|
The deviation found by Willi shows that this kind
of sundials is not so acceptable as one it would be waited. Still more if the
stile is upright on the wall.
I simply write this opinion of mine about this kind
of sundial or 'pseudo dial' just for personal experience.
As builder and as restorer of sundials, I
often listen people tell me: «I don't know why it don't work! When they
have built the dial it correctly worked, then slowly has
stopped showing correctly the hours». In some case the deviation is really
great, as in my native village that is far from the main meridian.
Someone has blamed even the pigeons that,
according to him, they had moved the iron stylus with their weight.
Of course we know that the birds are not guilty.
Nicola wrote about late 19th and early 20th centuries in the little villages in
the country side, but here many modern peinters still continue to made sundials
in this way, I saw many sundials that doesn't have any idea of the declination
of the wall or latitude angle.
Of course, I know that my grandfather, knew the
time enough correctly looking the sun on the silouette of the mountain around
him: when the sun was in a certain position over a certain pick or tree he knew
that it was time to take the cows back home. Also in the middle age for farmers
the exact time was an unknown concept, But we are talking about a modern
sundial.
I don't know...
Mario
----- Original Message -----
Sent: Tuesday, July 04, 2006 1:08
PM
Subject: Re: Is this a sundial...
continued
To have an idea of the deviation between the time on a
'pseudo-sundial' and a right sundial, this example
for a 'pseudo-sundial' directed to the south and situated in
Roma:
if it is adjusted to real suntime on june 21 (solstitium) it
will gain at march 21 and september 23 (equinox)
- when it indicates 1 o'clock or 11 o'clock: 17 minutes
- when it indicates 2 o'clock or 10 o'clock: 33 minutes
- when it indicates 3 o'clock or 9 o'clock: 49 minutes
- when it indicates 4 o'clock or 8 o'clock: 63 minutes
Willy LEENDERS
Hasselt Flanders
(Belgium)
Yes, the radiating hour lines from the footpoint of
vertical gnomon was the only simple method of the country people out of the
great cityes. Here in Italy this sundials or "pseudo-sundials" are not rare
on the houses of peasants. I think also in a great and modern society, if
someone want a simple sundial without calculations, can track the hour lines
on the wall with a vertical gnomon and seeing the way of the sun in the sky.
It isn't a right way to do a sundial! But very much people used it.
Ciao, Nicola
---------- Initial Header -----------
Date
: Mon, 3 Jul 2006 09:20:15 -0400
Subject : RE: Is this a sundial... continued
Fer and Nicola,
As we know, radiating hourlines are also found on
ancient English "scratch
dials", but as Fer says one would not expect to
find them on a modern dial.
See the dial "embedded in the wall of Saint
Gregory's church, Kirkdale,
North Yorkshire" below:
Bob
-----Original Message-----
Sent: Monday, July 03, 2006 3:40 AM
Cc: bobt; sundial
Subject: Re: Is this a sundial...
continued
Nicola,
Thanks for your addition.
Your notes bring sense to a dial with lines
radiating from
the footpoint of a perpendicular gnomon and
they still exist in Italy.
On the other hand I didn't expect this in a
more modern
society as New York.
Best, Fer.
Fer J. de Vries
De Zonnewijzerkring
Eindhoven, Netherlands
lat.
51:30 N
long. 5:30 E
----- Original Message -----
Sent: Monday, July 03, 2006 9:29 AM
Subject: Re: Is this a sundial...
continued
Dear Bob and Fer,
I have seen in Italy several sundials with
the hour lines
radiated from
footpoint of the vertical gnomon. This are
simple sundials
made from
simple people without gnomonic calculation,
but only with the sun
observation. The precisione is not high, but
good for
living in the little
country of XVIII-XIXth century. I have seen
several
sundials in this mode
on house and church in Italy. Also the
italian diallists
point out this
dials like "pseudo-sundials", and not more
time ago this was a long
diatribe on the italian mailing list on this
subject. But
this simple
sundials are not very rare in Italy and its
are the
testimoniance of
measuring time of our simple people in the
country.
Thanks to all and sorry for my bad
english
---------- Initial Header -----------
To
: "Robert
Terwilliger"
Cc
:
Date
: Sat, 1 Jul 2006 20:09:51 +0200
Subject : Re: Is this a sundial...
continued
Bob, Nicola,
I also saw the "hourlines" on the sunny photograph
of
this dial but they
didn't give sense to me.
They radiate from the footpoint of the
perpendicular
gnomon on the wall,
I guess, and to my opinion they are not
(usual) hourlines.
I don't know the text by Nicola and ask to
place that text
on the sundial
list so we all can learn Nicola's
thoughts.
Best, Fer.
Fer J. de Vries
De Zonnewijzerkring
Eindhoven, Netherlands
lat. 51:30 N long. 5:30 E
----- Original Message -----
From: Robert Terwilliger
To: 'Sundial Mailing List'
Sent: Saturday, July 01, 2006 6:17 PM
Subject: Is this a sundial... continued
Nicola and all,
Nicola, I did not notice the hourlines until you
pointed
them out.
Thank you, this dial is beginning to make
more sense.
I have put another page online with an edited version
of
Nicola's
graphic with a statement and link about the
dial's concept.
Bob
--------------------------------------------------------------
----------------
---------------------------------------------------
---------------------------------------------------
---------------------------------------------------
https://lists.uni-koeln.de/mailman/listinfo/sundial
|
