A Sundial For All

Below are images of a sundial built by Keller Engineers, Inc. in Hollidaysburg, Pennsylvania for a local park. Paul Kirby, the project manager, contacted me during the summer of 2000 to let me know his firm had built this sundial as a public service project for their town. The construction was based on the information in the YPOP sundial lesson pages.

Upon completion of the sundial Paul contacted me to discuss why the sundial time did not agree with "clock" time. I had a nice discussion with him about corrections for the equation of time and for local longitude. Keller Engineering wrote up an explanation of these effects and erected a plaque at the site to help visitors compare the sundial's time with their watches.

If I am ever near Hollidaysburg I hope to visit this terrific sundial someday.

-- Michelle Larson

return to sundial lesson