Dear Frans,
thanks again for your answer and the link provided. In the meantime I had
time to look up the link and the information behind it. By the way, the
link did also lead me to some phantastic informations.
Well, I must admitt that I do not understand the theory behind the Trifilar
Sundial. I tried therefore to find more about it.
F. de Vries writes in "Contents of Bulletin 97, May 2008": ...The appendix
give practical construction calculations.....". Would you have any idea
where that may be found? He also must have investigated the dial quite a
bit because he indicates figures of the inclination and declination of the
dial in the picture (?).
Bifilar dials are interesting, but this trifilar dial is even more so. I
would really learn more about the theory behind it. So, be so kind and try
to help.
Thanks a lot and kind regards
Siegfried
Siegfried Netzband
Hebelstr. 12
75233 Tiefenbronn
Tel: 07234 2802
Fax: 07234 942909
Mob: 0151 53083636 / 0160 1531634
E-Post: siegfried.netzb...@epost.de
Skype: siegfried75233<http://www.ferienhaus-frieseneck.de>
-----Original-Nachricht-----
Betreff: Re: Fake "trifilar" Sun Dial?
Datum: 2020-09-03T14:49:11+0200
Von: "Maes, F.W." <f.w.m...@rug.nl>
An: "siegfried.netzb...@t-online.de" <siegfried.netzb...@t-online.de>
Dear Siegfried,
Bernard Rouxel of France designed this original sundial.
It got him second prize in the Italian "Le ombre del Tempo” contest of
2008.
It was discussed by the late Fer de Vries in one of his online articles.
That website does not exist anymore, but you can find his articles in
"Fer's legacy":
- Go to<http://www.zonnewijzerkring.nl>
- Click the English flag
- Click "Downloads"
- At the bottom of the page, download the zip-file and unzip
- Open "FersLegacy.html"
The article is in the section "Article of the Month", November 2009.
Enjoy!
Best regards,
Frans Maes
On Thu, Sep 3, 2020 at 10:34 AM Siegfried Netzband <
siegfried.netzb...@t-online.de <mailto:siegfried.netzb...@t-online.de> >
wrote:
Dear sundialists,
found the attached picture in an old archive and do not have any details
about it.
The dial shown seems to be somethig like a "bifilar sundial with three
straight wires". The wires obviously do not touch one another. The
picture was taken at the moment when all wire shadows cross in one point
on the dial face suggesting that the sundial shows the time at that
moment (and any other?). There is no dial face visible. What kind of sun
dial is that - what could be the idea behind it and it´s purpose?
Is there anyboddy out threre who could answer the following questions and
can help me to solve my problem, i.e. clarify that sun dial:
- Has any one seen that picture before? If so, do you have any details
about it? Please let me know.
- The originator of that sun dial must have had some very special ideas
when constructing that sun dial. To the best of my knowledge a picture
like that where the shadows of three wires which do not touch one
another, mounted at different heights and angles across the face of the
dial, cross in one point on the face of the dial, can only be taken at at
most 2 times a year, each time at exactly the same solar time. Am I right
or does there realy exist something like a "trifilar sundial" as shown in
the picture idicating time over the year?
- Taking the sun dial shown to a singular, simplistic extreme: At
whatever angles or hights multiple wires might run across a dial and
touch each other at their crrossing point, the dial would simply work and
could be calculated taking the crossing / touching point as the tip of
the gnomon, the node of the dial. Correct?
- Does any one know wether H. Michnik, the inventor of the bifilar sun
dial and its theory in 1923, has made any mathematical statement about
"multifilar sundails"?
Thank you for your help and
Kind Regards
Siegfried
Siegfried Netzband
Hebelstr. 12
75233 Tiefenbronn
Tel: 07234 2802
Fax: 07234 942909
Mob: 0151 53083636 / 0160 1531634
E-Post: siegfried.netzb...@epost.de <mailto:siegfried.netzb...@epost.de>
Skype: siegfried75233<http://www.ferienhaus-frieseneck.de>
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