Dear Josef Pastor,

Thanks for your e-mail about the project in Recklinghausen. It's very
impressive and especially the large sundial is interesting to the readers of
this sundial list.

However, I want to make a remark to the picture of the sundial of Emperor
August as showed on poster4.

That picture is a copy of a drawing in the book "Die Sonnenuhr des August"
by Edmund Buchner, 1982, page 43.
Buchner describes the idea that in this sundial a "day light triangle" could
have been present and draws 2 curved lines for this triangle.
With this triangle may be read how many hours a certain day will be longer
then the shortest day in winter.
Following Buchner's description however, these 2 curved lines are wrong and
should be 2 straight lines.

In the bulletin of "De Zonnewijzerkring" nr. 84.2, september 1984, I wrote
an article about this triangle and the error Buchner has made in his
drawing.

As a follow up René R.J. Rohr gave a better proof that indeed this triangle
should have straight lines and an article of Rohr ( in German ) was
published in the Dutch bulletin nr. 85.1, february 1985.
Rohr describes that one of the lines is a Babylonian hour line and the
second is an Italian hour line and these lines are straight on a flat
surface.

A drawing with the correct triangle with straight lines may be found in the
booklet "A Sundial for your garden" by Harold E. Brandmaier, 1995, page
2-10.

I write this all because it would be a pity if a wrong drawing of the dial
of Emperor August will be spread all over the world.

Best wishes, Fer.

Fer J. de Vries
[EMAIL PROTECTED]
http://www.iae.nl/users/ferdv/
Eindhoven, Netherlands
lat.  51:30 N      long.  5:30 E

----- Original Message -----
From: <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Thursday, May 17, 2001 9:29 PM
Subject: Giant Sundial


> Dear Dialists,
>
> the &#8222;Volkssternwarte and Planetarium Recklinghausen&#8220; in
Germany
> is going to plan a giant sundial (30m in diameter) on top of the mine dump
> &#8222;Hoheward&#8220; within a park of horizontal astronomy.
> You can get a first impression on the web on the homepage of the city of
> Recklinghausen. There you will find 6 posters of which one is written in
English
> and some pages with description and astronomical data.
> http:/www.recklinghausen.de/sterne/Haldenposter.htm
>
> Enjoy the design studies.
>
> Josef Pastor
> recklinghausen
> [EMAIL PROTECTED]
>
> --
> GMX - Die Kommunikationsplattform im Internet.
> http://www.gmx.net
>


Reply via email to