About Pendulums

A pendulum is one of the simplest devices imaginable. In its most basic form it is nothing more than a weight suspended on a piece of twine or sinew.


Since the pendulum has another function, as a plumb line, it may well be one of the first devices used by humanity. If allowed to hang, the weight of a pendulum will pull its string into a perfectly vertical position. Certainly the Megalithic people could never have constructed any of the major sites to be found all over Britain, Ireland and Brittany without the use of this device.


It is therefore reasonable to suggest that if they possessed a plumb line, they also possessed a pendulum .

Although the device had been around for a long time it was the sixteenth-century genius Galileo who seem s to have been the first person to look seriously at the attributes of pendulums (or at least the first of whom we have a record.)


He is reported to have been bored in Church one day when his attention was caught by a large incense burner suspended from above by a chain or a rope, gently swinging back and forth and forming a natural pendulum. Galileo realized that the swings of the pendulum were equal in terms of time and he counted them against the beat of his own pulse.

Only two factors are of importance in the case of a simple pendulum. These are the length of the string and the gravitation of the Earth, which constantly exerts a pressure that will eventually bring the pendulum back to a vertical and resting position.


The height of the swing of a pendulum is, to all intents and purposes, irrelevant because its time period from one extremity to the other will always be the same. In other words if the pendulum is excited more vigorously it will swing higher but its time period will remain the same.

It was a recognition of this constant nature of a pendulum that made it useful in the creation of clocks. In modern timepieces the pendulum has been superseded, but for many centuries it ensured the smooth running of clocks all over the world. It can still be found in quality clocks.


Clock pendulum s were eventually fitted with devices to prevent them from swinging too high, and others to regulate the nature of their arc of swing, but they are still, essentially, only animated plum b lines.


The Megalithic Yard

The Megalithic Yard was discovered by Alexander Thom as part of the composition of Megalithic sites from the northernmost part of Scotland, right down to Brittany in the South.


The main problem with its use, and the reason archaeologists still doubt its veracity, lies in the fact that it remained absolutely accurate across thousands of square miles and many centuries. This would appear to be impossible in the case of a culture that was, at least in its early stages, devoid of metals to make a reliable 'standard' against which others could be set.

Alexander Thom himself could think of no reliable way of passing on the Megalithic Yard without some variation being inevitable across time.

We eventually reasoned that it would be possible to turn 'time' into 'distance' by way of the turning Earth. The speed of the Earth on its axis is as accurate a yard stick for the passing of time as anyone could reasonably require for most purposes. Of course we can't see the Earth turning but we can see its effects.


The Sun, Moon and stars appear to rise from below the horizon in the east, to pass over our heads and then set in the west. In fact, although the Moon and planets do have independent movement, the Sun and the stars are not really moving at all (actually they are moving slightly but we need not concern ourselves with this for our present purposes).

The apparent motion of the stars is caused by the Earth turning on its axis and it is this fact that offers us an accurate clock which, with a little ingenuity, we can turn into a replicable linear unit of measurement. In the case of the Megalithic Yard we eventually discovered that the pendulum upon which it is based was set not by viewing any star but the planet Venus.


Venus is, like the Earth, orbiting the Sun. As a result, when seen from the Earth, it has a complex series of movements against the backdrop of the stars. Sometimes Venus rises before the Sun, at which times it is called a morning star, and at other times it rises after the Sun and is then known as an evening star. This is purely a line-of-sight situation, caused by the fact that both Venus and the Earth are orbiting the Sun.


When Venus crosses the face of the Sun to become an evening star, it is moving 'against' the direction followed by the backdrop of stars. It is within this observable fact that setting the Megalithic pendulum becomes possible.

In order to create the Megalithic Yard one has to follow the simple rules below:

Venus must be observable as an evening star, setting after the Sun and during that period at which it is moving at its fastest counter to the backdrop of stars.

The sky is divided into 366 parts.


This can be achieved by trial and error, as explained in Uriel's Machine 44 and also in Civilization One 45 but is also achievable through a neat little mathematical trick demonstrated below.

  1. Stand in an unobstructed position on a wide open piece of ground with a good view of the western horizon.

  2. Place a stick in the ground (stick A) and stand facing west with one of your heels touching the stick.

  3. Now take 233 steps, heel to toe, towards the west. Upon completing the 233 steps, place a second stick in the ground (stick B) in front of your toe.

  4. Turn to the north and place your heel against stick B. Now take four heel-to-toe steps to the north and then place a third stick (stick C) in the ground in front of your toe.

  5. The distance between sticks B and C, when viewed from A will now be 1/366th of the horizon.

It is now necessary to make a braced wooden frame of the type shown in figures 14 and 15, which is as wide as the gap between B and C. This must be set on poles in such a way that it gains significant height and can be altered in its angle.

The purpose of this exercise is so that the angle of the braced frame can be identical to that of the planet Venus as it falls towards its setting position.

Standing at A it is now necessary to observe Venus passing through the gap in the braced frame whilst swinging a pendulum and noting the number of swings achieved as Venus passes through the gap.


A pendulum that swings 366 times during this occurrence must be 1/2 of a Megalithic Yard in length (41.48cm).


The cord of this length represents the full Megalithic Yard of 82.966cm in length.


Figure 14




In this way the Megalithic Yard can be reproduced on any site where observation of Venus, when at the right part of its cycle, can be achieved. For the use of the braced frame we are grateful to the considerations of Professor Archie Roy, Emeritus Professor of Astronomy at Glasgow University.

Although pendulums differ slightly with latitude and altitude, because gravity also alters slightly, we have shown that the Megalithic Yard achieved using this method will remain within the tolerances discovered by Alexander Thom from Orkney in the north to Brittany in the south, in other words across the whole area containing monuments surveyed by Alexander Thom.

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