Mario Arnaldi misspelt David Young's name. I am a member and have a complete list of members, some of whom, including Fred Sawyer, are in the USA. I will look it up later today to see if any are in California. Back issues of the Bulletin are available. I don't have them all, but don't remember seeing any articles on calculating ceiling dials.
BTW, on the subject of ceiling dials, I have invented a type which needs just one short scale by virtue of using several mirrors to 'fold' the optical path. I am working on an article for submission to the BSS Bulletin. If anyone is interested, please email me at [EMAIL PROTECTED] Regards Chris
