The museum has several sundials that operate well on SUNNY days. Click on one of the pictures below to show the complete set, then click on any picture to enlarge it and read the caption.
There are two portable garden sundials on the front lawn that are not very accurate. One has the typical flat dial and fixed gnomon (shadow caster) on a concrete base. The other with adjustable gnomon for setting local latitude has a brass armillary type of dial where the shadow cast by the arrow shaft moves across the semicircular array of hour markers.
There are two wall sundials that show standard time during the winter and daylight saving time during the summer. These were designed and made for the museum in 2001 and 2003 by Julian Brown of Kingston and are modernized versions of the types of wall sundials used in Europe thousands of years ago. Time is read from the straight edge of the shadow on the dial.
The colourful wall example with the copper gnomon on the front of the building catches the mid-day through afternoon sun. The tip of the shadow moves daily as the shadow gets longer (December 21 to June 21) or shorter (June 21 to December 21). The tip falls on one of the colour zones that refer to the seasons - green for summer grass and white for winter snow, red and yellow for both spring flowers and fall leaves.
The wall example facing the driveway around the corner with the pink Plexiglas gnomon catches the morning and mid-day sun. Both wall sundials are two feet square. Note the very different layouts of the dials because of their 90 degrees difference in angle to the sun.
In the summer of 2008 we installed a "human" analemmic sundial on our front lawn. A visitor can stand on the correct month on the centre board set into the lawn and use his/her shadow falling across an array of numbered round patio stones to estimate current time to within about ten minutes. The pink round patio stones are used for daylight saving time and the grey stones for standard time.
Because of our climate, this unusual sundial is buried under snow during the winter, from late November through late March ! (But our wall sundials still work well, on sunny days, in the winter).
Douglas Hunt at www.sunclocks.com in Scotland can provide the correct dimensions for the layout of a human sundial based on your latitude and longitude on the earth. Apparently these designs are very popular with schools, where the centre board and numbers can be set out on the playground.
Check out this interesting sundials web site: http://www.sundials.co.uk/types.htm.
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