Hi Frank, Yes, in fact the ellipse for my front yard analemmatic dial was constructed using pegs and rope. It did not turn out half bad, but I know what you mean.
Now that you have pointed it out to me, the string proof is obvious... :) Thank you. Rudolf -----Oorspronkelijk bericht----- Van: Frank King [mailto:f...@cl.cam.ac.uk] Onderwerp: Re: Sundial Puzzle Corner Dear Rudolph, Glad you enjoyed the puzzle or, at least, the solution... > Brilliant! You add... > I never realized that the distance from the focus to the end of the > minor axis equals the half major axis... Have you never tried drawing an ellipse with a Length of String and Two Pins? This is illustrated all over the web, for example here: [proof] --------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial
