Hello Alessandro,
I appreciate your chronology below, thank you. Also, I appreciate your
idea of colorizing the Analemma to improve its readability. The output
of my Sundial Generator (see URL below) does exactly this, i.e., the
Analemma is divided into four segments (colors) each of which
corresponds to a season the EoT correction is to be used in. I know
first hand that this helps.
http://www.gcstudio.com/makedial.html
Best,
Luke Coletti
gunella wrote:
>
> Regards to you all
>
> Many thanks for the "Amateur scientist" article.
> And now I like sameone explains to me where is the novelty in that dial.
> A) the vertical gnomon is in use from although 2000 years (See Plinius : the
> dial with obeliscus, in Rome -Campo di Marte, built up to honour Caesar
> Augustus). The polar gnomon has about 500 Years.
> B) I think the first analemma (in French "ligne des heures moyennes", in
> Italian "Lemniscata") was drawn by Grand-Jean de Fouchy - about 1735- (See M.
> Deparcieux - Nouveaux Traités de Trigonometrie etc.. - Paris 1741- Pag. 94 of
> Traité de Gnomonique).
> A piece of advice to the diallists vho draw the first time a "Sloan" dial.
> Draw the two branchs of the ANALEMMAS in red and blue; the readability of the
> dial improves.
>
> Alessandro Gunella 45N 8E - [EMAIL PROTECTED]
