One of the favourite beach suburbs of Perth is Cottesloe. As you can see from the first photo, it is just north of Fremantle. This photo was taken from a headland at the southern end of the long sandy strip of the beach. On the headland I noticed a strange-looking structure and headed down a convenient path to see what it was. If I had been tall enough to read the signpost at the start of the path I would have seen that this is the Cottesloe Bicentenary Sundial. It is very different to the small garden sundials you often see. It is actually two sundials, a morning one and an afternoon one. The big limestone ramps are gnomons, which throw their shadow onto the curved brass strips. These strips are engraved with time markers. The curvy markings show the difference needed to correct the time shown by the shadow to Western Australian Standard Time, which is set at Kalgoorlie, 4.3 degrees east of Cottesloe (click on the photo for a larger view). We were there at 3:17 pm and the sundial and Dad's watch agreed on the time. This sundial is similar to the giant 18th century ones at Jaipur in India. The beach? Well, it's not bad, but in my opinion we have much better ones in the eastern states.
Labels: astronomy, beach, Western Australia
# posted by Bart Bear @ 11:51 am
