Date: Thu, 29 Jan 1998
From: Simon Cassidy <scassidy@EARTHLINK.NET>
Subject: Re: Intel and Stonehenge

Tim Ames wrote:

> This might be of interest to some of you. I just logged onto Intel's
> website to get some technical info. The opening page on their
> site has a link to a "Virtual Stonehenge" exposition.

Simon notes:

This "virtual" Stonehenge has been around for more than a year on the web. It is a joint project of Intel (+ Viscape) and English Heritage. The imprimatur of English Heritage (official custodians of the real Stonehenge) lends an aura of authenticity and archaeological expertise to this virtual-reality exhibit. Thus it is regretable that there was a major error in the implementation of an otherwise meticulously detailed rendition of the monument and its surroundings (the current landscape around Stonehenge is faithfully modeled in 3-D at distances of a kilometer or more). This error concerns the rendition of the Stonehenge ruin as it exists today and is not just a question of reconstructing its past appearance. The error concerns the size of Sarsen circle stone #11 (the southernmost erect stone) which a visit to the real site reveals as being only about half the height of its fellow Sarsen circle uprights. Every time I have viewed the English Heritage digital model this stone (#11) has been portrayed as full height. This might be excusable for a speculative reconstruction of this stone's appearance in past ages (though I have never seen convincing evidence that it was ever taller than its current height), but it is lamentably misleading to distort its real current appearance.

The importance of this detail relates to the two major reconstructions which have been proposed for the central sarsen structure at Stonehenge. Everyone is familiar with the usual version which has a continuous circle of thirty lintel stones supported by thirty full-height upright stones. Fewer people are familiar with the major alternate reconstruction (see the book "Stonehenge and its Earthworks" by Edgar Barclay, 1895, for an early presentation of this alternate picture) which has the southern stone (#11) at half height and thus unable to support lintels across to its neighbours. Barclay and others have thus implied that the total number of lintels was originally two less than the total implied by the dominant assumption.

This difference of opinion concerning the original appearance of the monument was just cosmetic until astronomers such as Sir Fred Hoyle recently began speculating on the significance of the number of sarsen stones and their subsets. It turns out that an original monument with 73 sarsen stones (rather than 75) is incredibly richer in calendrical/astronomical significance. These significances are supported by the historical development of calendrical astronomy in early numerate cultures worldwide (e.g. Babylonian and Mayan) as opposed to the usual purported "astronomy" of Stonehenge which is concerned with geometry and sophisticated modelling of the cycle of the lunar nodes (topics almost unprecedented in the history of practical astronomy until the Late Classical Greeks).