Origins of Stonehenge - Appendix C

Appendix C

Dating the Y and Z holes

For a 'sunrise season/weather forecaster' theory to be valid, the Eastern Y and Z (Y&Z) holes arc must have been built before the Sarsen Stone structure as this blocks the view. So this is a critical point on which the theory could fail.

1) - Dating of Y&Z holes by Red Deer antlers

The assumption of the date of an inorganic structure (Y&Z holes) from the carbon dating of organic material found in them (Red Deer antlers, 1600BC) must be treated with caution as regular cleaning of the holes would remove earlier organic material. Thus the Red Deer antlers may indicate the date at which cleaning was abandoned - cleaning made necessary by debris and infilling from the winter storms. It does seem unlikely that having dug these holes with their nice clean white chalk bedrock bottoms they would then be left to silt up from the winter storms.

In addition there is no way of knowing how old the antlers were when placed in the hole, if they were preserved in a similar environment beforehand, in addition to not knowing how old the holes were.

There appears to be other organic material found in Z29 that place the date earlier.

( Source Wikipedia Y and Z Holes - first paragraph )

So there are doubts about the dating methods.

2) - Blocking of the Y&Z holes by fallen Sarsen

Figure 4.1 below shows that if the Sarsen stones arc chord of Y&Z holes had continued on the same radius (anti-clockwise) the fallen Sarsen would not have blocked the holes. If fact Z9 lies at the end of the fallen Sarsen, so there is no reason why the Y&Z holes should not have continued on the same radius to form a complete circle - as would be expected. The Eastern arc chord, if continued clockwise, would have extended beyond the midwinter sunrise point and even if there was no obstructing fallen Sarsen, would have coincided with an existing Sarsen stones ring, which would not be sensible.

Z12 appears to be partially covered by another fallen Sarsen, indicating that the Y&Z holes were built before the Sarsen stones began to fall into ruin.

Y8 is an oddity that appears to be an attempt to join the two displaced arcs chords ends together. I suspect a Z8 lies hidden under the fallen Sarsen, which would again indicate that the Y&Z holes were built before the Sarsen stones began to fall into ruin.

3) - Y&Z holes cutting into Sarsen stone erection ramps and post holes

The cutting into the stones ramps and infill can give two alternatives; the digging of a new hole, or the re-digging of an already existing hole. i.e. the stones are so long that they could have been slid across pre-existing holes (which are only 1 to 1.5 metres wide) and, after the in-filling of the ramps, would need to be dug out if the hole was to be part of the Sarsen stone structure. I am surprised that the ramp extended as far as Y2. It would be interesting to hear the views of the relevant archaeologists on this, and perhaps an explanation of why it is not possible ?

The cutting across post holes is something that I can find little information on, but again a redundancy of a post hole could result in the re-digging and use of an original Y or Z hole. The age of the post holes seemed to have been dated at 3000 BC, well before the stone structures.

4) - Obstruction of surveying by Sarsen stone structure

A further point that should be considered for the dating of the Y&Z arcs is that in order to construct the arcs they must have been laid out before the Sarsen stones erection, as these would obstruct the measurements and view from the origin of the arc. Furthermore, what would be the purpose of the Eastern arc, off centre to the Sarsen stones, which could not be used to view the sunrises progression in it’s entirety ?

For an illustration of the Y&Z holes positioning to the Sarsen ring please refer to Figure 4.1 below -

Figure 4.1 Y and Z hole Positioning

Figure 4.1 Y and Z hole positioning Y&Z holes in general indicating the obstructing presents of the stones is a very sound one, especially with regard to Y5. It can be seen that the Eastern arc is quite regular, with the exception of Y5. The Sarsen stone Y&Z holes arc is not nearly so regular with both the radius and arc chord length between adjacent holes varying.

However the sight line from the Eastern arc origin to Z5 and Y5 shows that the displacement is not as sever as first appears. There is a reasonable consistency of the accuracy of the sight lines along the three points of the origin of the arcs, and matching pairs of Y&Z holes. Please refer to Figure 4.2 below -

Figure 4.2 Sight Lines of Y and Z Holes

This consistency of sight lines makes it appear that a Neolithic surveyor (freeman) standing at the origin of the arcs shouted at two Neolithic assistants (slaves) to position them and mark the positions for the digging of the holes. This would explain (a) the irregularity of the arc chord length between adjoining stones, dependent on the surveyor’s judgement by eye, and (b) the irregularity of the radius if measure by leather cord, as the cord over this distance would be quite elastic. ( I know this as I used leather boot laces in the 1960’s army, and they are quite elastic, hence the comfort ) The sight line from the origin across a Y&Z pair would be easy to judge by eye and should be quite accurate, which it is.

It is difficult to understand how this accuracy could be achieved with the Sarsen stone structure present, as the stones would obstruct the sight lines, especially in the cases of Y6 and Y16. Thus the implication is that the Y&Z structure was built before the stones, with less developed surveying skills.

5) Survey Standards -

The construction of the Y&Z holes is not nearly as complex or accurate as the Sarsen stone structure, which implies an earlier date for the holes when survey skills and construction techniques were at an earlier stage of development. This however does assume a steady progress of developing skills, which is usual.

6) Markers in the Y&Z holes -

The edges of some holes are in a ‘slightly ruiness state’ which indicates they may have once held stones. Bluestone fragments have been found in the holes - markers for the midsummer and midwinter sunrises perhaps ?

Further Considerations

(a) No marking of the midsummer sunrise point -

As shown in Figure 4.1 above, the Eastern arc commences at the midsummer sunrise point as the divergence of Y&Z 29 and Y&Z 30 indicates. The construction line adjacent to the Sarsen stone ring makes this clear. The arc ends at the midwinter point. I have suggested that the Eastern arc was an original structure, and developed into a circular structure at a later date, well before the stone structures.

Once the Eastern arc had been extended into a circular structure, markers to indicate the midsummer point may have been used, of which some traces, as per the 'slightly ruiness' hole edges and Bluestone chips, have been found. The Heel Stone may date back to the construction of a circular structure to mark the midsummer sunrise point.

(b) Y&Z holes: a circle, spiral, or arc ? -

Attempts to impose a circle as in the Wikipedia diagram ( Y and Z Holes ) are not able to follow the holes as accurately as the arcs are. The Y&Z holes are not a circle or a spiral, they are two arcs. (as defined by maths geometric shapes) The Eastern arc is just too regular to be an accidental irregularity.

Some doubts about the positions of the holes have been raised by Field and Pearson in order to regard them as a circle. The doubts are based on Colonel Hawley’s ‘poor co-ordinates‘ for the present accepted diagram. However no definition for 'poor co-ordinates' is available, and no alternative diagram has been produced; and the regularity of the two arcs, especially the radial sight lines, rather discount this.

Colonel Hawley was a senior officer in the Royal Engineers, so would be more than capable of surveying work, although he did employ a professional surveyor. Robert Newall, his assistant, was a draughtsman from the Office of Works. So the required skills were available to produce professional work to a high standard.

Positioning the holes was done using the Ordinance Survey grid system, and applying a graph principle (as per Cartesian co-ordinates) This can be resolved down as far as accuracy requires. The limiting factor is the hand tools used for measurements. My agricultural apprenticeship in 1965 included a surveying course with the hand tools of a chain for linear distance, magnetic compass for North, and optical theodolites. An effective practical theodolite was available in 1787 ( Jesse Ramsden's ). These hand tools are surprisingly accurate for building civil structures.

With two axis marked out and a theodolite, the position of anything on that grid can be located and recorded as an x and y co-ordinate. An accurate diagram can then be drawn. The diagram Fig 151 in Cleal et al appears to have been done with some care and professionalism, as would be expected at that time.

(d) Stratigraphy Evidence -

Stratigraphy means strata (strat) positioning (graphy)

The principle that relative dating can be assumed by the position of material in vertical relationship to other material depends on a couple of assumptions - i and ii.

i) The position is in a structure that remains unchanged - static and stable,

This can be applied to natural deposits, as in ground layering, that do not change over long periods of time. But less for a hole or ditch. that must remain without cleaning out, altering, or re-digging after construction which is highly unlikely.

Having constructed an open hole or ditch/bank structure for functional, (defensive, rural, or observatory), ceremonial, or ornament use, it is not going to be left with no maintenance, further changes, or development - left undisturbed to collapse and silt up by the community that created it.

ii) The contents of the structure are left in their original position.

The history of most archaeological sites is one of continual disturbances, and it is likely that this goes back to the contents date of deposit, An obvious cause of disturbance is scavenging, an example of which is the digging of a large, deep hole within the Sarsen stone circle in 1620 by George Villiers, 1st Duke of Buckingham, who was looking for treasure ! Source - George Villiers Fifth paragraph down. This destroyed any hope of finding central markers.

Neither assumptions can be applied to the Y&Z holes.

Deductions -

Y&Z holes post-dating the Sarsen stone structure -

Points 1 and 2 have been shown to be inaccurate, with point 3 being inconclusive, and resting on a personal opinion.

Y&Z holes pre-dating the Sarsen stone structure -

Point 4 offers firm evidence as per the sight lines that date the Y&Z holes before the stone structures. This is supported by point 5. Point 6 gives an indication as per consideration (a) above.

It is possible that the initial build was that of the Eastern arc, with the arc extended anti-clockwise at a later date from the Eastern arc with an off-set centre. A later Sarsen stone structure surrounded by a double circular arrangement of white holes and an outer white ditch ring would have looked very effective, especially in moonlight !

Dating is a tricky business, as demonstrated when a Roman coin found beneath a falling stone led to the belief that Romans built Stonehenge.

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