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Why this book is bogus, 16 Feb. 2013
This review is from: Uriel's Machine: The Ancient Origins of Science (Paperback)
Apart from a very distorted view on archaeological theory and the simplistic perception of how archaeologists proposed how civilisations arose there is a serious flaw in the authors key assertion. This excerpt from an astronomy website puts the whole book into its right category: pseudo science.
source: astunit dot com
This commentary will concentrate on the astronomical assertions used. I am not competent to comment upon the archaeological or the geological assertions.
At the end of the Prologue (p. xx), the authors state: "...ancient sites from northern Scotland to Brittany all exhibited the use of a standard unit of measurement that was accurate to a fraction of a millimetre. (...) we show beyond all reasonable doubt that this prehistoric unit was derived from observational astronomy." They claim that the "machine" that they built using "instructions recorded thousands of years ago" gives this curiously precise value.
Knight and Lomas claim that the pendulum that they produced had a length of 16.32" (41.45cm), i.e. precisely half a megalithic yard. This was truly exciting, and a quick mental calculation suggested that the value they published was realistic. However, having been caught out previously when I accepted something without checking, I decided to check. (Note: The authors have objected to my calculation. See here.)
The period of a pendulum, T, is given by: T = 2π(l/g)0.5 where: l = length of pendulum g = acceleration due to gravity.
Knight and Lomas use a "pulse", which I shall abbreviate as "P", of T/2, so we then have:
P = π(l/g)0.5 or: l = g(P/π)2
T is derived from the (sidereal) revolution of Earth, from the authors' notion of a "megalithic degree", and the "instructions" from the distant past. There are 86164 seconds in a sidereal day.[1] This is divided by 366 to give the number of seconds in a megalithic degree, i.e. 235.42 secs.[2] From the authors' interpretation of the "instructions", the pendulum should give 366 "pulses" per "megalithic degree", i.e. have a pulse of 0.643 sec.
The acceleration due to gravity in the British Isles varies from 9.8116 ms2 at latitude 51° (southern England) to 9.8183 ms2 at 59° (Orkney). (Values derived from IGF)
Hence the length that will give this Orkney is:
l = 9.8183 (0.643/π)2 m = 0.4113 m = 41.13 cm (= 16.19")
This decreases to 0.4110 m in southern England; i.e. the variation in the MY over the British Isles (excluding Shetland) would, according to Uriel's machine, be of the order of 0.3mm  to all intents and purposes, this can be taken as being constant. At the latitude of the Algarve (38°) the length is 0.4105m, i.e. less than 1mm different from the Orkney value.
This is close, but not equal, to the value that Knight and Lomas claim to have attained, which is the precise value of Thom's "half megalithic yard", i.e. 41.45 cm or 16.32". To produce this length, g would need to be 9.8946 ms2, i.e. greater than it is at Earth's poles (9.832 ms2)
Gravitational cognoscenti will have noted that I have not taken the affect of altitude into account. At a mean value of 0.3086 mGal m1 this will not affect the calculations above at their 0.1mm precision.
If, as they assert, the precise value of the megalithic yard ("accurate to a fraction of a millimetre") was attained through physical means, Uriel's Machine does not do it. The frequent replication of the megalithic yard would, if it is as precise as is asserted ("a precise megalithic yard"), give it a mean value slightly (but measurably  i.e. 3.5mm or 0.14") smaller than the value that is cited for it by Thom and by Knight and Lomas. I can only assume that the authors inadvertently measured their pendulum or its period inaccurately.
Also, I find it curious that the authors did not present a calculation in the book to confirm their supposition. The high school physics required should be well within the capability of Lomas, who is said (front matter of book) to have a first class honours degree in electrical engineering.
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Uriel's Machine: The Ancient Origins of Science 0099281821
Christopher Knight
Arrow
Uriel's Machine: The Ancient Origins of Science
Welcome
Why this book is bogus
Apart from a very distorted view on archaeological theory and the simplistic perception of how archaeologists proposed how civilisations arose there is a serious flaw in the authors key assertion. This excerpt from an astronomy website puts the whole book into its right category: pseudo science.
source: astunit dot com
This commentary will concentrate on the astronomical assertions used. I am not competent to comment upon the archaeological or the geological assertions.
At the end of the Prologue (p. xx), the authors state: "...ancient sites from northern Scotland to Brittany all exhibited the use of a standard unit of measurement that was accurate to a fraction of a millimetre. (...) we show beyond all reasonable doubt that this prehistoric unit was derived from observational astronomy." They claim that the "machine" that they built using "instructions recorded thousands of years ago" gives this curiously precise value.
Knight and Lomas claim that the pendulum that they produced had a length of 16.32" (41.45cm), i.e. precisely half a megalithic yard. This was truly exciting, and a quick mental calculation suggested that the value they published was realistic. However, having been caught out previously when I accepted something without checking, I decided to check. (Note: The authors have objected to my calculation. See here.)
The period of a pendulum, T, is given by: T = 2(l/g)0.5 where: l = length of pendulum g = acceleration due to gravity.
Knight and Lomas use a "pulse", which I shall abbreviate as "P", of T/2, so we then have:
P = (l/g)0.5 or: l = g(P/)2
T is derived from the (sidereal) revolution of Earth, from the authors' notion of a "megalithic degree", and the "instructions" from the distant past. There are 86164 seconds in a sidereal day.[1] This is divided by 366 to give the number of seconds in a megalithic degree, i.e. 235.42 secs.[2] From the authors' interpretation of the "instructions", the pendulum should give 366 "pulses" per "megalithic degree", i.e. have a pulse of 0.643 sec.
The acceleration due to gravity in the British Isles varies from 9.8116 ms2 at latitude 51° (southern England) to 9.8183 ms2 at 59° (Orkney). (Values derived from IGF)
Hence the length that will give this Orkney is:
l = 9.8183 (0.643/)2 m = 0.4113 m = 41.13 cm (= 16.19")
This decreases to 0.4110 m in southern England; i.e. the variation in the MY over the British Isles (excluding Shetland) would, according to Uriel's machine, be of the order of 0.3mm  to all intents and purposes, this can be taken as being constant. At the latitude of the Algarve (38°) the length is 0.4105m, i.e. less than 1mm different from the Orkney value.
This is close, but not equal, to the value that Knight and Lomas claim to have attained, which is the precise value of Thom's "half megalithic yard", i.e. 41.45 cm or 16.32". To produce this length, g would need to be 9.8946 ms2, i.e. greater than it is at Earth's poles (9.832 ms2)
Gravitational cognoscenti will have noted that I have not taken the affect of altitude into account. At a mean value of 0.3086 mGal m1 this will not affect the calculations above at their 0.1mm precision.
If, as they assert, the precise value of the megalithic yard ("accurate to a fraction of a millimetre") was attained through physical means, Uriel's Machine does not do it. The frequent replication of the megalithic yard would, if it is as precise as is asserted ("a precise megalithic yard"), give it a mean value slightly (but measurably  i.e. 3.5mm or 0.14") smaller than the value that is cited for it by Thom and by Knight and Lomas. I can only assume that the authors inadvertently measured their pendulum or its period inaccurately.
Also, I find it curious that the authors did not present a calculation in the book to confirm their supposition. The high school physics required should be well within the capability of Lomas, who is said (front matter of book) to have a first class honours degree in electrical engineering.
Caver
16 Feb. 2013
 Overall: 5

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