Big enough of course to fit every dialist that deserved it; but what I mean is this:
>1. Is there any flat surface anywhere that never gets sunshine at some >moment during the year? If you mean direct sunlight, yes, lots of them. Trivially, any point adjacent to, and away from the equator from, a vertical wall, convex-polygonal or elliptical/circular in plan, the ends of which cast shadows on it even at summer sunrise and sunset. Tof produce a minimum single point, the arc traced by such a wall would not have to be great, although it increases with latitude. Extending that, there must be a zone of perennial shade -- you guys with computers can calculate the general formula for its shape and extent based on the latitude and the height of the wall -- including points not immediately adjacent to the wall. Practically speaking, this is the principle behind the urban layout of many old Mediterranean towns: narrow streets make for constant shade in the summer; if in addition they are not straight, they also temper winter conditions. I noticed this in several towns of central Italy; one of which -- Pitigliano, in Tuscany -- has a sundial in about the only place it can have one near ground level: in a piazza where the streets widen out. Geographically, there must be plenty of deep non-N-S valleys, and surely steep enough mountains act as my walls, above, for places on their "leeward" side so to speak. The question then becomes: "Where is the *largest* such surface on Earth? (Now there's a project...!) A similar question would be "Where is the largest *volume* of air on Earth never to see direct sunlight?" *** BTW, did anyone see the special on Noah's Ark last night? in which God's rainbow was shown with the colors backward... A miracle indeed! Bill Thayer LacusCurtius http://www.ukans.edu/history/index/europe/ancient_rome/E/Roman
