Noam Kaplan queried: > >2) Also, why does Waugh write that the sun will never shine on a vertical >direct south dial before 6 AM or after 6 PM? If sunrise is at 5 AM >wouldn't a shadow be cast on a vertical direct south dial? > What you need is a copy of Mike Shaw's 'Universal Dialist's Companion'. This simple device is settable for any latitude and solves all such mysteries in graphical terms that are easy to see and understand. My own copy is always to hand to get me out of conceptual knots.
Your puzzlement may arise from the mis-concept that the sun always rises due east when if fact during the summer it rises and sets well north of east/west. My UDC tells me that on midsummer day the sun rises at my latitude - 55° north - at just after 3.0am (GMT) and at a point on the horizon approx. 45° north of due east. Before/after 6.0 am/pm it is shining on the north face of an east/west wall. You can contact Mike, with whom I have no business etc. association, for more info' perhaps at < [EMAIL PROTECTED] > Tony Moss -
