This family divides into 4 subclasses. The Curve is - in all cases - a representation of the analemma. (see page 'Displaying the Equation of Time'). All, except Spider Dials, require a nodus or a point gnomon. They are the commonest and easiest-to-make equation-corrected sundials. The Equation of Time is usually combined together with the longitude correction.
(see also Noon Marks, below)
From Left to Right : Click to enlarge :​​​​​​​(i) Rafel Soler i Gaya -1988 - Port of Tarragona, Catalonia : (ii) J Girbau - 1989 -Castelifollit de la Roca, Catalonia : (iii) Harriet James : East/West Vertical Declining Dial
These are easier to read than full analemmas, but either required the biannual change of the dial plate, as in the first two examples or two separate dials
From Left to Right : Click to enlarge :  (i) Victorian Traveller's Sundial (ii - iii) Christopher St. J. H. Daniel - 1977 - Dolphin Dial, Royal Observatory, London (iv) Albin Hoffmann - 2007 - - Bütgenbach-Belgium (v) Sir Mark-Lennox Boyd & Ben Jones - 2004 - Rosemoor Garden, Devon, UK (vi) ? Guiseppe Mara ? & ? Renaudi ? - 1997 -Chiusa di Pesio Nr Turin (vii) W.F. Ng - 1986 - Magdalene College, Cambridge (viii & ix) Sir Mark Lennon-Boyd & Fergus Wessel - 2013 - Obelisque Dial, Egyptian Garden, Buscot Park, Oxfordshire
These a subclass of the Full Analemma Class - but were often used to set church clocks.
From Left to Right : Click to enlarge : (i) Urbain Adam -  1866 - Cathedral of  St. Martin, Colmar, France (ii) Christopher Daniel - 1995 - Radcliffe Observatory, Oxford, UK. (iii) Dr Alan Mills - 2007 - Eye of Time, Leicester University, UK. (iv & v) Dr Frank King - 2004 - London Stock Exchange, UK (vi) Alastair Hunter - - 2011 - Noon Mark (vii) Vic McGrath - after 2001 - Smooth Sailing, Reconciliation Place, Canberra, Australia
These require a lot more calculation to delineate, but are used with a standard gnomon. A nice feature of the spider dial is its ability to indicate sunrise and sunset times 
From Left to Right : Click to enlarge : (i) Mac Oglesby - 2002 - Vertical Declining "Rainbow"  Spider Dial, Brattlesbury, Vermont, USA (ii) Mac Oglesby - Monofilar Standard Time Polar Dial (iii) Rick Twardy - 2001 - Parkes Observatory, Dubbo, New South Wales (iv - v) Author's bronze Highfield House dial - 2016 - before being exposed to the atmosphere and two years later (vi) How to read a Spider dial.
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