Hello All

I've made measurements, drawings and a working model of my proposed sundial
adaptation of the McMath-Pierce Solar Telescope at Kitt Peak, Arizona and am
submitting a proposal to Kitt Peak officials soon.  I'll also be giving a
short talk on this giant sundial at the NASS conference.

Early on in the dial face design, I realized that this very thick gnomon has
four possible styles because it is in the shape of a square box, each corner
being a different style that functions at different times of the day. I
noticed that as the sun moves around the gnomon, the leading edge of the
shadow is produced by different styles and that there is an instantaneous
moment of transition when the style shifts to the next style.  The only
thing an astute observer sees on the ground at this moment is that the "fuzz
zone" of the shadow will change a little in width, otherwise the shadow's
movement is a smooth, continuous motion. This is great, because it means
that on the face, the hour numbers will appear in consecutive numerical
order just like on an ordinary sundial. (The spacing between the hour points
gets a little strange during the style shift, however). It will be very
user-friendly.

But its design is more difficult.  I found that none of these styles work
all day, because they are all shaded at sometime during the day by the
structure.  So to make a sundial with hour points from sunrise to sunset, I
have to use multiple styles.  It takes at least three styles to cover the
entire span of daylight hours.  (I use the bottom, east and top styles in my
design).

Has anybody ever heard of a one-faced sundial with multple wrap-around
styles? For example, instead of a four-sided gnomon, how about a three or
fived-sided gnomon (You can exclude the common two-sided thick gnomon and
the analemma shaped gnomon).

p.s. If anybody would like me to send a PDF of my drawing, let me know...

John

John L. Carmichael Jr.
Sundial Sculptures
925 E. Foothills Dr.
Tucson Arizona 85718
USA

Tel: 520-696-1709
Email: [EMAIL PROTECTED]
Website: <http://www.sundialsculptures.com>

-

Reply via email to