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]


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