Hello all: Having been away for the week of (US) Labor Day, I return to a mailbox full of interesting items. Not being a sundial constructor, but having had interest in the math and such topics may I address this question?
I suggest the phrase Zonal Apparent Time. My reasoning: The sun (ie, true sun; the thing up there; hence time on a sundial) identifies Local Apparent Time (referred to by some as Local True Time, since it is the true sun.) Correcting for longitude provides the Apparent Time at the Meridian of the time zone. That is what a sundial would read at that place. The EOT "changes" the Apparent Time defined by the True Sun to the Mean Time of the (fictitious ) mean sun. It is the mean sun which provides for 24 hours per day . The true sun is "off" this arbitrary standard by the amount of the EOT. Eg: I am at 118º W. My zone is defined as 8 hours slow on GMT hence by the Meridian at 120º W If my sundial reads noon, then it is 1200 hrs LAT; when it is noon at 120º W's dial , my dial reads 1152 hrs. Notice that NO clock will read these times unless the EOT is 0 for that day. Clocks refer to the fictitious Mean Sun. Hope that helps. I am using 19th Century simple definitions of course without reference to Ephemeris Time, UT, UT(0), UT(1) or Atomic Time. DAVE 33º 39' N 118º 05' W ..........by my own sights and subject to change :) John Carmichael wrote: > Hello all: > > I've got a little simple question that I'm not quite sure how to answer. > > What would be the correct definition of the type of time shown by a sundial > which is longitudinally corrected, but NOT corrected for The Equation Of Time? > > Thanks so much, > > John Carmichael > http://www.azstarnet.com/~pappas > > p.s. Tony Moss said that he had a problem logging onto my website. Would any > of you living in Great Britain mind checking to see if you too are having > trouble?
