I wrote: Hi Franco-- >
Sorry to mis-write your name--I meant Francesco. 48 W November 20th 1649 UTC Michael Ossipoff On Wed, Nov 20, 2019 at 11:29 AM Michael Ossipoff <email9648...@gmail.com> wrote: > My dials will show 9 declination-lines: > > 1; Equinoxes, solstices, and half-solstice declinations > > 2. Declinations at the ecliptic-longitudes that divide each > astronomical-quarter (interval between an equinox and a solstice) into > thirds. > > So the dials will indicate solar-declination and solar-ecliptic-longitude > (expressed in thirds of an astronomical-quarter--the tropical signs of the > Zodiac, labeled with their traditional astrological symbols for the signs > of the Zodiac). > > The dials will also show Babylonian hours in the morning, and co-Italian > hours in the afternoon. > > The Cylindrical-Equatorial shows h and dec in a clear rectangular format, > and doesn't need explanation. > > The Horizontal Dial or course is the most easily-built stationary dial, > and is particularly-easily read from any direction by someone who is near > to it, and tells time whenever the Sun is above the horizon (except if it's > shaded at some times of day). > > A Cylindrical-Equatorial Dial can be built to tell time whenever the Sun > is above the horizon. The upper edge of the cylinder is trimmed horizontal, > and the nodus is a bead at the middle of a string transversely across the > cylinder, with the nodus-bead positioned on the cylinder's axis normal to > the dial's equator-line. The nodus-bead is also level with the > horizontally-trimmed top-edge of the cylinder. > > This Cylindricald-Equatorial is similar to the ancient Hemicycleum. > ...differing from it by using a cylindrical surface instead of a spherical > surface; using a string-mounted nodus-bead instead of a stick-gnomon (which > I consider to be an eye-injury-hazard); and not being cut-away as the > Hemicyclea usually were. > > 48 M > November 20th > 1628 UTC > Michael Ossipoff > > > > On Wed, Nov 20, 2019 at 11:00 AM Michael Ossipoff <email9648...@gmail.com> > wrote: > >> Hi Franco-- >> . >> I like explanations that can be understood by anyone from at least >> pre-secondary-school. I believe that such people can understand the sundial >> and map-projection explanations that I'd use. >> . >> To whom would I give explanations?: Primarily to my girlfriend. She >> isn't interested in math, but that doeesn't mean that those explanations >> wouldn't be understandable to her if she's interested in them, interested >> in lisening to them. >> . >> I mentioned to her that our windowsill sundial would be a >> Cylindrical-Equatorial Dial, because it doesn't need any explanation, >> because it shows the Sun's position in the most direct way. She replied >> that she has nothing against explanation of the Horizontal-Dial, its >> hour-lines and declination-lines, and considers it interesting. >> . >> So the first windowsill dial here will be a Cylindrical-Equatorial Dial, >> followed by a Horizontal Dial. >> . >> In general, I believe that these subjects can be explained to anyone who >> is interested in hearing the explanation. >> . >> So I'd offer these explanations to anyone to whom I'd suggest or offer a >> sundial or map-projection. I like the idea of a sundial or displayed map >> being accompanied by a pamphlet or a page that tells its >> construction-formula derivation-explanation. >> . >> Some say that people aren't interested in explanations, but I suggest >> that, rather, they're often just resigned to things being not explainable >> to them. I believe that, when shown a sundial or map, they'd like it >> explained. >> . >> It seems to me that every park, library, museum, plaza, and other >> public-spaces, should have a sundial. >> . >> >> ------------------ >> >> I'm not familiar with those softare products, but I'd have no objecion to >> their use. I'd use drawings, but of course that software could be helpful >> too, showing things in ways other than what a drawing can show. >> >> 48 W >> November 20th >> 1600 UTC >> . >> Michael Ossipoff >> >
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