Correspondence with Reginald L. Waterfield regarding problems relating to the measurements of photographic plates featuring comets and concerning the calculations connected to this; refraction corrections for stellar positions and the reduction of their coordinates as measured from photographic plates; the International Astronomical Union meeting at Brighton in July 1970 and Waterfield's desire to meet Brian Marsden and Elizabeth Roemer there; the fact that in November 1970 plates of Comet Encke had been taken two weeks before and that in January 1971 this comet was 'low down in the sunset'; various unnamed comets; the more practical aspects of astrophotography; and the methods employed by Eratosthenes and Herodotus.