Sundial of Human Involvement
The Kingston SE Sundial is located on a small island in Maria Creek adjacent to the Apex Park. Correctly known as an Analemmatic Sundial the work consists of a central analemma and a number of hour pieces in a half circle formation.
The Sundial was designed by Dr Margaret Folkard and Mr John Ward of Sundials Australia in Adelaide. Well known fine art Sculptor Mr Silvio Apponyi produced the pieces which make up the Sundial and the numerous animal, fish and wave works which are featured on and around the Sundial pieces.
The Analemmatic Sundial
An Analemmatic Sundial is a horizontal Sundial which does not have hour lines marked on it. Instead of hour lines, it has a series of fixed hour points which are located in a half circle
pattern around the analemma. A person standing on the analemma will cast a shadow which will pass through the hours markers. This type of Sundial records time with respect to the azimuth of the sun. The azimuth is the angular distance on the horizon plane between the truce north-south line and the foot of the perpendicular from the sun to the horizon.
A bronze plaque is located at the left of the Sundial which
provides simple easy-to-follow instructions.
During the day the sun appears to move across the sky, causing changes in both the length and position of the shadow cast by any soild object. The height of the sun above the horizon also varies with the seasons which causes further changes in the position of the shadow.
For more than 5000 years people have used the movement of shadows produced by the apparent movement of the sun for the reckoning of time and for the determination of important days (such as when to plant crops for the following season). Any device which uses either the length of the shadow or its angular position to divide the period between sunrise and
sunset into units of time is known as a sundial.
We are all familiar with the convential horizontal sundials which have beautified gardens for many centuries, and are perhaps also aware of sundial which can be attached to the walls of buildings. These vertical sundials can be placed on walls facing in a variety of directions, and are especially popular in Europe where some towns and villages have become famous because of their wall sundials.
There are many different sundial types and, if designed and used correctly, all types will tell the time quite accurately. The hour markings on almost all accurate sundials depends on the latitude where they are placed, but not all types are suitable for use everywhere in the world (for example, horizontal sundials used near the Equator, or vertical sundials used near the Poles, are not always accurate).
Another example of a Sundial similar to this is located at Mount Annan Botanic Garden (The native plant garden of the Royal Botanic Gardens, Sydney).
Time Keeping Accuracy of Sundials
Any sundial which is properly designed for its location will
readily tell the time accurately to a minute or two for the next few centuries. However, before the Sundial will show the same time as that indicated on your watch, it is necessary to consider two corrections to the shadow reading.
The first correction occurs because the orbit of the Earth around the sun is elliptical, and the Earth slows down when we are
furthest away from the sun and speeds up when we are nearest it. This correction is called the equation of time.
The second correction occurs because of the difference in time between the Sundial's location and the local time zone longitude, in this case Central Standard Time (CST). A further adjustment is required during the months of Central Summer Time (Daylight Saving).
This Sundial incorporates the effects of longitude into the position of the granite used as hour pieces, while the equation of time
corrections are built into the central analemma. Correct use of this Sundial will ensure accuracy with your watch.
These two corrections are often combined. Here they are
displayed graphically on a conventional horizontal Sundial which is located to the right of the analemma.
Other Analemmatic Sundials
This type of Sundial is rare world wide. Other examples are at:
Mount Annan Botanic Garden (Sydney)
Cathedral of Bron near Bourg-en-Bresse (SE of Paris)
Great Exhibition Hall in Liverpool (England)
Reinauen Central Park near Bonn (West Germany)
Park near Palace of the Popes (Avignon, France)
University of Arizona (Tueson, USA)
University of North Carolina (Charlotte, USA)
Associated Art Works
In addition to the Sundial several larger pieces of art have been produced by sculptor Silvio Apponyi. The
largest piece features an Elephant Seal and Cub. Other pieces include a Boar Fish, Japanese Crab, two wave rocks and various rock etchings. A Mulloway is located in Lions Park as an acknowledgement by the artist of the Annual Lions Surf Fishing Competition and the
contribution by the Lions Club to the community
generally. A Sleepy Lizard is located at the front of the District Hall in Agnes Street.
Type of Rock
Known locally as "granite" the material used is found at various outcrops which straddle the Princes Highway about 18km north of Kingston and on the beach about 2km north-west of this location.
The rock is of Ordovician geological age (about 450
million years old) and was formed when molten rock
material or magma was pushed upwards into overlying older rocks. Various minerals were formed as the magma solidified and the inter-locking crystals give the "granite" its characteristic texture. The main minerals are quartz, felspar and biotite. The hardness of the quartz and
feldspar minerals make the rock extremely durable.
Geologically the "granite is referred to as granodiorite or adamellite.