You are right, I had my beginnings and endings of Sandringham time mixed up. Thanks!
And you are also right, Sundials DO have time problems. They begin with the fact that they are built by people and the smaller they are, by definition, the less precise they can be. The one in Jaipur (I believe) is marked down to 2 second intervals but it still has to deal with the EOT and the changes in the way we move around the sun. the good part about Sundials and the way they read time is they average out over the course of a year. I'll take a look at the Seize the Daylight site. Sounds interesting. I can see the reasoning behind changing for computers, orbital mechanics and interplanetary and, hopefully, interstellar flight. But, for daily use, I think, as you said, there are more important things than knowing to the nanosecond the exact time. Thanks for the site. Karon Adams Accredited Jewelry Professional (GIA) You can send a free Rosary to a soldier! www.facebook.com/MilitaryRosary www.YellowRibbonRosaries.com > -----Original Message----- > From: Tony Finch [mailto:[email protected]] On Behalf Of Tony Finch > Sent: Monday, August 15, 2011 2:23 PM > To: karon > Cc: 'Bill O'Neill'; [email protected] > Subject: the nature of time, was RE: UTC Conference > > Bill O'Neill <[email protected]> wrote: > > > > Sundials however will never have time problems because they indicate the > > position of the earth and sun. As such they do not measure time. A clock > > draws a conclusion but a clock attempts to follow what is displayed by the > > sundial. The sundial follows the earth and sun. Sundials measure position, > > not time. > > Yes sundials indicate the rotation of the Earth relative to the Sun, but > no they DO have time problems because time is not simply determined by > Earth rotation any more - it is adjusted by the equation of time and > standard time and daylight saving time. And at the fundamental > metrological level time is now determined by quantum physics; our clocks > keep physicists' time and we reset them periodically to roughly match > Earth's rotational position. > > karon <[email protected]> wrote: > > > > Does anyone really argue that time IS what a clock says rather > > than a clock being a measure OF time? > > Depends what kind of time you are talking about :-) Civil time is defined > by the procedures we use to set our clocks - it's a cultural phenomenon, > not a pysical one. The civil time broadcasts are derived from our best > measurements of interval time, but the way they are derived is governesd > by a large amount of arbitrariness and politics. > > > In England, King George V, I believe, attempted to correct for > > longitudinal shift to reflect real time by establishing what was known > > as Sandringham Time. The clocks at Sandringham Estate were all 30 > > minutes ahead of the official time for the time zone as the King wished > > to have his clocks reflect the actual time by the sun. > > No, it was Edward VII who established it, and confusion over the time of > George V's death led to its abolition. It was an early form of daylight > saving, and has nothing to do with solar time. Sandringham is only half a > degree East of the meridian, which only requires a two minute correction. > > http://en.wikipedia.org/wiki/Sandringham_time > > > Right now, I am just trying to understand the goals of people with the idea > > of decoupling (was that the term?) standard time from local time or solar > > time for daily use. I just don't understand the reasoning behind it. > > It's mostly for convenience, because other things are more important than > precisely synchronizing our clocks to the angle between our position and > the sun. I suggest reading "Sieze the Daylight" by David Prerau for a > grand historical tour of the arguments. http://www.seizethedaylight.com/ > > Tony. > -- > f.anthony.n.finch <[email protected]> http://dotat.at/ > Fair Isle, Faeroes: Southwest 4 or 5 backing south or southeast 3 or 4. Slight > or moderate. Showers. Moderate or good. --------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial
