I'm grateful for the generous reception you gave to my last contribution to 
this thread.  Here belatedly is another possible solution, less impractical but 
more complex than my last effort.

Imagine a North-South meridian line on flat ground.  On this line place a thin 
flat vertical mirror - essentially a vertical reflective slit - a few feet 
above the ground and pivoted to rotate about a vertical axis through the mirror 
and the meridian.  When the sun shines, a visitor is asked to turn the mirrored 
slit so that the sun's reflection falls along the meridian line.

Straight below the slit, locked to the same vertical axis, is a small 
horizontal analemmatic sundial, a few inches across, placed so that the axis of 
rotation of the assembly coincides with the calendar date-point on the 
analemmatic dial, and the major axis of the analemmatic dial's ellipse is 
parallel to the plane of the mirror.  The direction of the meridian line 
indicates the solar time on the (modified, see below) face of the analemmatic 
dial.

The azimuth of the mirror, measured from the meridian, would be only half the 
azimuth of the sun, so the hour markings on the analemmatic dial would need 
adjusting, e.g. the 1pm mark would be relabelled 2pm (sorry, 10.am).  They 
would run anti-clockwise, and would of course be reversed from north to south.

A groundsman would have to keep the mirror polished, and realign the date-point 
with the axis of rotation perhaps once a week.  He might fix a different dial 
for daylight saving.

Now comes the nifty bit!  Mr Phillips is not forced to accept a North-South 
meridian line.  He could commission a line parallel to his main driveway, for 
aligning the reflection of the sun.  A small fixed North-South marker would 
still indicate the time on the analemmatic dial.  I leave it to the 
heavyweights to recalculate the hourly markings on the dial face.

Alas the gnomon is no longer human, but the device would be interactive, 
instructive and, I daresay, unprecedented.

Apologies for a disgracefully late entry!

John Lynes


-----Original Message-----From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]

Dear Sundial Experts,  
I have recently joined this Mailing List, and hope that any members will be 
able to give me some assistance on the following situation.
Our local Stately Home ("Kentwell Hall", Long Melford, Suffolk) is considering 
installing an Analemmatic sundial, as a new interactive attraction for visitors 
- but we are getting 'conflicting' advice, on whether this 'Human Sundial' will 
work in the way we want it to.  We have been in discussion with "Modern 
Sunclocks" (apparently the acknowledged 'experts' for these features), who have 
told us that its central scale of dates must be aligned North/South - plus that 
hour markers must be correctly positioned on an elliptical ring, and which 
would lie on the Northern side of that scale of dates.
Photographs on their website ( www.sunclocks.com ) confirm this.
However, our 'Director of Operations' (Mr Phillips) absolutelyINSISTS that he 
wants the scale to run exactly parallel with ourmain driveway - on a compass 
bearing which is about 162 degreesfrom North, with the hour points placed on 
its Southern side.He also wants the hour points to form an exact semi-circle, 
andnot be elliptical in shape.  Mr Phillips refuses to accept thathe cannot 
arbitrarily position the Human Sundial feature as hewishes, and says that it 
must be possible to create this so thatit could then align with the existing 
layout of buildings/paths.
Can anyone on this Mailing List tell me whether it is possible toinstall a 
Human Sundial to fit any existing orientations, (withappropriate re-calculation 
of its component parts) - or, if not,just confirm that it must be as "Modern 
Sunclocks" have told me.
I can then show the 'weight of evidence' to Mr Phillips.  Because"Kentwell 
Hall" is a well-known Stately Home (open to the public),we should not want to 
become a 'laughing stock' by installing afeature which does not work - despite 
Mr Phillips assurance that"all types of sundial can be adjusted to work, in any 
location".
Looking forward to all comments (to this List, or sent privately).  Sincerely,  
Alison Shields.

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