Sundials - World's Oldest Clocks

North American Sundial Society


Sundial: 491
State/Province:  District of Columbia Country:  USA
Dial Type:  Gnomonic or Projection Dial Condition:  Good
  Latitude and Longitude:   
  • Inside Building 207 at the Naval Research Laboratory. Requires an escort from the visitor center.
  • With a bit of whimsy at the end of each day for over two years, Dr. James Griffith marked the position of a ray of sunlight on a wall that entered from a west window overlooking the Potomac river. The result is an analemma, tracing the sun's position at 4:10 pm E.S.T. throughout the seasons. Dr. Griffith was a chemist, but as written on a plaque next to the analemma, "Exactly what this has to do with chemistry per se is not perfectly clear, but Viva Principia Scientifica!" Photos may be seen on Walt Sanford's web site.
General Information:
  • Owner: Naval Research Laboratory
  • Designer: Dr. James Griffith
  • Builder:
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