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Index of Subjects
circular structure with 12 stone
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Dave=0AI always assumed the 360 came first - close to=0Athe days in the yea=
r. Having spent many working days dealing with circles and angle it was luc=
k correctness was not a concern, just imagion if they had decided on 365 de=
grees in a circle.=0AEnjoy the moisture=0APaul =0A=0A=0AOn Monday, August 1=
8, 2014 8:54:38 AM, Dave&Jane Schlosberg <dschlosb-g@ns.sympatico.ca> wrote=
:=0A =0A=0A=0ASince the radius goes almost exactly 6 times around the circ=
umference, =0Aperhaps early builders used that to divide their circles.=0A=
=0A-----Original Message----- =0AFrom: Stephen Shaw=0ASent: Monday, August =
18, 2014 2:25 AM=0ATo: naturens@chebucto.ns.ca=0ASubject: RE: [NatureNS] Ne=
olithic stone rings etd.=0A=0AHi Dave:=A0 You need an astronomer with an in=
terest in history for this, so =0Astand by, hopefully, for input.=0A=0AMean=
while, this astronomical observatory idea originated I think with =0AAlexan=
der Thom, based on his idea of a a common unit of length, the =0Amegalithic=
yard (MY) of 2.72 feet.=A0 This unit supposedly had been used with =0Aprec=
ision to lay out British and French neolithic stone circles.=A0 While this =
=0Aseems not to have been entirely discredited, later critics doubted that =
=0Athere was a unit with this precision in universal use, and that distance=
s =0Acould have been measured adequately instead simply by pacing-out, not =
=0Anecessarily by using a common physical yard-stick.=A0 I can't remember t=
he =0Aconnection, but the MY supposedly was somehow related to an astronomi=
cal =0Acycle, indicating that you must have had active neolithic astronomer=
s to =0Amake the connection.=A0 Perhaps someone else can remember the conn=
ection, or =0Aif I've got this wrong.=0A=0ANot sure about the universal '12=
' ideas.=A0 The main units of time that we and =0Apresumably earlier popula=
tions used were based on 3 quite different =0Aastronomical cycles that are =
unrelated.=A0 Days are/were measured based on =0AEarth's daily rotation on =
its axis, easily counted though not precisely =0Aconstant.=A0 Months depend=
ed on the Moon's rotation about Earth, easily =0Aobserved as recurring phas=
es of the Moon.=A0 Years are/were measured in time =0Aunits based on the Ea=
rth's orbiting around the Sun -- much more difficult to =0Acalibrate accura=
tely, probably accounting for the need to calibrate by =0Abuilding fancy su=
nrise-observing structures, accurate to the day at =0Asolstices.=A0 Very im=
portant for correct crop planting.=A0 Unsurprisingly, =0Aneither of the sma=
ller units in use at present divide exactly into the =0Alargest unit, the y=
ear, or into each other, hence yearly movement of Easter, =0Acalendar day r=
egression and the need for leap years.=A0 Not clear how you =0Awould use a =
megalith with one annually precise alignment axis to tell the =0Atime (for =
instance the day, month) at other times of the year.=0A=0AI've forgotten mo=
st Euclid, but how do you subdivide a circle easily ('a =0Asnap') into 12 s=
ubunits?=A0 I can see how you draw the first line and find its =0Acentre (w=
ill become the centre of the circle) with a rawhide =0Acompass-divider, and=
how you can draw the second diameter at right angles to =0Athis with the s=
ame gear, and then complete the circle.=A0 You are then left =0Awith a circ=
le with 4 equal quadrants, each of which has to be subdivided =0Afinally in=
to 3 segments to make a total of 12, like the hours on a clock. =0AIsn't th=
is the difficult problem of trisecting the angle (bisecting is a =0Asnap wi=
th a simple compass, but I thought trisection was not)?=A0 Please =0Aadvis=
e.=0AOnce you've somehow accomplished the trisection of 4 segments into 12 =
=0Asub-segments with 30=B0 central angles, then 24, 48, 96... segments are =
easy =0A(bisection), as you imply.=A0 But subunits of 60 segments are not p=
art of this =0Aseries, so that remains rawhide-unexplained too.=0ASteve (Hf=
x)=0A________________________________________=0AFrom: naturens-owner@chebuc=
to.ns.ca [naturens-owner@chebucto.ns.ca] on =0Abehalf of David & Alison Web=
ster [dwebster@glinx.com]=0ASent: Sunday, August 17, 2014 7:34 PM=0ATo: Nat=
ureNS@chebucto.ns.ca=0ASubject: [NatureNS] Neolithic stone rings etd.=0A=0A=
Dear All,=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 Aug 17, 20=
14=0A=A0 =A0 The August issue of National Geographic has an article that fe=
atures the=0Astone rings and other old (~5000 yrs.) structures of the Orkne=
y Islands.=0AFrom this article & Wikipedia; the circular Ring of Brodgar; s=
paced for 60=0Astones of which 27 remain and the slightly nearly circular b=
ut elliptic (so=0Athey say) ring of the Stones of Stenness; spaced for 12 m=
egaliths with=0Aperhaps 1 or 2 never erected.=0A=0A=A0 =A0 Is it now so wid=
ely recognized that such structures served as=0Aobservatories (an analog ca=
lendar and crude sundial) that it is too obvious=0Ato mention ? Alignment t=
o the winter solstice at sunset (which would also=0Afit the summer solstice=
at sunrise I think) is mentioned but surely these=0Acould have been used t=
o keep track of time throughout the year.=0A=0A=A0 =A0 Even short stones wo=
uld cast a long shadow at sunrise and sunset and the=0Achanges in direction=
=A0 with time would be consistent from year to year. A=0Acircular structure=
with 12 stones is a snap to lay out if you have enough=0Arawhide and this =
natural and practicable number likely accounts for our 12=0Asigns of the zo=
diac, 12 months of the year and 24 hours in the day. But a=0Aring with 60 m=
arkers is slightly more tricky to lay out, using Neolithic=0Ahardware, then=
say a ring of 48 or 96. The number 60 has the advantage of=0Abeing divisib=
le by 2,3,4,5&6 so the designer of this ring was just a step=0Aaway from a =
360o circle; dividing a circle into 60 or 360 parts is=0Aessentially the sa=
me problem and both have similar advantages if fractions=0Aare difficult to=
deal with.=0A=0AYt, Dave Wwbster, Kentville
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<html><body><div style=3D"color:#000; background-color:#fff; font-family:He=
lveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;fo=
nt-size:14pt"><div><span>Dave</span></div><div style=3D"color: rgb(0, 0, 0)=
; font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Gran=
de, sans-serif; font-size: 18.66px; font-style: normal; background-color: t=
ransparent;"><span>I always assu