To John Harding's question concerning the sign of the equation of time there is, for navigators of ships at least, a simple answer. Any instructional book on nautical astronomy will say that the equation of time is defined as mean time minus apparent time, i.e. clock time minus sun time. So on days when the sun transits the meridian before noon (local mean time) the sign is negative. By the way, astro-navigators are an endangered species in these days of satellites. We should treasure them, for they are the only creatures apart from us dialists who believe the sun goes round the earth each day.
Frank Evans (former ship's navigator)
