Berton Willard, _ Russell W. Porter_, pub. 1976, does have several pages on dials. His Garden Telescope can be used as a sundial. There is a picture on p203 of a dial with a wire gnomon running between the tail and head of a sculpted dolphin. Adjustment for equation of time was provided, and the entire unit was mounted in a spherical bowl, allowing adjustment for latitude. He experimented with using lenses & prisms to project an image of the sun onto the hour circle. The image of the sun was aligned with crosshairs, simultaneously viewing the hour circle. Another dial used lenses & prisms to project onto ground glass both the sun's image and part of the hour circle (if I'm reading this correctly, p.205). Pictured on p204 is a beautiful dial made inside a glass sphere. The hour circle is attached outside the glass, the analemma inside, and the sphere is rotated until a lens cast the sun's image onto the equation of time. He also made sunclocks, where the dial is turned to cast a shadow onto the analemma, and via gears, clock hands indicate the time. There is a photo of one on p206. The most accurate of these could tell time to within seconds. Porter made at least 19 sundials and sunclocks. The Aug. 1928 and Aug. 1935 Scientific American had an article by RP on sundials. The above information seems to have been written without seeing the actual dials, so any mistakes are from that removal, and my own transcribing. This is a fairly common book, it should be easy to find in libraries. \\\\\\\\\\\\\\\\\\\\//////////////////// Peter Abrahams [EMAIL PROTECTED] the history of the telescope, the microscope, and the prism binocular
