IT sundial plaque

A plaque on the north side of the gnomon:

  • is always in the shade
  • is backlit, which makes it more difficult to photograph and may explain why we never found a closeup photo of the original plaque
  • on a sunny day, the sun hits you in the eyes as you face south and try to read the plaque
  • standing in this location to read the plaque, you are blocking other people who are trying to read sundial time in the middle of the day
  • if the plaque needed replacement, or were vandalized, on the 110 year old concrete gnomon, the gnomon could be damaged and the sundial accuracy ruined. This would be very difficult or impossible to repair. The gnomon needs to be precisely aligned in all three dimensions. Concrete benches in Sundial Park and along the border of Ingleside Terraces at Ashton Avenue are missing or broken and have needed replacement or repair
  • the multiple abbreviations needed in the narrow 8"x30" plaque on the gnomon are out of place in a formal plaque
  • the original plaque has been missing probably for 90 years. Its content is unknown and we cannot reproduce that plaque
  • originally, there was a pool of water in the center of the dial. This may have led to reading the sundial from the north, similar to reading an analog watch upside down, and may explain why the plaque was placed on the north side of the gnomon. As the pool has not been present for over 90 years, there was no longer any reason for placing the plaque on the north side of the gnomon
  • the phrase on the plaque "use left shadow edge for AM", which was paraphrased from my 2021 EOT chart, is somewhat confusing. If you are facing south to read the plaque, the left edge may refer to the east side of the shadow. Actually, it applies to someone standing to the south of the dial facing north, and the phrase in the EOT chart "Use the left side of the shadow of the gnomon before solar noon" refers to the west side of the shadow
  • sundial plaques in the northern hemisphere are placed south of the gnomon, so that as you walk towards the dial to read it like a clock, you first reach the plaque
  • this is apparently the only sundial in the world with a plaque on the north side of the gnomon in the northern hemisphere (or the south side of the gnomon in the southern hemisphere)
  • cf. Sundial slides

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