ways. Which stars they were will be appreciated without further comment, if Fig. 18 is examined for parallels to the lines of sight already discussed.
In possession of our several new principles, it is possible to re-examine the first chamber at Fussell’s Lodge, here previously dated at around 4235 BC on the basis of individual stars—Aldebaran, Spica, beta Crucis, and beta Centauri. The broad principles embodied in the use of scaling posts, whose positions are at Fussell’s Lodge known fairly accurately, are now taken to be the same as at Wayland’s Smithy; and these provide a pair of directions, across which it will be supposed that viewing was at right angles. Examining them for stars at low altitudes, no qualifying pair emerges at all, but as the altitude is increased it becomes clear that the setting Arcturus to the north8 and the rising Betelgeuse or Bellatrix to the south9 are possible candidates.
FIG. 20. Two possible forms of roof for the Fussell’s Lodge mortuary house, seen from different viewpoints. The first form, anticipating the shape of the barrow, is favoured here.
Although they are similar, the mortuary houses at the two sites differ in ways reflected in the final forms of their associated barrows. First, it seems that one of the right angles within the quadrangle of scaling posts is exactly as before, but that the other is not. It seems to have been drawn to the axis, and perhaps relates to a post in Ashbee’s ‘Pit III’ at the centre of the four. Second, the Fussell’s Lodge example is not itself plainly associated with a pair of viewing ditches and there was certainly none for use with the scaling posts. As for the way they functioned, much the same procedure could have been followed as at Wayland’s10.
FIG. 21. Potential right angles in the (highly stylized) forms of the barrows at Fussell’s Lodge and Wayland’s Smithy, drawn to approximately the same scale.
Again