> Dear Fer, > > it is not always easy to interpret this argument in the old manuscripts. The > old monks made frequent errors copying its. We can define the Planetary hours > as we like, but in the Renaissance, I have not doubt about his meaning: the > Planetary hours was used like the Unequal hours with add of the "planetary > Table" in the quadrantal instruments and in the sundials on the walls. > Egnatio Danti, Stoefler, Gallucci and others written about this saying that > the Planetary hours are the Unequal hours with the table of Planet influence. > I not would say that Drecker done a mistake. Maybe him say tha same thing > that I say. I believe that the ancient diallists done the unequal hours like > Drecker say, but this not meaning that the Planetary Hours are another > things. I remark that the Planetary hours are only a Table of influence of > Planets on the human body in each unequal hours. > In the file attached is a little bit of an interesting article of Mara > Miniati published in the Nuncius Magazine of the Museum of the History of > Science in Florence, about a beautifull quadrantal instrument of Wolckmer > from Brunswick (1600) in which read about the construction of the unequal > hour by Stoefler. > The best greetings > Nicola > > > > ---------- Initial Header ----------- > > From : [EMAIL PROTECTED] > To : "sundial" [EMAIL PROTECTED] > Cc : > Date : Wed, 16 May 2007 17:33:27 +0200 > Subject : Re: Re:Greek and Roman sundials > > > > > > > > > Nicola, > > > > You are right as you say that in literature usualy the planetory hours are > > equal to seasonal hours. > > Nevertheless the definition by Drecker (and Sacrobosco) is worth to look at. > > And it can be used as a timesystem. > > If it is a practical system or it is just forgotten is another discussion. > > > > Drecker certainly doesn't mean the ascendants and descendants, nor the > > astrological houses. > > He writes about these in separate chapters in his book and all with > > necessary figures. > > > > So I don't think Drecker made any mistake. > > > > Because this timesytem interested me years ago I incorpurated them in > > ZW2000. > > The output is just as in a figure by Drecker. > > > > Best wishes, Fer. > > > > > > Fer J. de Vries > > > > De Zonnewijzerkring > > http://www.de-zonnewijzerkring.nl > > > > Molens > > http://www.collsemolen.dse.nl > > > > Eindhoven, Netherlands > > lat. 51:30 N long. 5:30 E > > > > ----- Original Message ----- > > From: <[EMAIL PROTECTED]> > > To: "ferdevries" <[EMAIL PROTECTED]> > > Cc: "noamk1" <[EMAIL PROTECTED]>; "sundial" <[EMAIL PROTECTED]> > > Sent: Wednesday, May 16, 2007 4:55 PM > > Subject: Re: Re:Greek and Roman sundials > > > > > > > Dear Fer and Noam, > > > > > > I doubt of Drecker. I am sorry for my incapacity to write in correct > > > english as it is not easy for me write about this in english. In any case, > > > you write: > > > "Drecker defines the planetary hours in his book as the rise of 15 degrees > > > on the ecliptica. He makes a note in his book to a definition by > > > Sacrobosco (around 1230)." > > > > > > Ok, I think that Drecker have done a mistake. The hours of Drecker > > > definition I believe to be the "Ascendant and Discendant zodiacals signs" > > > and the Celestial Houses, but the Planetary House in the Renaissance are > > > the same that the Seasonal hours, but udes only for the influence of > > > planetes in each hours. In the astrolabes the unequal hours was used like > > > in the ancient time. Some time the astrologers and astronomery and > > > diallista used the name "planetary" hours to point out the "seasonal > > > hours" in the sundials. But in reality the Planetary hours are the ancient > > > unequal hours used for read the astral influence of planets about the > > > human body. > > > The best greetings, Nicola > > > > > > > > > > > > ---------- Initial Header ----------- > > > > > >>From : "fer de vries" [EMAIL PROTECTED] > > > To : "Severino, Nicola" [EMAIL PROTECTED],"noamk1" > > > [EMAIL PROTECTED] > > > Cc : "sundial" [EMAIL PROTECTED] > > > Date : Wed, 16 May 2007 10:03:41 +0200 > > > Subject : Re: Re:Greek and Roman sundials > > > > > > > > > > > > > > > > > > > > > > > >> Nicola, > > >> > > >> In this discussion you write: > > >> > > >> "The Planetary hours are equal to the seasonal hours ......" > > >> > > >> > > >> In most of the literature this is true but according to Joseph Drecker > > >> (1925) the planetary hours are different from seasonal hours. > > >> > > >> Drecker defines the planetary hours in his book as the rise of 15 degrees > > >> on > > >> the ecliptica. > > >> He makes a note in his book to a definition by Sacrobosco (around 1230). > > >> > > >> There are 12 hours in the day and in the night but because a sign rises > > >> fast > > >> or slow the lenght of each hour is different in the same day too. > > >> > > >> With my program ZW2000 these planetary hours can be calculted. > > >> They look strange and are not so easy to use in practice and rather > > >> difficult to construct. > > >> Calculation today with computer is easy. > > >> > > >> So far as I know this timesytem isn't seen on any real sundial. > > >> > > >> Best wishes, Fer. > > >> > > >> > > >> Fer J. de Vries > > >> > > >> De Zonnewijzerkring > > >> http://www.de-zonnewijzerkring.nl > > >> > > >> Molens > > >> http://www.collsemolen.dse.nl > > >> > > >> Eindhoven, Netherlands > > >> lat. 51:30 N long. 5:30 E > > >> > > >> ----- Original Message ----- > > >> From: <[EMAIL PROTECTED]> > > >> To: "noamk1" <[EMAIL PROTECTED]> > > >> Cc: "sundial" <[EMAIL PROTECTED]> > > >> Sent: Wednesday, May 16, 2007 9:24 AM > > >> Subject: Re:Greek and Roman sundials > > >> > > >> > > >> > You wrote: > > >> > > > >> > "This is why there is a difference between seasonal and planetary > > >> > hours...". > > >> > > > >> > Where is the difference between seasonal and planetary hours? > > >> > The Planetary hours are egual to the seasonal hours and are differently > > >> > only for a philosophical and astrological concepts. All treatises of > > >> > gnomonica on XVI-XVI-XVIIth century described the Planetary hours only > > >> > for > > >> > the astrological concepts. For this you can see Clavius, Vimercato, > > >> > Kircher, etc. > > >> > Nicola > > >> > > > >> > > > >> > > > >> > > > >> > ---------- Initial Header ----------- > > >> > > > >> >>From : [EMAIL PROTECTED] > > >> > To : [EMAIL PROTECTED] > > >> > Cc : > > >> > Date : Tue, 15 May 2007 22:37:10 +0300 > > >> > Subject : Greek and Roman sundials > > >> > > > >> > > > >> > > > >> > > > >> > > > >> > > > >> > > > >> >> I think my question may not have been clear. What I am interested in > > >> >> finding out is > > >> >> 1) Greek and roman sundials break up the day into 12 equal parts but > > >> >> the > > >> >> amount of time that will pass between each part will not be equal as > > >> >> the > > >> >> first and last hour will be longer by approximately 5 minutes due to > > >> >> refraction. This is why there is a difference between seasonal and > > >> >> planetary hours > > >> >> 2) If a Greek or Roman sundial was set up correctly according to what > > >> >> they thought was correct, would it actually tell seasonal hours > > >> >> accurately or not? > > >> >> The part that makes me wonder is the angle of the gnomon. > > >> >> > > >> >> 3) Is there any formula to calculate what would be the seasonal time > > >> >> on a > > >> >> Greek sundial that was accurately set up? > > >> >> > > >> >> Fred Sawyer gives the formula for the unequal hours > > >> >> http://www.sundials.org/publications/dcomp/dcomp2.htm > > >> >> > > >> >> > > >> >> Thanks again, > > >> >> Noam Kaplan > > >> >> > > >> >> > > >> >> ----- Original Message ----- > > >> >> From: Noam Kaplan > > >> >> To: [EMAIL PROTECTED] > > >> >> Sent: Tuesday, May 15, 2007 2:25 PM > > >> >> Subject: Greek and Roman sundials > > >> >> > > >> >> > > >> >> Does anyone know if the Greek and Roman sundials would in actuality > > >> >> show > > >> >> what they are theoretically supposed to show in term of the unequal > > >> >> hours? The gnomon was either horizontal or vertical, not on an angle. > > >> >> > > >> >> > > >> >> Thanks, > > >> >> Noam Kaplan > > >> >> > > >> > > > >> > > > >> > ------------------------------------------------------ > > >> > Leggi GRATIS le tue mail con il telefonino i-modeT di Wind > > >> > http://i-mode.wind.it/ > > >> > > > >> > > > >> > > > >> > --------------------------------------------------- > > >> > https://lists.uni-koeln.de/mailman/listinfo/sundial > > >> > > > >> > > >> > > > > > > > > > ------------------------------------------------------ > > > Leggi GRATIS le tue mail con il telefonino i-modeT di Wind > > > http://i-mode.wind.it/ > > > > > > > > > > --------------------------------------------------- > > https://lists.uni-koeln.de/mailman/listinfo/sundial > > > > > > > ------------------------------------------------------ > Passa a Infostrada. ADSL e Telefono senza limiti e senza canone Telecom > http://click.libero.it/infostrada > >
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