Hi Douglas & all, It doesn't obey the initial conditions, but maybe a play-object is allowed in a playground. How about a horizontal bar, on which children may turn somersaults etc.? It can double as a sundial: let the bar just tilt 2 deg (3 cm at 1.70 m length), North end upward. Hour lines are almost parallel, as this is almost a polar dial.
Regards, Frans Maes ----- Original Message ----- From: "Douglas Hunt" <[EMAIL PROTECTED]> To: <sundial@rrz.uni-koeln.de> Sent: 18 January, 2004 7:54 PM Subject: A 'gnomon-less' sundial for locations near the Equator ? > > Can any of our Mailing-List experts suggest some horizontal sundial design > suitable for locations almost on the Equator, (actually 2 Degrees North) ? > > We have been contacted by a school in Singapore, who would like to install > a large playground sundial - BUT ideally having nothing above ground-level > to cause any 'accidents', or increase the cost/complexity of their layout. > They want to avoid a 'gnomon' obstructing vehicles in the playground area. > > They had initially thought of using a traditional "analemmatic", but those > are not really suited to locations within the 'tropics' (because the Hour- > markers will interfere with the central Date-scale). We recommended using > a 'door-frame polar' design, as being the most popular for schools near to > the Equator (i.e., two upright supports with a near-horizontal North/South > cross-piece, the shadow of which tells time on Hour-lines painted on their > playground) - but they prefer an entire layout on the ground, if possible. > > I will be very grateful for any suggestions, as to whether there is a type > of sundial which could be installed at a near-Equator location - and which > does not need a 'gnomon' (apart from maybe a person!), above ground-level. > > Douglas Hunt. > > -- > > "MODERN SUNCLOCKS" - 'Human Sundials', using YOUR OWN SHADOW to tell time. > > Looking for a useful, decorative, yet UNIQUE feature ? - you've found it ! > For further details and photographs, see our Website at: www.sunclocks.com > > Mail Address: 1 Love Street, Kilwinning, Ayrshire, Scotland, KA13 7LQ, UK. > Tel & Fax (UK): 01294 552250. International Tel & Fax: + 44 1294 552250. > E-mails to: [EMAIL PROTECTED] OR [EMAIL PROTECTED] > - > -