SaberScorpX wrote:

In a book on prehistoric astronomy, the author describes the use of a gnomon

to determine E-W from the sun.

...my questions a
1. how accurate is this method ?
2. who was the first to discover ?
3. when was it discovered ?


I don't know about 'prehistoric' astronomy, but ancient astronomy records
generally credit Anaximander with the first use of the gnomon (shadow-chaser)
in the 5th century B.C.
It was first used only to predict midday, and the coming of solstices
and equinoxes.
Later, a 'dial' was placed below the gnomon and divided into
'hour' lines from sunrise to sunset.
http://www.perseus.tufts.edu/GreekSc...ris/TIME2.html

SSX

The book in question is "Prehistoric Astronomy in the Southwest" by J. Mckim Malville
and Claudia Putnam.


--
Wayne T. Watson (Watson Adventures, Prop., Nevada City, CA)
(121.015 Deg. W, 39.262 Deg. N) GMT-8 hr std. time)
Obz Site: 39° 15' 7" N, 121° 2' 32" W
(Formerly Homo habilis, erectus, heidelbergensis and now sapiens)

"The truth is a precious commodity. That's why it is sparsely used."
-- Mark Twain

Web Page: home.earthlink.net/~mtnviews