Have you read "Calendrical Calculations"? http://www.cup.cam.ac.uk/catalogue/catalogue.asp?isbn=0521777526 Tony. -- f.a.n.finch <dot at dotat.at> http://dotat.at/ BISCAY: WEST 5 OR 6 BECOMING VARIABLE 3 OR 4. SHOWERS AT FIRST. MODERATE OR GOOD.