Article View: sci.misc
Article #206Sundial Summary
From: ronald.w.doerfler
Date: Sat, 21 Nov 1992 23:59
Date: Sat, 21 Nov 1992 23:59
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8519 bytes
I am posting this sundial article because I cannot get through on e-mail to Alan Paeth, who was interested in any response to my request for sundial magazine or organization information. Well, I've had no luck so far in my quest for any organizations or magazines for sundials. A couple of people have indicated their interest in sundials, but didn't have any leads. Since I see the term "dialists" in books and articles, I assumed that a fair group of people had an interest in this niche field, much like my other interest of stereo photography (there are magazines and organizations for this!). I haven't found anything yet. I have rounded up some articles and books myself, so I am listing a short bibliography of the better ones (they are in no particular order): SKY AND TELESCOPE magazine: July, 1972: "The Shape of the Analemma" by Bernard Oliver, pp. 20-22. An excellent article of the origins of the curve. June, 1960: "A New Universal Sundial Design" by Hermann Egger, pp. 470-471. Wavy hour lines take care of Equation of Time (Analemma) Correction. July, 1953: "About Sundials" by H. Egger, pp. ? Nice pictures. December, 1975: "A Design for an Analematic Standard-Time Sundial" by P. Kenneth Seidelmann, pp. 368-369. Large walk-about analemmatic sundials--people move a gnomon to correct location for the day of the year. January, 1982: "A Bit of Porcelain" by R. Newton Mayall, pp 16-17. Describes a nice-looking old sundial. July, 1982: "Gleanings for ATM's", monthly column, pp. 86-88. Describes a neat sundial full of analemmas. November, 1982: (same column as above?) pp. 486-487. Describes a sundial with an analemmatic-shaped gnomon. December, 1987: Astronomical Computing monthly column, pp. 646-648. Describes sundials on walls. July, 1964: "Making Portable Sundials" by R. Newton Mayall, pp. 9-12. Graphical instructions. November, 1966: "Results of Sundial Competition" by Hermann Egger, pp. 256-?. A few neat ones. October, 1968: "Sundial at Riverside" by Imre Kalincsak, pp. ??. Discusses one sundial. November, 1972: "A Hybrid Sundial" by Albert Ericson, p 299. Discusses one sundial. Amateur Scientist Column of Scientific American: December, 1980, p. 230. A neat "analemmic" sundial. May, 1966, pp. 128-136. Instructions for making a card dial. September, 1953, p. 160. Various Dials. October, 1954, p. ?. Sundials of some sort. The Amateur Scientist, Simon and Schuster, NY, 1960. (full name: The Scientific American Book of Projects for the Amateur Scientist): Chapter 8: "A Sundial that Keeps Clock Time" Curved gnomon to account for Analemma. Chapter 7: "A Universal Sundial" Very interesting chapter on using an aligned globe to calculate the time, declination, sunrise and sunset, etc. "The Astronomer's Odd Figure 8" by Kenneth L. Franklin, Natural History, October, 1962, pp. 8-15. Great graphics. Sundials: Their Theory and Construction, by Albert E. Waugh, Dover, NY, 1973. ABSOLUTELY the best book on sundials and instructions on calculating and making them. Available still in bookstores (and libraries). Sun-dials and Roses of Yesterday, by Alice Morse Earle, Charles Tuttle Publishing Co., 1971 (second printing 1984). Originally published in 1902, this is a curious book full of the history and romance of sundials-- not for everyone, though there are many, many pictures of sundials, albeit poor quality black-and-white ones per the era. Sundials, by Christopher St. J. H. Daniel, Shire Publications Album 176, England, 1986 (reprinted 1990). A 32-page booklet on various sundials. Sundials on Walls, by above author, Maritime Monographs and Reports No. 28- 1978, National Maritime Museum, Greenwich, London SE10 9NF. A 25-page booklet describing various existing wall dials. In addition, R, Newton Mayall has a book on sundials that I concluded was inferior to Albert Waugh's book above. Portions of Mayall's book were printed in a series of old Scientific American articles sometime earlier this century. I received an e-mail note from a Bruce Gold in Utah that wondered if my interest in sundials was the same as his: the fact that a skimpy, surface knowledge of the field is insufficient, unlike many fields of interest. You have to have knowledge and a feel for orbital mechanics of the earth. I am reproducing my reply here: >Hi Bruce, > > You know, you're probably right about the reason for my >interest in sundials. My educational background is in physics and >mathematics and I'm sure that the mathematics required and the >orbital mechanics involved is the most interesting part. I also >like the ingenious designs people have come up with, and I'm >pleased to learn that a well-made, location-specific sundial with >due regard to the correction for the Equation of Time can actually >be highly accurate. I tell people that in the long run they are >more accurate by definition because atomic clocks and other official >timekeepers are adjusted occasionally with leap seconds to keep our >time in line with sun time. > > By the way, my understanding is that sundials are MUCH >simpler to accurately make than lunar dials. A sundial can be >used during the night when lit by the moon by subtracting something >like 48 minutes a night from the reading for each night since the last >new moon (when the moon lined up with the sun). > > I first became interested in sundials when I was on a beach >a couple of years ago on a small island in Lake Michigan. A kid >asked his dad if it was time to go to catch a boat back to the >mainland. The dad took a stick, stuck it upright in the ground in the >middle of a cross he drew in the sand, and looked at the shadow, >declaring the time. This was extremely curious to me, and I >started to look into these things. I was eventually shown to >be correct in my original gut feeling that what the dad did was >total nonsense. > > I look for sundials now when I go places and I like to check >them out. I usually find them appallingly misunderstood. I have found >them pointing other directions than North, I have seen equatorial dials >lying flat on their gimbals rather than tilted (at one place the staff >returned the dial to the horizontal position within 5 minutes of my >correcting it), and I see the types often sold in stores. Many of >these are off by hours and yet no one cares enough to find the reason-- >no wonder the average person thinks sundials are so inaccurate (in >addition to the latitude and longitude dependencies in sundials). > > There is a Time Museum in Rockford where I lived that has >many authentic old sundials and clocks (the latter of which don't >seem near as interesting). Speaking of orbital knowledge, I bought >a kit there produced by the National Maritime Museum in Greenwich, >England and assembled an astrolabe. This is really neat, and I've >used it to sight on the sun and align the star map (on the rete) for >the date to find the apparent time of day, which I correct for standard >clock time. I intend to sight on particular stars with it too >whenever the November clouds and rain end around here. Columbus >had one on his 1492 voyage and consistently misread it because of his >confusion with the tropical southern sky. > > I'm settling on a design for a wall sundial for the outside of >my house. The house lies along the NW to SE line, so the calculations >involved make it interesting. Albert Waugh's book, Sundials: Their >Theory and Construction, is the absolute best book I've found on calculating >various types of sundials such as this. It's available in bookstores. > > Well, it's been nice monologue-ing. Maybe you could let me >know what sort of interesting sundial things you've run across. > > > Ron Doerfler > Naperville, Illinois > /Ron Doerfler
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Newsgroups: sci.misc Path: arc1-ca.pugleaf.net!sparky!uunet!spool.mu.edu!uwm.edu!linac!att!cbnewsk!cbnewsj!att-out!cbfsb!cbnewsf.cb.att.com!doerfler From: doerfler@cbnewsf.cb.att.com (ronald.w.doerfler) Subject: Sundial Summary Message-ID: <1992Nov21.235919.7804@cbfsb.cb.att.com> Keywords: sundials Sender: news@cbfsb.cb.att.com Organization: AT&T Distribution: na Date: Sat, 21 Nov 1992 23:59:19 GMT Lines: 197