A convenient beginning for a survey of London and astronomy seems to be with Geoffrey Chaucer, who was not only the outstanding English writer of the middle ages, but was closely linked with London and was an accomplished astronomer.
In his last annual report the Astronomer Royal stated that ""It is clear that the final value of tho solar parallax derived from the observations of Eros in 1931 will be nearer 8"".79 than 8"".80"". This means that the Sun's distance is nearer 93,000,000 miles than 92,900,000 miles, the latter being the distance used at present for all computations.
From the earliest days, time has boon connected with sunrise and sunset. Midway between sunrise and sunset the, sun bears neither east nor west, that is, it is on the meridian. This is a well-defined instant and, as soon as pointers had been set up in the meridian, was used by astronomers to mark the commencement of a solar day.