Copy letter from Herbert Rix, to Sociedad "Antonio Alzate" Observatorio Meteorologico Central de Mexico 'Sir, I have the pleasure to inform you that your application for exchange has been considered, & that 'The Proceedings of the Royal Society' will in future be posted to you in exchange for your Mémoires. I am yours faithfully, Herbert Rix Asst Sec RS [Assistant Secretary, Royal Society]'. 25 July 1888