Mac Oglesby wrote: > >You don't mention the size (height and diameter) of the pole. If you >can use the tip of the pole, or conveniently place an indicator >(nodus), you can easily construct a "normal" horizontal dial, or >perhaps an "hours until sunset" dial. Either of these dials only need >straight lines, and can be designed using readily available software. >Check the NASS website under Links. > Home at last from the stimulating NASS/Banff Conference and the following week enjoying the kind hospitality of Roger & Christine Bailey I've now erased the 500+ bits of accumulated email spam and can begin to re-focus after a 12 hour sleep.
Having twice had my luggage forced open with expensive damage to case and contents (both ways) by US Security while passing through Minneapolis in transit I would advise never travelling with a metal object either as cabin baggage (outward) "You might use it to attack the crew Sir!" or as hold baggage (return) when they cut an expensive security strap and forced the catches on my sturdy Samsonite suitcase and ....."the TSA is not liable for damage to your locks resulting from this necessary safety precaution" I've yet to see if the resulting damage to the heliochronometer dial plate can be claimed for although I doubt it. A lethal sundial! Now there's a new concept. While still learning my craft some years ago the idea of using the tip of a vertical pole as a 'nodus' confused me at first so I think some additional explanation for beginners in the light of my own ignorance might be useful. Of course I finally realised that it is just part of of the imaginary style edge of the gnomon of a conventional horizontal dial. Locate the origin of the horizontal dial by drawing an imaginary line, sloped at the local latitude, and co-planer with the north/south meridian, through the nodus and the hourlines radiating from that point on the ground can be plotted. As a teacher I was often accused of 'spoon feeding' my pupils. Old habits die hard I suppose. Tony Moss. -
